F200 + F201: AAQ IT Data Analytics Revision Notes

OCR H019/H119     F200 exam 1 hour 15 minutes, 60 marks     F201 exam 1 hour 30 minutes, 60 marks

Topic 1 - Understanding data

1.1  Data, information and knowledge

Data
Raw facts and figures with no context or meaning on their own, for example 40, Small, £9.00. This is the exact wording OCR's sample paper rewards.
Information
Data that has been processed, organised and given context so it has meaning, for example "40 small pizzas were sold on Saturday".
Knowledge
Understanding gained by interpreting information, using experience, to draw conclusions and make decisions, for example "Saturday is the best day for sales, so add staff on Saturdays".

Sources: data comes from transactions, sensors, forms and questionnaires, websites, social media, records and documents. Information comes from processing that data in reports, databases, spreadsheets and dashboards. Knowledge comes from people (experience, expertise) and from analysis of information.

How they interact: data is the input; processing (sorting, calculating, grouping, comparing) gives it context and turns it into information; interpreting information, together with experience, gives knowledge. Knowledge then decides what new data to collect, so the three form a cycle. The difference is the amount of meaning: data has none on its own, information has context, knowledge supports a decision.

How data is converted to information: collect it, check and clean it, organise it (sort, group, put into tables), process it (calculate totals, averages, comparisons), then present it with labels and context.

Benefits to organisations and individuals
Better, evidence-based decisions. Trends spotted and future demand predicted. Targeted marketing and personalised services. Efficiency: right stock, right staffing levels. Individuals get tailored recommendations, quicker services and access to public information.
Limitations
Poor-quality data leads to wrong decisions. Collecting, storing and securing data costs money and staff time. Legal duties under the DPA 2018 and UK GDPR. Risk of breaches and misuse. Too much data can overwhelm people (information overload). Individuals lose privacy.
Positive impacts on society
Healthcare planning and disease tracking, public transport and traffic planning, crime prevention, education planning, and open government data that lets the public hold organisations to account.
Negative consequences for society
Loss of privacy and surveillance, identity theft after breaches, bias and discrimination when decisions are based on unrepresentative data, spread of misinformation, and a digital divide between people who can and cannot access data-driven services.

OCR's sample mark scheme rejects answers that repeat a column heading with no context. "Prices" is not an item of information; "the price of a large pizza is £14.00" is. For knowledge, give a conclusion such as "large is the most popular size", not another fact.

1.2  Big data

Big data is data sets so large, fast-growing and varied that traditional software (a single spreadsheet or desktop database) cannot capture, store and process them in a reasonable time. It is usually described by its characteristics, such as volume, velocity and variety (F201 covers all six Vs).

Sources
Social media posts, online transactions and loyalty cards, website clicks and searches, sensors and IoT devices, GPS from phones and vehicles, CCTV and images, medical records, scientific instruments.
Formats and structure
A mix of structured data (tables, transactions), semi-structured data (JSON, XML, emails) and unstructured data (text, images, video, audio). Most big data is unstructured.
Applications
Recommendations in online shopping and streaming, fraud detection in banking, predicting demand in retail, route planning, weather forecasting, healthcare research, targeted advertising.
Benefits
Patterns and trends found across very large samples, so predictions are more reliable. Personalised offers to customers. Staffing and stock matched to demand. Faster detection of fraud or faults. New products and services identified.
Limitations
Needs expensive storage, processing power and specialist staff. Quality and accuracy are hard to guarantee. Privacy and legal risks when personal data is involved. Security risk: a large breach affects many people. Results can mislead if the data is biased.

Not in F200: the evolution of big data, data preparation techniques, data mining techniques and big data infrastructure. These are F201 content.

In "explain two benefits of big data" questions, OCR gives one mark for the benefit and one for applying it to the organisation, for example "analyse past sales data across the chain (1) so each restaurant has the right number of staff at each time of year (1)". Answers not related to the scenario get no marks.

1.3  Data and file formats

A data format is the structure in which data is stored or encoded in a file, so that software knows how to read it. (OCR's sample paper asks "What is data format?" and the answer is structure.)

ASCII
Character set where each character is a number; standard ASCII uses 7 bits (128 characters), extended ASCII 8 bits (256) Where it is used: Plain text files, simple data exchange, program code. Benefits: Small files; read by almost any system. Limitations: English letters and symbols only; no other alphabets or emoji (Unicode is needed for those)
AIFF
Audio Interchange File Format; uncompressed audio, developed by Apple. Where it is used: Music production and editing, mainly on Apple devices. Benefits: Full CD quality, no quality lost. Limitations: Very large files; less widely supported than WAV or MP3.
WAV / WAVE
Waveform Audio File Format; usually uncompressed audio, developed by Microsoft and IBM. Where it is used: Recording, editing, sound effects, Windows systems. Benefits: High quality; widely supported. Limitations: Large files; slow to stream or share.
XML
Extensible Markup Language; text with user-defined tags, e.g. <price>9.00</price>; nested hierarchy. Where it is used: Exchanging data between systems, configuration files, SOAP and XML-RPC APIs. Benefits: Human and machine readable; self-describing; supports validation against a schema. Limitations: Verbose, so larger files and slower to process than JSON.
JPEG
Compressed image format for photographs; millions of colours. Where it is used: Photos on websites and social media, digital cameras. Benefits: Small files, fast to upload; supported everywhere; accurate colour. Limitations: Quality drops when compressed heavily; no transparency.
PNG
Image format that keeps full quality and supports transparency. Where it is used: Logos, icons, screenshots, web graphics. Benefits: Sharp edges and text; transparent backgrounds. Limitations: Larger than JPEG for photographs.
TIFF
High-quality image format, often uncompressed; can hold layers. Where it is used: Printing, publishing, scanning, archiving, medical images. Benefits: Very high quality; good for editing and print. Limitations: Very large files; not displayed by most web browsers.
JSON
JavaScript Object Notation; text made of key-value pairs, e.g. {"size": "Small", "price": 9.00}. Where it is used: Web APIs (REST, JSON-RPC), web and mobile apps, NoSQL databases. Benefits: Lightweight; easy for people and programs to read; fast to parse. Limitations: No comments; fewer built-in validation features than XML.
Numeric
Data stored as numbers (integers or real numbers) rather than as text. Where it is used: Measurements, prices, sensor readings, calculations. Benefits: Can be calculated, sorted and graphed directly. Limitations: Numbers stored as text cannot be calculated; leading zeros (e.g. phone numbers) are lost.
CSV
Comma-separated values; plain text, one record per line, fields separated by commas. Where it is used: Importing and exporting between spreadsheets and databases. Benefits: Small; opened by almost any spreadsheet or database. Limitations: No formatting, formulas or multiple sheets; a comma inside a field causes errors.
Fixed width
Plain text where every field takes a set number of characters, padded with spaces. Where it is used: Older and legacy systems, bank and government data files. Benefits: Fields are always in the same position, so easy to read by position. Limitations: Wasted space from padding; data longer than the width is cut off.
TXT
Plain, unformatted text. Where it is used: Notes, logs, simple data. Benefits: Tiny; opens on any device. Limitations: No formatting or structure; hard to analyse.

Not in F200: any format not listed above, and lossy and lossless compression.

OCR's mark scheme for "one benefit of JPEG for social media" credits: the file can be compressed so many images upload quickly; it is highly compatible so social media platforms accept it; it gives accurate colour. Each benefit needs an expansion linked to the context for the second mark.

1.4  Data types and classifications

Boolean
Only two values: True or False (Yes/No) Example use: In stock? Paid? Member? Benefits: Smallest storage; easy to filter and validate. Limitations: Cannot hold "unknown" or more than two options.
Character
A single letter, digit or symbol. Example use: Size code S, M, L; gender code. Benefits: Small storage; easy to validate. Limitations: Only one character.
Date
A calendar date (and/or time) stored in a date format. Example use: Date of birth, order date. Benefits: Can be sorted and used in calculations (days between dates) Limitations: Format differences (UK DD/MM/YYYY vs US MM/DD/YYYY) cause errors.
Integer
Whole numbers, positive or negative. Example use: Quantity sold, number of students. Benefits: Exact; fast to calculate; less storage than real. Limitations: No decimal parts.
Real
Numbers with a decimal (fractional) part. Example use: Price £9.99, temperature 21.5. Benefits: Accurate measurements and money. Limitations: More storage; can have small rounding errors.
String
A sequence of characters: letters, digits, symbols. Example use: Names, postcodes, phone numbers. Benefits: Holds any text, including numbers that are not calculated (phone numbers keep leading zeros) Limitations: Cannot be used in calculations; uses more storage; harder to validate.
Qualitative
Descriptive data about qualities, opinions and characteristics that are not measured with numbers, e.g. "the service was friendly". Gives depth and reasons, but is harder to analyse and compare.
Quantitative
Numerical data that can be counted or measured, e.g. 160 pizzas sold. Easy to analyse statistically and graph, but does not explain why.
Structured
Data stored in an organised, predefined format such as tables of rows and columns with set fields and data types, e.g. a holiday database of destinations, dates and prices. Easy to search, sort and analyse.
Unstructured
Data with no predefined model or organisation, e.g. emails' body text, social media posts, images, audio and video. Holds rich detail but needs more processing (often AI) to analyse.

"State two reasons why this data is structured" (sample paper): OCR credits "it is stored in an organised format" and "it is stored in tables, in columns and rows". Qualitative/quantitative is about what the data describes; structured/unstructured is about how it is organised. Keep the two pairs separate.

Topic 2 - Managing data

2.1.1  Data lifecycle management (DLM)

Data lifecycle management (DLM) is managing data through every stage of its life, from when it is created until it is destroyed. The five phases in order are:

1 Creation
Data is generated or captured: typed in, collected from forms, sensors or transactions, or imported from another source.
2 Storage
Data is saved securely in a suitable store (database, file server, cloud) with backups and access controls.
3 Usage
Data is processed, analysed, shared and presented to support decisions. Most access controls apply here.
4 Archival
Data no longer in active use but that must be kept (for legal, audit or historical reasons) is moved to cheaper long-term storage.
5 Destruction
Data that is no longer needed is securely and permanently destroyed so it cannot be recovered.

Interactions and iterations: the phases are not strictly one way. Data in use is updated and stored again; archived data can be retrieved back into usage (for an audit or a legal request); new data created from analysis restarts the cycle. Retention rules decide when data moves from usage to archival and from archival to destruction.

Benefits of DLM: data stays accurate and available when needed; storage costs fall because old data moves to cheaper storage; security improves because each phase has controls; it supports compliance with the DPA 2018 and UK GDPR (storage limitation: do not keep personal data longer than needed); and secure destruction reduces breach risk.

The sample paper asks you to put the five phases in order. Learn the order: Creation, Storage, Usage, Archival, Destruction. Marks need the correct order, not just the names.

2.1.2  Data analytics pipeline

The data analytics pipeline is the series of phases that moves raw data from its sources to the people who use the results. Each phase's output is the next phase's input.

Capture (data ingestion)
Collect data from sources such as databases, forms, sensors, APIs, files and social media; import it in batches or as a real-time stream. Purpose: Bring all the needed data into one place.
Process (data transformation)
Clean (remove duplicates, fix errors and missing values), validate, convert formats and data types, combine sources (data wrangling) Purpose: Make the data accurate, consistent and ready to analyse.
Data storage (data stores)
Save the prepared data in databases, data warehouses, data lakes or cloud storage, with security and backups. Purpose: Keep the data available and secure for analysis.
Analysis
Apply statistical methods, queries and analytics (descriptive, diagnostic, predictive, prescriptive, cognitive) to find trends and patterns. Purpose: Turn data into information and insight.
Use (visualisation)
Present results in dashboards, charts, reports and infographics; share with decision makers. Purpose: Communicate the findings so decisions can be made.

Iterations and interactions: analysis can show that data is missing or poor quality, sending the work back to capture or processing; feedback from users of a dashboard can change what is captured; new data keeps flowing in, so the pipeline runs continuously rather than once.

DLM describes the life of the data itself (creation to destruction). The pipeline describes how data is turned into insight (capture to use). Questions on job roles (Topic 5) expect you to say which phase each role works in.

2.2.1  Data assurance considerations

Data assurance means making sure data can be trusted. Each consideration below increases confidence in the data; failing on any one affects how it can be collected and used.

Accuracy
Data is correct and free from errors; it matches the real-world value. How it increases confidence / effect on collection and use: Decisions based on it are correct. Inaccurate data (wrong prices, addresses) causes wrong decisions and lost money.
Quality
Overall fitness for purpose: accurate, complete, consistent, relevant and up to date. How it increases confidence / effect on collection and use: High-quality data gives reliable analysis; poor quality means time spent cleaning and results that cannot be trusted.
Redundancy
The same data stored more than once. How it increases confidence / effect on collection and use: Unplanned duplication wastes storage and causes inconsistency (one copy updated, the other not), so it is reduced. Planned redundancy (backup copies) protects availability.
Reliability
Data comes from a trustworthy source and gives consistent results each time it is collected. How it increases confidence / effect on collection and use: Users can depend on it; unreliable sources (biased surveys, faulty sensors) make conclusions unsafe.
Timeliness
Data is up to date and available when it is needed. How it increases confidence / effect on collection and use: Out-of-date data leads to decisions about a situation that no longer exists, e.g. stock levels from last week.
Validation
An automatic check that data entered is reasonable and sensible and follows rules (range, type, length, format, presence, lookup) How it increases confidence / effect on collection and use: Stops impossible values being stored. It cannot prove data is correct: a valid age of 34 may still be wrong.
Validity
Data is in the correct format and within the allowed values for its purpose, and it measures what it is meant to measure. How it increases confidence / effect on collection and use: Invalid data cannot be processed or gives meaningless results.
Verification
A check that data has been copied or entered correctly from its source, e.g. double entry, visual check against the original, proofreading. How it increases confidence / effect on collection and use: Catches transcription errors that validation cannot, such as typing 43 for 34.

Validation checks data is sensible; verification checks it matches the source. Neither guarantees accuracy on its own, which is why both are used.

2.2.2  Data gathering

Data gathering is the process of collecting data from sources to answer a question or meet a requirement. The process: define the purpose and the data needed, choose a method and a sample, collect the data, check its quality (validate, verify, clean), then store it securely.

Documents and records
Data already exists, so it is cheap and quick; historical data available. Limitations: May be out of date, incomplete or collected for a different purpose.
Focus groups
Detailed opinions and discussion; ideas build on each other. Limitations: Small sample; dominant people sway the group; time-consuming to analyse.
Interviews
In-depth answers; can ask follow-up questions; can observe reactions. Limitations: Slow and costly; small sample; interviewer can bias answers.
Observations
Shows what people actually do, not what they say they do. Limitations: People change behaviour when watched; does not explain why; time-consuming.
Online tracking
Automatic, large volumes of real behaviour (clicks, pages, time on site) Limitations: Privacy concerns; needs consent for cookies under PECR; shows what, not why.
Questionnaires and surveys
Reach many people cheaply; easy to analyse closed questions. Limitations: Low response rates; badly worded or leading questions; dishonest answers.
Social media monitoring
Real-time public opinion about a brand or topic; huge volumes. Limitations: Unstructured and hard to analyse; not representative of all customers; fake accounts.
Transactional tracking
Accurate record of what was bought, when and where; captured automatically at the point of sale. Limitations: Shows purchases, not reasons; personal data must be protected.
Verbal histories
First-hand spoken accounts of experiences and events; rich detail. Limitations: Memory can be inaccurate; slow to record and transcribe; hard to compare.
Defining requirements
Be clear what question the data must answer and what the output will be used for, so the right data is gathered first time.
Defining relevant data
Collect only the data needed for the purpose. Irrelevant data wastes time and storage, and collecting unneeded personal data breaks data minimisation under UK GDPR.
Avoiding bias
Use a representative sample, neutral (not leading) questions and more than one source, so results reflect the whole population.

Meeting its purpose and good quality: check the data answers the requirement, comes from a reliable source, is accurate, complete, up to date and unbiased, and has been validated and verified.

Consequences of poor-quality data: wrong conclusions and poor decisions, wasted money and time, lost customers and reputation, and possible legal problems (inaccurate personal data breaks the accuracy principle).

For "explain two benefits of gathering data this way", use the scenario every time. OCR's model answer for street interviews: "many different people pass through the day (1) so the researcher gains a variety of opinions (1)". Generic answers are rejected.

2.3.1  Data states

Data in transit (motion)
Data moving across a network or between devices, e.g. an email being sent, a file uploading to the cloud, card details sent to a payment server. Protected with encryption in transit (HTTPS/TLS, VPNs).
Data at rest
Data stored and not currently being used or moved, e.g. files on a hard drive, a database on a server, backups and archives. Protected with encryption at rest, access controls and physical security.
Data in use
Data being actively processed: open in an application, held in RAM, being read, edited or calculated. Protected with access controls, authentication and screen locking.

One piece of data passes through all three states: a customer record is at rest in the database, in transit when sent to a sales assistant's device, and in use while it is open on screen.

2.3.2  Data stores

A data store is a repository for persistently storing and managing collections of data, such as a database, a file system, a spreadsheet, a data warehouse or a cloud storage service.

Purpose: keep data safely so it is not lost when power is off; organise it so it can be found, searched and retrieved; control who can access it; and make it available to the applications and people that need it.

How data stores interact: data is passed between stores, for example a sales database feeds a data warehouse each night, a spreadsheet imports a CSV export from a database, or an application reads from a cloud store through an API. In the pipeline, the capture phase writes into stores and the analysis and use phases read from them. Interaction needs compatible formats and secure connections.

2.3.3  Data storage types: block, file and object

Block storage
Data split into fixed-size blocks, each with a unique address; the operating system reassembles them. Used by SANs, databases and virtual machines. Benefits: Very fast and low latency; good for data that changes often. Limitations: Expensive; little metadata; harder to scale and share than object storage.
File storage
Data stored as whole files in a hierarchy of folders, found by a file path. Used by file servers, NAS and PCs. Benefits: Simple and familiar; easy to share across a network. Limitations: Slows down as millions of files build up; harder to scale.
Object storage
Data stored as objects in a flat pool, each with the data, rich metadata and a unique ID. Used by cloud services for photos, video, backups and archives. Benefits: Scales almost without limit; cheap for large volumes; metadata helps searching. Limitations: Slower; objects are replaced rather than edited, so poor for frequently changing data such as databases.

Factors when selecting: speed needed, how often data changes, volume and growth, cost, how it will be accessed and shared, and security requirements.

2.3.4  On-site storage

File servers
A dedicated computer on the network that stores and shares files for users. Benefits: Central storage, backup and access control. Limitations: Hardware cost; needs IT staff to manage; single point of failure.
Hard disk drive (HDD)
Magnetic storage on spinning platters read by a moving head. Benefits: Cheap per GB; large capacities. Limitations: Slower; moving parts can fail if dropped; noisy.
Solid state drive (SSD)
Flash memory with no moving parts. Benefits: Much faster access; robust; silent; low power. Limitations: Higher cost per GB; limited number of write cycles.
Network attached storage (NAS)
A storage device with its own drives that connects directly to the network and shares files. Benefits: Simple to set up for small organisations; shared access; supports backups; can allow remote access. Limitations: Limited scalability; speed depends on network bandwidth; must be physically secured.
Portable storage devices
USB flash drives, external hard drives, memory cards. Benefits: Cheap, small, easy to move data between devices. Limitations: Easily lost or stolen; malware risk; must be encrypted.
Storage area network (SAN)
A separate high-speed network of storage devices that servers see as local drives (block storage) Benefits: Very fast; highly scalable; good for large databases. Limitations: Expensive; complex; needs specialist staff.

Factors when selecting on-site storage: capacity, speed, cost, number of users, need for remote access, scalability, security, and whether the organisation has IT staff.

OCR's 6-mark "Should the company use a NAS?" question is levels-marked. Top band needs benefits and limitations applied to the scenario, plus a clear conclusion with reasons. For a seven-person office with no IT staff, credited points include: simple to set up, supports office applications, easy collaboration, cheaper than a large server, limited scalability if staff grow, and needs physical security.

2.3.5  Cloud storage

Public
Provider's infrastructure shared by many organisations (multi-tenant), accessed over the internet, pay as you go. Benefits: No hardware to buy; scales up and down quickly; provider handles maintenance and security staff. Limitations: Less control over data and its location; depends on internet access; shared resources can increase latency.
Private
Infrastructure used by one organisation only, on-site or hosted; accessed through an intranet or with permission levels over the internet. Benefits: Most control and security; customisable; easier to meet strict compliance. Limitations: Expensive to set up and run; needs specialist staff; scaling needs new hardware.
Hybrid
A mix of private and public cloud, with data and applications moved between them. Benefits: Sensitive data kept private while public cloud handles peaks; flexible. Limitations: Complex to manage and secure; integration costs.
Community
Shared by several organisations with common needs, e.g. NHS trusts, schools in a trust, councils. Benefits: Costs shared; meets the group's shared compliance needs. Limitations: Less control than private; agreement needed on how it is run; limited capacity.

Cloud-based database services (Database as a Service, DBaaS): a provider hosts and manages a database in the cloud, handling installation, backups, updates and scaling. Uses: website and app back ends, storing customer and transaction data, analytics on large data sets, and sharing data between sites. The organisation pays for what it uses and does not need database servers of its own.

Factors when selecting: sensitivity of the data, legal requirements (where data is stored), cost, scalability, reliability and uptime, security offered, internet connectivity, and the skills of the organisation's staff.

OCR's indicative content for "analyse the impacts of a public cloud" on a new company includes: no hardware investment; flexible plans; large providers employ experienced security staff; risk of downtime and denial-of-service; loss of control over data; reliance on the provider for backups; multitenancy increasing latency; and data stored abroad raising legal issues.

2.4  Data transformation: wrangling and maintenance

Data wrangling
Purpose: to transform and prepare raw data from one or more sources into a format that can be analysed or used by a computer system or application.
Importance: raw data is often messy, inconsistent and in different formats. Wrangling makes it accurate and consistent, so analysis gives reliable results. It is time-consuming but essential.
Data maintenance
Purpose: to keep stored data accurate, complete, up to date, secure and usable over time.
Importance: data goes out of date (people move, prices change). Maintenance keeps decisions based on current data, avoids errors and duplicates building up, meets the legal duty to keep personal data accurate, and keeps data useful.

Not in F200: specific data wrangling activities and specific data maintenance activities. (F201 covers data cleaning techniques.)

2.5  Usage and analysis: data analytics

Data analytics is examining data to draw conclusions from it. Its purpose is to apply statistical analysis and technologies to data to find trends and solve problems, so organisations can make informed decisions. (These two words complete the sentence on OCR's sample paper.)

Descriptive
Question it answers: What happened? When it could be used: Monthly sales reports, website visitor totals, dashboards of past performance. Benefits: Simple; summarises large data sets clearly. Limitations: Does not explain why or predict the future.
Diagnostic
Question it answers: Why did it happen? When it could be used: Finding why sales fell in one region, why customers cancelled. Benefits: Finds causes and relationships so problems can be fixed. Limitations: Needs detailed data and skilled analysts; correlation is not always cause.
Predictive
Question it answers: What is likely to happen? When it could be used: Forecasting demand, predicting which customers will leave, credit risk. Benefits: Lets an organisation plan ahead. Limitations: Predictions are probabilities, not certainties; relies on past patterns continuing.
Prescriptive
Question it answers: What should we do? When it could be used: Recommending prices, best delivery routes, stock reorder levels. Benefits: Recommends specific actions and their likely outcome. Limitations: Complex and expensive; depends on accurate predictive models.
Cognitive
Question it answers: Uses AI and machine learning to mimic human reasoning, learning from data and handling unstructured data such as text and speech. When it could be used: Chatbots, analysing customer reviews, medical diagnosis support. Benefits: Analyses unstructured data; improves as it learns. Limitations: Very expensive; needs huge data sets; decisions can be hard to explain and may be biased.

The four main types build on each other: descriptive (what), diagnostic (why), predictive (what next), prescriptive (what to do). Cognitive adds AI on top. Match the type to the question the scenario is asking.

2.6.1  Presenting data

Graphical (charts, graphs, diagrams)
Trends and comparisons seen at a glance; engaging; good for non-specialist audiences. Limitations: Exact values are hard to read; can mislead with poor scales; not suitable for very detailed data.
Tabular (rows and columns)
Shows exact values; easy to look up and compare individual figures. Limitations: Trends are hard to see; large tables overwhelm readers.
Textual (written explanation)
Explains context, reasons and conclusions; good for recommendations. Limitations: Slow to read; patterns in numbers are hard to show in words.

Criteria for selecting a presentation method: the audience and their expertise, the purpose (compare, show a trend, show exact values, explain), the type and amount of data, accessibility (colour blindness, screen readers), and how it will be delivered (printed, on screen, in a meeting).

2.6.2  Visualising data

Data visualisation communicates information by turning data into visual forms, so the audience can understand trends, patterns and comparisons quickly.

Dashboards
Key figures on one screen; can update in real time; interactive filters. Limitations: Can be cluttered; costly to build; needs reliable live data.
Data tables
Exact values; can be sorted and filtered. Limitations: Trends not obvious.
Digital slides
Good for presenting to a group; combine charts and key points. Limitations: Limited detail per slide; needs a presenter to explain.
Infographics
Easy to view and remember; shareable on social media; no language barrier; can use templates. Limitations: Simplifies data, so detail is lost; can be time-consuming to design well.
Reports
Detailed analysis with conclusions and recommendations; permanent record. Limitations: Long and slow to read.
Shared documents
Several people view and edit at once; always the latest version. Limitations: Version and access control needed; security risk if shared too widely.
Tables
Simple, clear layout of values for comparison. Limitations: Not visual enough for trends.
Video / online conferencing
Present and discuss findings live with remote audiences; questions answered immediately. Limitations: Depends on connection quality; time zones; harder to read detailed charts.
Area
Change in totals over time, showing volume (e.g. cumulative sales)
Bar
Comparing values across categories (e.g. sales per product)
Bubble
Three variables at once: x, y and bubble size.
Line
Trends over time (continuous data)
Pie
Proportions of a whole, with a small number of categories.
Scatter
The relationship (correlation) between two numeric variables.

Criteria for selecting a visualisation method: what the data shows (comparison, trend, proportion, relationship), the audience, the amount of data, whether it must update live, the medium, and accessibility.

Sample paper: a college wants to show what proportion of students travel by car, bus or train. Answer: pie chart, because it shows proportions of the total and suits a small data set.

2.7  Archival

Archiving moves data that is no longer in active use to separate long-term storage, where it is kept safely and can be retrieved if needed.

Importance: legal and regulatory requirements to keep records (financial, medical, employment records); evidence for audits and disputes; historical analysis; frees fast, expensive primary storage and speeds up live systems; reduces the amount of data exposed in day-to-day use.

How data is archived: identify data past its active period using a retention policy, copy it to archive storage with metadata so it can be found, check the copy, remove it from the live system, and protect it with access controls and encryption.

Cloud storage
Cheap archive tiers; off-site, so safe from local disasters; scales easily; no hardware. Limitations: Ongoing subscription; retrieval can be slow or charged; depends on the provider and internet.
Network storage
Archive on NAS or a SAN within the organisation's network; fast to retrieve; organisation keeps control. Limitations: Hardware and maintenance costs; same site as live data, so a fire or flood can destroy both.
On-site
Archive on drives, tapes or servers held on the premises; full physical control; no ongoing fees. Limitations: Physical space and security needed; media degrade over time; risk from local disasters.

2.8  Destruction

Importance of data destruction: UK GDPR's storage limitation principle says personal data must not be kept longer than needed; deleting a file normally only removes the pointer, so data can be recovered from discarded drives; secure destruction prevents breaches, identity theft and fines; and it frees storage.

Degaussing
A strong magnetic field scrambles the magnetic domains on magnetic media (HDDs, tapes) Benefits: Fast; destroys all data on the drive at once. Limitations: Drive cannot be reused; does not work on SSDs or flash memory; equipment is expensive.
Drive destruction
Physically crushing, drilling or breaking the drive so it cannot be read. Benefits: Certain and visible; works on any drive type. Limitations: Drive cannot be reused; data on surviving platter or chip fragments may be recoverable if not done thoroughly.
Erasure
Software securely wipes all data on the drive and verifies it is gone, often producing a certificate. Benefits: Drive can be reused or resold; evidence of destruction for compliance. Limitations: Takes time; must use software suited to the drive type; faulty sectors may not be wiped.
Overwriting
Replaces the existing data with zeros or random patterns, in one or more passes. Benefits: Drive can be reused; cheap. Limitations: Slow on large drives; data in areas not overwritten may remain.
Shredding
An industrial shredder cuts drives (or paper records) into tiny pieces. Benefits: Very secure; handles large volumes; works on SSDs. Limitations: Drive cannot be reused; specialist equipment or a contractor needed.

Not in F200: non-secure destruction methods (such as simply deleting files or emptying the recycle bin).

Match the method to the media and whether the drive will be reused. Degaussing is useless on an SSD; erasure or overwriting keeps the drive; destruction and shredding are for drives that will never be reused.

Topic 3 - How data can be accessed and managed across platforms

3.1  Application Programming Interfaces (API)

An API is a set of rules that lets one application communicate with another, defining how requests for data or services are made and how responses are returned. Role: APIs let data be shared and accessed across platforms (web, mobile, cloud) without each system knowing how the other works inside, and they control what data is exposed, which supports security.

API certifications (who is allowed to use the API):

Public
Open API that allows external users to access data or services, e.g. a weather or maps API. Used to encourage third-party apps. Benefit: wide reach. Limitation: harder to control misuse; needs rate limits and keys.
Partner
Provides restricted access, intended for specific purposes, to approved business partners under an agreement, e.g. a travel site reading an airline's seat availability. Benefit: controlled sharing. Limitation: agreements and access management needed.
Internal
Used only inside one organisation to connect its own systems, e.g. the stock system talking to the sales system. Benefit: secure and can be changed freely. Limitation: no outside benefit.
Private
Restricted to the organisation's own developers and applications, e.g. the back end serving the company's own mobile app. Benefit: full control and protects intellectual property. Limitation: no third-party integration; all costs fall on the organisation.
Composite
Combines several API calls into one request, e.g. creating a customer, an order and a payment in one call. Benefit: fewer requests, faster. Limitation: more complex; one failure can affect the whole request.

API types and the data format each uses:

JSON-RPC
Data format: JSON. Benefits: Lightweight and simple; calls a named function on the server. Limitations: Fewer standards for security and error handling.
REST (Representational State Transfer)
Data format: Usually JSON; can also use XML and others. Benefits: Most widely used; uses standard HTTP methods; flexible and scalable. Limitations: Fewer built-in security and reliability standards than SOAP.
SOAP (Simple Object Access Protocol)
Data format: XML only. Benefits: Strict standards with built-in security and error handling; used in banking and enterprise systems. Limitations: Verbose XML is slower and more complex.
XML-RPC
Data format: XML. Benefits: Simple way to call a function on another system. Limitations: Verbose; older and less used now.

Not in F200: a detailed understanding of how the different API types work.

Sample paper match: "provides restricted access, intended for specific purposes" is Partner; "allows external users to access data or services" is Public.

3.2  User access controls

Mandatory Access Control (MAC)
Access is set centrally by the system/administrator using security labels; users get access based on their clearance level and need to know; users cannot change access. The most secure model. When it is used: Government, military, organisations holding highly sensitive data.
Discretionary Access Control (DAC)
The owner of a file or resource decides who can access it and what they can do. When it is used: Small organisations, shared documents; flexible but less secure.
Role-Based Access Control (RBAC)
Permissions are given to roles (job titles); users get the permissions of their role. When it is used: Most businesses, schools, hospitals; easy to manage when staff change jobs.
Attribute-Based Access Control (ABAC)
Access decided by attributes of the user (department, clearance), the resource (sensitivity) and the environment (time, location, device) When it is used: Large or complex organisations needing fine-grained, flexible control, e.g. "doctors can view records of their own patients, on site, during their shift".
Rule-Based Access Control (RuBAC)
Access decided by rules set by an administrator that apply to all users, e.g. no access outside 08:00 to 18:00, or only from the office IP range. When it is used: Firewalls, time-restricted systems, networks needing blanket rules.

Sample paper: a government office storing highly sensitive data should use MAC. OCR credits reasons such as "access based on the user's level of clearance", "MAC is the most secure model", "access granted on a need-to-know basis" and "access cannot be altered by any user".

3.3  Permissions

A user works with data within the rights they have been given. An administrator controls the system: they allocate access controls and privileges to users, and so decide what each user can do.

Read
View or open data but not change it. For staff who only need to look up information.
Write
Create new data or files, e.g. add new entries to a stock file.
Edit
Change existing data, e.g. correct an error in a record.
Delete
Remove data or files. Given to very few users because of the risk of loss.

Administrator rights:

  • Allocating access controls: choosing and applying the access control model (MAC, DAC, RBAC, ABAC, RuBAC) and setting who can reach which systems.
  • Allocating user privileges at three levels:
    • User level: rights given to one individual account, e.g. one manager can approve refunds.
    • User group level: rights given to a group, and every member inherits them, e.g. all Sales staff can read the customer database. Quicker to manage for many users.
    • File and folder level: rights attached to a specific file or folder, e.g. only HR can open the Payroll folder. Gives the finest control over sensitive data.

Sample paper: a database administrator who adds data and pictures to a stock file needs rights such as read (to access the stock file) and write (to create new entries). Each right needs its own reason linked to the duty.

Topic 4 - Legal considerations

4.1  Legislation and the role of the ICO

Computer Misuse Act (CMA) 1990, as amended
Latest version: the 1990 Act as amended by the Police and Justice Act 2006 and the Serious Crime Act 2015.
Main purpose: makes unauthorised access to computer systems and data a criminal offence, so it protects data held by organisations from hackers.
Important aspects: offences of unauthorised access to computer material; unauthorised access with intent to commit a further crime; unauthorised acts that impair a computer (including spreading malware and deleting data); and making or supplying tools for these offences.
Complying: only access data and systems you are authorised to; set and log access rights; get written permission before any testing.
Non-compliance: criminal prosecution, fines and imprisonment.
Data Protection Act (DPA) 2018
Latest version: the DPA 2018, which works alongside the UK GDPR and has been amended by the Data (Use and Access) Act 2025.
Main purpose: controls how personal data is used by organisations, businesses and government, and gives individuals rights over their data. It is the UK's implementation of data protection law alongside the UK GDPR.
Complying: only collect personal data with a lawful reason; keep it accurate, secure and no longer than needed; answer subject access requests; report serious breaches to the ICO.
Non-compliance: ICO enforcement notices and fines, compensation claims, reputational damage.
Freedom of Information Act (FOIA) 2000
Latest version: the Freedom of Information Act 2000, fully in force since January 2005. It covers public authorities in England, Wales and Northern Ireland; Scotland has its own Freedom of Information (Scotland) Act 2002.
Main purpose: gives people a right of access to recorded information held by public authorities (government departments, councils, NHS, state schools, police).
Important aspects: anyone can make a written request; the authority must normally respond within 20 working days; some information is exempt (e.g. personal data, national security); public authorities must publish certain information proactively.
Complying: keep records organised so they can be found, and respond on time.
Non-compliance: complaints to the ICO, decision and enforcement notices; destroying requested information to prevent disclosure is a criminal offence.
UK General Data Protection Regulation (UK GDPR)
Latest version: the retained EU GDPR as it applies in UK law from 1 January 2021, as amended (including by the Data (Use and Access) Act 2025).
Main purpose: protects individuals' personal data by setting the key principles, rights and obligations for processing it.
Important aspects: seven principles (lawfulness, fairness and transparency; purpose limitation; data minimisation; accuracy; storage limitation; integrity and confidentiality; accountability); rights of individuals such as access and erasure; breaches reported to the ICO within 72 hours.
Non-compliance: fines up to £17.5 million or 4% of annual global turnover, whichever is higher.
Privacy and Electronic Communications Regulations (PECR) 2003
Latest version: PECR 2003, as amended (including the 2011 changes to the cookie rules and, most recently, the Data (Use and Access) Act 2025).
Main purpose: gives people specific privacy rights in relation to electronic communications.
Important aspects: rules on marketing by email, text and phone call (consent is usually needed before sending marketing emails or texts to individuals); cookies and similar tracking need consent unless strictly necessary; security of public communications services; rules on traffic and location data.
Complying: get opt-in consent for electronic marketing and non-essential cookies, offer an easy opt-out in every message, check numbers against the Telephone Preference Service.
Non-compliance: ICO fines and enforcement notices.
Information Commissioner's Office (ICO)
The UK's independent body that upholds information rights. It regulates and enforces the DPA 2018, UK GDPR, FOIA and PECR.
Role: gives guidance to organisations and the public; keeps a register of organisations that pay the data protection fee; handles complaints; investigates breaches; carries out audits; issues warnings, reprimands, enforcement notices and fines; and can prosecute criminal offences.

Not in F200: the detailed content of each act or regulation. You need the latest version, the main purpose and important aspects, how to comply, the impact of non-compliance and the role of the ICO.

Sample paper match: privacy rights in electronic communications = PECR; protects data held by companies from hackers = Computer Misuse Act; right of access to information held by UK public authorities = Freedom of Information Act.

Topic 5 - Job roles, skills and attributes in data analytics

5.1  Job roles related to data analytics

Artificial Intelligence Scientist
Researches and develops AI models and algorithms that let systems learn from data and make predictions or decisions. Where it sits in the pipeline / DLM: Analysis (and use, through AI products); depends on data from capture and storage.
Data Analyst
Organises and studies the data to get insight for a business: cleans data, runs queries, finds trends and presents findings in reports and dashboards. Where it sits in the pipeline / DLM: Analysis and use (visualisation); usage phase of DLM.
Data Architect
Designs the overall structure of the organisation's data systems: how data is stored, integrated and flows between systems, and the standards used. Where it sits in the pipeline / DLM: Plans capture and storage; creation and storage phases of DLM, including archival and destruction policies.
Data Engineer
Builds systems and develops algorithms to transform data into useful information: builds and maintains the pipelines that collect, clean and move data. Where it sits in the pipeline / DLM: Capture, process (transformation) and storage.
Data Scientist
Uses statistics, programming and machine learning to build predictive models and answer complex questions. Where it sits in the pipeline / DLM: Analysis (predictive and prescriptive); communicates results in use.
Database Administrator
Installs, maintains and secures databases: user access and permissions, backups, performance, adding and updating data. Where it sits in the pipeline / DLM: Storage; also usage (access control), archival and destruction.
Machine Learning Engineer
Builds, trains, deploys and maintains machine learning models in live systems. Where it sits in the pipeline / DLM: Analysis and use; needs processed data from the pipeline.

Not in F200: the specific skills required for each job role, and detailed lists of responsibilities.

The two definitions in bold above are the exact phrases OCR's sample mark scheme uses for Data Analyst and Data Engineer. Do not confuse them: the analyst studies the data; the engineer builds the systems that move and transform it.

5.2  Personal attributes

Analytical skills
Breaking data down to spot patterns, errors and trends. Essential for analysts and scientists.
Effective communicator
Explaining technical findings clearly to non-technical people, e.g. an AI scientist communicating findings to others.
Independence
Working without constant supervision, e.g. an engineer fixing a failed pipeline overnight.
Leadership
Guiding a team and making decisions, e.g. a data architect setting standards others follow.
Planning and organisation skills
Scheduling work, managing projects and keeping data and documentation in order.
Problem solving
Finding solutions to technical and business problems, e.g. an AI scientist designing models and algorithms.
Self-motivation
Keeping up to date with new tools and techniques without being told.
Team working
Working with other staff: engineers, analysts and business teams depend on each other through the pipeline.
Time management
Meeting deadlines for reports and keeping time-sensitive data up to date.

The sample paper asks for one attribute for an AI Scientist and one reason. OCR credits problem solving (to design models and algorithms), team working (to work with other staff) and effective communicator (to communicate findings to others). The reason must match the attribute you gave.

5.3  Communication skills

Appropriate language to meet the needs of the audience
A data analyst presenting results to managers avoids jargon; with other engineers they can use technical terms (use phase)
Non-verbal
Body language, eye contact and tone in meetings and presentations; reading the audience's reactions when presenting findings.
Questioning techniques to elicit specific information
Open and closed questions to find exactly what data a client needs before capture (defining requirements), or to diagnose a fault.
Verbal
Meetings with colleagues, explaining findings, phone calls and video conferences.
Written
Reports, documentation, emails; entering data correctly; writing data dictionaries and user guides.

Sample paper: a database administrator's communication skill. Credited answers: verbal (for meetings with colleagues), written (for entering data correctly) or questioning techniques (to elicit specific information).

Topic 1 - The scope of managing big data

1.1  The six characteristics (6Vs)

The 6Vs are the characteristics that define data as big data. Use the spec's full wording for each one: OCR's sample mark scheme accepts "Variety of data types" but rejects "Variety" on its own.

Volume of data
The amount of data: the amount that exists, the initial size collected, and how fast the amount is growing. How it helps define big data / when it is used: Data too large for normal storage and software is big data. Used when judging storage and processing capacity, e.g. 12 million loyalty scheme members.
Variety of data types
The range of types and formats: structured, semi-structured and unstructured (text, images, video, sensor readings, form entries) How it helps define big data / when it is used: Many types from many sources means tools that can combine them are needed, e.g. an online form, transaction records and social media posts.
Velocity of streamed data
The speed at which data is generated, streamed and must be processed, often in real time. How it helps define big data / when it is used: Used when data must be acted on quickly, e.g. fraud detection on card payments, live traffic data.
Value of data
The usefulness of the data: the insight and benefit it can bring to the organisation. How it helps define big data / when it is used: Data is only worth collecting if it brings value, e.g. better decisions, more sales; used to decide what to keep and analyse.
Veracity of data
The accuracy, quality and trustworthiness of the data. How it helps define big data / when it is used: Big data is often messy; low veracity means it must be cleaned before results can be trusted, e.g. duplicate or incomplete records.
Variability of data inconsistencies
How much the data's meaning, format or flow changes and how inconsistent it is over time. How it helps define big data / when it is used: Inconsistent data (spikes in volume, a word meaning different things in different contexts) has to be handled before analysis, e.g. seasonal peaks.

Sample paper: "state two ways the volume of data can characterise data as big data". OCR credits: the amount of data that exists; the initial size of data collected; the amount of data is growing.

1.1  Six steps for analysing big data

1 Data collection
Gathering data from sources such as transactions, sensors, social media, forms and GPS. Role in managing big data: Provides the raw material; what is collected limits what can be learned.
2 Data storing
Saving the data in suitable storage: data lakes, data warehouses, cloud, NoSQL databases. Role in managing big data: Keeps large volumes secure and available for processing.
3 Data cleaning
Removing duplicates and irrelevant data, fixing errors and missing data, converting types. Role in managing big data: Raises veracity so results can be trusted.
4 Data mining
Searching large data sets to discover patterns, relationships and anomalies. Role in managing big data: Finds the hidden patterns that analysis will interpret.
5 Data analysis
Applying analytic techniques (regression, clustering, time series) to interpret the patterns. Role in managing big data: Turns patterns into insight and answers to business questions.
6 Data consumption
Presenting and using the results: dashboards, reports, visualisations, automated decisions. Role in managing big data: Results reach the people and systems that act on them, which is where the value is gained.

Learn the order. Cleaning comes before mining: mining dirty data finds false patterns.

1.2  The evolution of big data

Database management systems
Made it possible to store, organise and query large amounts of structured data efficiently. Benefits: Reliable, structured storage; fast searching with queries. Limitations: Traditional relational DBMSs struggle with unstructured data and very large scale, which led to NoSQL and distributed systems.
Internet of Everything (IoE)
Connects people, processes, data and things (devices), so huge streams of data are generated continuously. Benefits: Real-time data from every connected object. Limitations: Massive velocity and volume to manage; security and privacy risks.
Proliferation of devices generating digital data
Smartphones, wearables, smart meters and sensors mean almost every activity creates data. Benefits: Rich, varied data about behaviour and location. Limitations: Variety and variability make it hard to combine; privacy concerns.
Search engines
Index billions of pages and record every search, needing new ways to store and process data at scale. Benefits: Drove development of distributed processing; search trends are valuable data. Limitations: Raise privacy questions about tracking users.
Web-based storage
Cheap cloud storage removed the cost barrier to keeping very large volumes of data. Benefits: Scalable, pay as you go; accessible from anywhere. Limitations: Depends on internet access and providers; security and data location concerns.

1.3  How big data is captured

Big data capture is collecting data from its sources and bringing it into a system so it can be stored and analysed.

Digital images and videos
Data generated: Unstructured image and video files with metadata (time, location) When used: CCTV, medical scans, quality checks on production lines. Benefits: Rich visual detail; can be analysed by AI. Limitations: Very large files; needs AI to analyse; privacy.
GPS signals
Data generated: Location coordinates and time. When used: Delivery tracking, navigation, fitness apps. Benefits: Precise, real-time location. Limitations: Weak indoors; privacy concerns.
IoE connected devices
Data generated: Continuous streams of readings and status data. When used: Smart homes, smart meters, connected cars. Benefits: Real-time and automatic. Limitations: Huge velocity; device security weaknesses.
Natural language
Data generated: Unstructured text and speech. When used: Voice assistants, chatbots, customer reviews. Benefits: Captures opinions and meaning in people's own words. Limitations: Ambiguous; needs natural language processing.
Online surveys
Data generated: Structured answers (and some free text) When used: Customer feedback, market research. Benefits: Cheap; reach many people; easy to analyse. Limitations: Low response rates; bias in who replies.
Satellites
Data generated: Images and sensor readings of the Earth. When used: Weather forecasting, climate monitoring, farming. Benefits: Covers huge areas, including remote ones. Limitations: Very expensive; huge volumes; weather can block images.
Sensors
Data generated: Numeric readings: temperature, motion, pressure, light. When used: Manufacturing, energy management, environmental monitoring. Benefits: Accurate, continuous, automatic. Limitations: Faulty sensors give false data; maintenance needed.
Social media sites
Data generated: Posts, likes, shares, images: mostly unstructured. When used: Brand monitoring, sentiment analysis, trend spotting. Benefits: Real-time public opinion; large volume. Limitations: Unreliable or fake content; not representative.
Transactional records
Data generated: Structured data on what was bought, when, where and by whom. When used: Retail, banking, loyalty schemes. Benefits: Accurate; captured automatically at point of sale. Limitations: Shows what, not why; personal data must be protected.

1.4  The purpose, importance and use of big data analytics

Banking
Fraud detection, credit risk scoring, personalised products. Benefits: Fraud stopped in real time; fairer, faster lending decisions. Limitations: Biased models can refuse credit unfairly; very sensitive data.
Communications, media and entertainment
Recommendations, audience analysis, targeted advertising. Benefits: Viewers see content they want; more subscribers and advertising income. Limitations: Privacy concerns; "filter bubbles" narrow what people see.
Education
Tracking student progress, personalised learning, predicting who needs support. Benefits: Early support for struggling students; better resource planning. Limitations: Data on children is sensitive; risk of labelling students.
Energy and utilities
Smart meter analysis, demand forecasting, fault prediction. Benefits: Supply matched to demand; less waste; faults fixed early. Limitations: Costly infrastructure; smart meter data reveals household habits.
Government
Planning services, census and population analysis, fraud detection in benefits and tax. Benefits: Evidence-based policy; services where they are needed. Limitations: Public trust and surveillance concerns; legacy systems.
Healthcare
Disease tracking, predicting outbreaks, diagnosis support, planning hospital capacity. Benefits: Earlier diagnosis; better use of beds and staff. Limitations: Special category data; errors can harm patients.
Insurance
Risk assessment and pricing, claims fraud detection, telematics in cars. Benefits: Prices reflect individual risk; fraud reduced. Limitations: Some people priced out; discrimination risk.
Manufacturing
Predictive maintenance, quality control, supply chain optimisation. Benefits: Less downtime; fewer defects; lower costs. Limitations: Expensive sensors and skills; integration with old machinery.
Retail
Customer behaviour analysis, stock management, personalised offers, pricing. Benefits: Right stock in the right store; higher sales; loyal customers. Limitations: Customers may find tracking intrusive; poor data gives wrong orders.

F201 has one scenario that develops through the paper (the sample uses a large retailer with a loyalty scheme). Every PO2 answer needs a second clause applying the point to that scenario, e.g. "stock levels can be monitored (1) so the retailer can order more of its popular products (1)".

Topic 2 - The infrastructure challenges of big data

2.1  Types of big data

Structured data
Organised in a fixed, predefined format (rows, columns, fields), so it is easy to search and analyse. Examples in the spec: continuous data (measured, any value in a range, e.g. temperature), discrete data (counted, set values, e.g. number of items), relational database data, spreadsheet file data and transactional data.
Unstructured data
Has no predefined format or model, so it is hard to store in tables and needs advanced tools to analyse. Examples in the spec: social media and entertainment data (posts, images, videos, music) and weather data (satellite images, radar).
Semi-structured data
Not in fixed tables, but contains tags or markers that give it some organisation. Examples in the spec: emails (structured headers such as To, From, Date, with an unstructured body), XML, zipped files and web pages (HTML tags around free content).
Structured
How captured: Forms, tills, sensors, database entry. Purpose / when used: Reporting, transactions, statistics. Benefits: Easy to query, sort and analyse; smaller storage. Limitations: Rigid; cannot hold rich content like images.
Unstructured
How captured: Cameras, social media, microphones, satellites. Purpose / when used: Sentiment analysis, image recognition, forecasting. Benefits: Rich detail; most of the world's data. Limitations: Large; needs AI and specialist tools; hard to search.
Semi-structured
How captured: Email systems, web servers, APIs, file exports. Purpose / when used: Data exchange between systems, web content. Benefits: Flexible; tags make it partly searchable. Limitations: Needs parsing before analysis; inconsistent structure.

Sample paper: "transactional data is structured data; state two other examples". Credited: continuous data, discrete data, relational database, spreadsheet file data. Repeating transactional data gets no mark.

2.2  Data preparation and cleaning for data mining

Purpose of preparing data: to get raw data into a consistent, accurate form so mining and analysis give reliable results.

  • Numeric data is prepared by setting consistent units and decimal places, converting numbers stored as text into numbers, dealing with outliers and missing values, and scaling values so they can be compared.
  • Textual data is prepared by making case and spelling consistent, removing extra spaces and punctuation, splitting text into words or fields, translating, and grouping words with the same meaning.

Data wrangling transforms and prepares raw data from one or more sources into a format that can be analysed or used by a computer system or application. It can be time-consuming but is essential for obtaining reliable results from data analysis. It is used to prepare data by combining sources, restructuring, cleaning, enriching and validating it. (The three bold words complete the sample paper's sentence.)

Purpose of cleaning data: to remove or correct inaccurate, incomplete, duplicated and irrelevant data so the results can be trusted.

Removing duplicates
When to use it: The same record appears more than once (e.g. a customer registered twice) Benefit: Counts and totals become accurate. Limitation: Near-duplicates with small differences are hard to detect.
Removing irrelevant data
When to use it: Data not needed for the analysis (fields or records outside scope) Benefit: Smaller, faster data set focused on the question. Limitation: Risk of removing data that later turns out to be useful.
Converting data type
When to use it: Numbers or dates stored as text. Benefit: Values can be calculated and sorted correctly. Limitation: Conversion can fail or lose data if formats vary.
Clear formatting
When to use it: Data imported with fonts, colours, hidden characters or mixed formats. Benefit: Consistent data that software reads correctly. Limitation: Loses formatting that carried meaning (e.g. highlighting)
Fix structural errors
When to use it: Typos, inconsistent naming or capitalisation, wrong formats (e.g. an email without @) Benefit: Categories group correctly. Limitation: Time-consuming; needs rules for what is "correct".
Language translation
When to use it: Data collected in more than one language. Benefit: All data can be analysed together. Limitation: Meaning and tone can be lost; cost of translation.
Fix missing data
When to use it: Empty fields (e.g. a missing postcode) Benefit: Records become complete and usable. Limitation: Filling gaps with estimates can introduce errors; deleting records loses data.
Validate data
When to use it: Check cleaned data against rules (range, format, type) Benefit: Confirms the data is sensible before analysis. Limitation: Cannot prove the data is actually correct.

Not in F201: technical details of each data cleaning technique.

Sample paper: loyalty records with one customer listed twice, a missing postcode and an email address without an @. Credited techniques: removing duplicates, fix missing data, fix structural errors. Read the data given and match each problem to a technique.

2.3  Data mining techniques

Data mining is the process of searching large data sets to discover hidden patterns, relationships and anomalies that can be used to make decisions. Its role in analysing big data is to find the patterns that would be impossible to spot by hand.

Descriptive
Summarises past data to find patterns: groupings, associations, frequent combinations. When used: Finding products bought together, grouping customers. Benefits to organisations: Clear picture of what has happened. Limitations: Does not explain causes or predict.
Diagnostic
Drills into data to find why something happened, using correlations and anomalies. When used: Why sales fell, why a machine failed. Benefits to organisations: Causes can be fixed. Limitations: Correlation may be mistaken for cause.
Predictive
Uses historical patterns and statistical or machine learning models to forecast outcomes. When used: Demand forecasting, predicting customer churn, fraud scoring. Benefits to organisations: Plan ahead; act before problems happen. Limitations: Only probabilities; patterns can change.
Prescriptive
Uses predictions plus rules or optimisation to recommend the best action. When used: Pricing, routing, stock replenishment. Benefits to organisations: Specific recommended actions. Limitations: Complex, costly; depends on accurate predictions.

Not in F201: coding details.

2.4  Big data infrastructure: server configurations

Dedicated servers
Characteristics: one physical server used by a single organisation or task, with all its resources reserved.
When used: moderate data volumes, sensitive data, predictable workloads.
Benefits: full control, consistent performance, good security because nothing is shared.
Limitations: limited capacity; scaling means buying a bigger machine; single point of failure.
Distributed cluster of servers
Characteristics: many servers (nodes) linked to act as one system, with data and processing split across them and run in parallel.
When used: very large volumes and high velocity data, e.g. search engines, streaming services.
Benefits: scales by adding nodes; processes in parallel so is faster; fault tolerant because work moves to other nodes if one fails.
Limitations: complex to set up and manage; needs specialist staff; network delays between nodes.

Factors influencing the choice: volume and growth of data, velocity (real-time needs), processing power required, reliability and fault tolerance, security and compliance needs, scalability, staff skills available.

Not in F201: costs of implementation.

2.4  Big data infrastructure: software platforms

Open-source software
Source code freely available to use and modify; community developed. When used: Organisations wanting flexibility or low licence costs. Benefits: No licence fee; customisable; large communities. Limitations: Support relies on the community or paid third parties; needs in-house skills.
Vendor-specific software
Proprietary software from one company, with its own licence and support. When used: Organisations wanting a supported, integrated package. Benefits: Professional support; tested and integrated. Limitations: Licence costs; locked in to one vendor.
Data visualisation software
Creates charts, graphs and interactive dashboards from data. When used: Presenting results to managers and meetings. Benefits: Visualise data instead of raw figures; real-time monitoring; charts can be shared across departments. Limitations: Incorrect data or the wrong chart type misleads; cluttered output may not suit the audience.
Data analytics software
Applies statistical and analytic techniques to find trends and patterns. When used: Making informed decisions from large data sets. Benefits: Fast, accurate analysis of huge volumes. Limitations: Needs skilled users; results only as good as the data.
NoSQL database
Non-relational database that stores data as documents, key-value pairs, graphs or wide columns, with flexible schemas. When used: Unstructured and semi-structured big data, high-velocity web apps. Benefits: Scales across clusters; handles varied data types. Limitations: Less suited to complex queries and strict consistency than relational databases.
Data integration platforms
Combine data from many sources into one consistent view (extracting, transforming and loading data) When used: Bringing together data from different departments or systems. Benefits: Single view of the data; automates data movement. Limitations: Complex to set up; errors spread to every system downstream.

OCR's sample mark scheme for "one benefit and one limitation of data visualisation software" credits, for example: charts and graphs can be created so the retailer can visualise data rather than look at raw data; and the output may be cluttered or not fit for the audience, so the retailer struggles to extract the relevant results.

2.4  Big data infrastructure: data storage areas

Public cloud
Provider's infrastructure shared by many customers, accessed over the internet. When used: Variable or fast-growing workloads. Benefits: Scales on demand; no hardware to buy. Limitations: Less control; data location and security concerns; internet dependent.
Private cloud
Infrastructure only accessible to one organisation, accessed through an intranet or with permission levels remotely through the internet. When used: Sensitive data needing control. Benefits: Control, security, customisation. Limitations: Higher staff and maintenance costs; access fails if systems or internet fail.
Data lake
Stores huge amounts of raw data in its original format (structured, semi-structured and unstructured) until it is needed. When used: Data scientists exploring data; machine learning. Benefits: Keeps everything; cheap per GB; flexible. Limitations: Can become a disorganised "swamp"; quality not guaranteed.
Data warehouse
Stores cleaned, structured data from many sources, organised for querying and reporting. When used: Business reporting and analysis. Benefits: Consistent, high-quality data; fast queries. Limitations: Less flexible; structure must be designed in advance; costly.
Solid state drives (SSDs)
Flash storage with no moving parts. When used: Where fast access to data is needed, e.g. real-time analytics. Benefits: Very fast; reliable; low power. Limitations: Higher cost per GB than HDD.
Blockchain (emerging)
A distributed ledger where records are stored in linked blocks copied across many computers. When used: Records that must not be altered, e.g. transactions, supply chains. Benefits: Tamper-resistant; no single point of failure. Limitations: Slow; energy-hungry; not suited to large files.
DNA (emerging)
Encodes digital data in synthetic DNA molecules. When used: Long-term archiving in research. Benefits: Extremely dense; can last for very long periods. Limitations: Very slow and expensive to write and read; experimental.
Quantum server (emerging)
Uses quantum computing principles to store and process data. When used: Research into very complex problems. Benefits: Potentially huge processing power for certain problems. Limitations: Experimental; extremely expensive; error-prone; needs special conditions.

Not in F201: providers of data lakes and data warehouses.

Lake = raw data in any format, stored first and shaped later. Warehouse = cleaned, structured data, shaped first. Sample paper credits any of public cloud, data lake, data warehouse or SSDs as "another storage area" to private cloud.

2.5  Data science and data analytics

Data science
Purpose: to use statistics, programming, machine learning and AI to extract knowledge from data and build models that predict and automate. It is the wider field, asking open questions and creating new methods and algorithms.
Data analytics
Purpose: to examine data to answer specific questions, find trends and patterns and help decision making; in OCR's words, to help an organisation make sense of collected data. It is narrower and focused on business questions.

Difference: data science builds the models and tools and looks for questions worth asking; data analytics applies tools to existing data to answer a defined question. Data analytics is often treated as part of data science.

Use in the areas of application (1.4): in healthcare, data science builds diagnostic models from scans while analytics reports waiting times; in retail, data science builds the recommendation engine while analytics finds the best-selling products by region; in banking, data science builds fraud models while analytics reports monthly fraud rates.

2.6  Data analytic techniques

Regression analysis
Estimates the relationship between a dependent variable and one or more independent variables, to predict one from the others. When used: How price affects sales; forecasting revenue from advertising spend. Benefits: Shows the strength of relationships; supports predictions. Limitations: Assumes the relationship holds; correlation is not cause; outliers distort it.
Monte Carlo simulation
Runs a model many thousands of times with random input values to show the range and probability of possible outcomes. When used: Risk analysis in finance, project timings, insurance. Benefits: Shows the likelihood of each outcome, not just one answer. Limitations: Needs a lot of processing; only as good as the assumptions in the model.
Factor analysis
Reduces a large number of variables to a smaller number of underlying factors that explain them. When used: Survey analysis, e.g. finding that many questions all measure "customer satisfaction". Benefits: Simplifies complex data; reveals hidden factors. Limitations: Interpreting factors is subjective; needs large samples.
Cohort analysis
Groups people who share a characteristic or experience in the same time period (e.g. customers who joined in January) and tracks their behaviour over time. When used: Customer retention, app usage, the effect of a marketing campaign. Benefits: Shows how behaviour changes over a customer's lifetime. Limitations: Cohorts must be defined carefully; needs data over a long period.
Cluster analysis
Sorts objects or data points into groups (clusters) so that members of a group are similar, to identify the degree of association. When used: Customer segmentation, grouping products, spotting unusual (possibly fraudulent) transactions. Benefits: Clear links between groups; targeted decisions; filters out irrelevant data. Limitations: Wrong data or poorly chosen groups give false associations and wrong decisions.
Time series analysis
Analyses data points recorded at regular intervals over time to find trends, seasonal patterns and cycles. When used: Sales forecasting, energy demand, stock prices, weather. Benefits: Reveals seasonality; supports forecasting. Limitations: Assumes past patterns continue; one-off events disrupt it.

Not in F201: the technical details of each technique.

The sample paper's 9-mark question was "discuss whether the retailer should use cluster analysis". Level 3 (7 to 9 marks) needs a range of examples of its use, benefits and limitations for the retailer, analysis in context and a clear conclusion with reasons. OCR's examples: links between products bought and age range, location, and online versus in store.

Topic 3 - Big data, machine learning and artificial intelligence

3.1  Artificial intelligence (AI)

Artificial intelligence (AI) is the ability of computer systems to perform tasks that normally need human intelligence, such as recognising patterns, understanding language, making decisions and learning from experience.

How AI is developed and used in data science: developers collect and prepare large training data sets, choose an algorithm, train a model on the data, test it on new data, then deploy and monitor it. In data science AI is used to find patterns in huge data sets, analyse unstructured data (images, speech, text), make predictions and recommendations, and automate decisions.

Benefits of AI in data science
Analyses volumes of data no human could; works 24/7; finds complex patterns; handles unstructured data; makes fast, consistent decisions; personalises services.
Limitations of AI in data science
Needs large amounts of good-quality data; can learn bias from its training data; decisions can be hard to explain; expensive to develop; needs specialist staff; errors can be repeated at scale.

Sample paper: "explain how AI can be used to provide recommendations". Credited: algorithms consider the customer's transaction history (1) and select products based on what was previously bought (1).

3.1  Machine learning and its algorithms

Machine learning (ML) is a branch of AI in which systems learn from data to identify patterns and make predictions or decisions, improving with experience without being explicitly programmed for each task. ML algorithms are trained on historical data, then applied to new data.

Decision Tree
A flowchart-like model that splits data with a series of yes/no questions at nodes until it reaches a decision or prediction at a leaf. Supervised (learns from labelled examples) Use for digital analysis: Approving or refusing a loan, diagnosing a fault, predicting whether a customer will buy. Benefits: Easy to understand and explain; works with numeric and category data; fast. Limitations: Can overfit (fit the training data too closely and do badly on new data); small changes in data can change the tree.
Random Forest
Builds many decision trees, each on a random sample of the data, and combines their votes (or averages) for the final answer. Supervised. Use for digital analysis: Fraud detection, credit scoring, predicting customer churn. Benefits: More accurate and less prone to overfitting than one tree; handles large data sets. Limitations: Harder to explain than one tree; slower; needs more processing power.
K-Means
Groups data into k clusters: places k centre points, assigns each data point to the nearest centre, moves each centre to the average of its points, and repeats until stable. Unsupervised (no labels needed) Use for digital analysis: Customer segmentation, grouping similar products, finding unusual data points. Benefits: Simple; fast on large data sets; finds groups without labelled data. Limitations: The number of clusters (k) must be chosen in advance; sensitive to outliers and starting points; assumes round, similar-sized clusters.

How big data, ML and AI interact in data science: big data provides the large, varied training data that machine learning needs; ML is the method by which AI systems learn from that data; AI then applies what has been learned to analyse new data and make predictions or decisions, which creates more data that can be used to retrain the model. Without big data, models are inaccurate; without ML and AI, big data is too large to analyse by hand.

Not in F201: the historical development of AI and machine learning.

Random Forest is many decision trees combined; K-Means is clustering. Decision Tree and Random Forest predict a known type of answer from labelled examples; K-Means finds groups that nobody labelled.

Topic 4 - Legal and ethical issues in data management

4.1  Legal issues: UK GDPR

Latest version: the UK GDPR is the retained EU GDPR as it applies in UK law from 1 January 2021, alongside the Data Protection Act 2018, as amended (including by the Data (Use and Access) Act 2025).

Main purpose: to protect an individual's personal data, and to set out the key principles, rights and obligations for processing personal data. (Both wordings are credited on the sample mark scheme.)

Features
Applies to personal data (information about an identifiable living person) and stricter rules for special category data (health, ethnicity, religion, biometrics). A lawful basis is needed for processing. Data controllers and processors have duties. Breaches must be reported to the ICO within 72 hours. Some organisations must appoint a Data Protection Officer. Enforced by the ICO.
Principles
Personal data must be: processed lawfully, fairly and in a transparent way; collected for specified, explicit and legitimate purposes (purpose limitation); adequate, relevant and limited to what is necessary (data minimisation); accurate and kept up to date; kept no longer than necessary (storage limitation); processed securely (integrity and confidentiality). Plus accountability: the controller must be able to show it complies.
Rights of data subjects
The right to be informed; of access (subject access request); to rectification; to erasure ("right to be forgotten"); to restrict processing; to data portability; to object; and rights in relation to automated decision making and profiling.
Marketing consent
Where consent is the basis for marketing, it must be freely given, specific, informed and unambiguous, given by a clear positive action (opt-in, no pre-ticked boxes), recorded, and as easy to withdraw as to give. Every marketing message must offer an opt-out. Individuals have an absolute right to object to direct marketing. Electronic marketing also falls under PECR.

How to comply: identify a lawful basis; collect only what is needed; keep data accurate; set retention periods; secure data with encryption and access controls; train staff; keep records of processing; carry out a Data Protection Impact Assessment (DPIA) for high-risk processing; respond to rights requests; report breaches within 72 hours.

Why compliance is important: it is a legal requirement; it protects individuals from harm; it builds customer trust; and it avoids penalties.

Impacts of non-compliance on organisations: fines of up to £17.5 million or 4% of annual global turnover, whichever is higher; increased costs for staff training and security; reputational damage and lost customer trust; legal action and compensation claims; business disruption; regulatory investigations by the ICO.

How organisational policies mitigate non-compliance: a data protection policy, retention and destruction policy, access control and acceptable use policies, breach response procedure, consent and marketing policy, and regular training and audits make compliance a routine part of work and provide evidence for accountability.

Not in F201: the detailed content of the regulation.

OCR's sample mark scheme quoted the EU figure of 20 million (euros). The UK GDPR maximum is £17.5 million or 4% of annual global turnover, whichever is higher. Use the UK figure, and in a 6-mark analysis tie each impact to the scenario (e.g. 250 stores means many staff to retrain).

4.2  Ethical issues: automated decision making

Automated decision making is making a decision by technological means (an algorithm) without human involvement, e.g. approving a loan, shortlisting job applicants, choosing who receives an offer.

How it creates risks of discrimination and bias:

  • A lack of training data for certain groups means the algorithm has not learned their patterns, so it treats them poorly.
  • The person creating the algorithm has unconscious bias, which is built into the final algorithm.
  • Historical data used for training already contains past bias, which the algorithm learns and repeats.

How UK GDPR applies in organisations: people must be told when significant decisions about them are made solely by automated means, including profiling. Where such a decision has legal or similarly significant effects, the organisation must provide safeguards: the person can make representations, obtain human intervention and contest the decision. Special category data has tighter restrictions. A DPIA is expected for this kind of high-risk processing.

Impacts on individuals: unfair refusal of credit, jobs, insurance or services; discrimination against protected groups; not knowing why a decision was made; difficulty challenging it; on the positive side, faster and more consistent decisions.

The sample paper's 2-mark "explain how automated decision making could increase the risk of bias" needs a cause and an implication, e.g. "historical data used to train the algorithm may include bias (1), which is built into the patterns the algorithm learns (1)".

4.2  Ethical issues: collection, storage, ownership and sharing

Protecting the identity of individuals when collecting, storing and sharing data: collect only what is needed; anonymise data (remove identifying details so people cannot be identified) or pseudonymise it (replace identifiers with codes, kept separately); aggregate results so individuals are not visible; encrypt and access-control stored data; share only under agreements and only what the recipient needs.

How data ownership is determined: by who created or collected the data, contracts and terms and conditions (e.g. a platform's terms on user content), intellectual property and copyright law, and employment contracts (work created for an employer usually belongs to the employer). Individuals do not "own" personal data held about them in a legal sense, but UK GDPR gives them rights over it, and the organisation is the controller responsible for it.

How organisations respond: privacy notices explaining what is collected and why; consent management; data sharing agreements; retention and destruction schedules; appointing a Data Protection Officer; DPIAs before new projects; ethics review boards; staff training.

4.2  Emerging ethical debates and frameworks for ethical data management

Emerging ethical debates affecting the use of data include: facial recognition in public places; AI trained on people's data or creative work without permission; the extent of workplace monitoring; selling or sharing location and health data; children's data on apps and social media; generative AI producing false or harmful content; and who is accountable when an algorithm makes a harmful decision.

Impacts on individuals: loss of privacy, feeling watched, discrimination, misuse of their data or work, and loss of trust in organisations. How organisations respond: publish AI and data ethics policies, carry out impact assessments, keep a human involved in significant decisions, be transparent about how algorithms are used, and allow people to opt out.

Data ethics framework
A set of principles and actions an organisation follows to make sure its use of data is ethical, lawful and fair. The UK government's Data Ethics Framework, for public sector projects, is built on the principles of transparency, accountability and fairness. Organisations use a framework to assess a project at the start and review it as it runs: why the data is being used, whether it is lawful, the quality and limits of the data, who could be harmed, and how decisions can be explained.
Inclusive data principles
Principles that make sure data represents everyone so no group is left out or disadvantaged. OCR's sample mark scheme credits: all population groups must be included in the data; the data must be up to date; the data must be transparent (the selection process is fair and available to anyone who asks to see it). Applied when sampling, e.g. choosing customers to survey from transaction records.

Sample paper: a retailer selects customers for a questionnaire using transaction records. "All population groups must be included" is needed so views are representative and do not show bias against a group; "up to date" so questionnaires go to current members who actually bought the product.

Topic 5 - Environment and society

5.1  Environment

Accuracy of weather forecasting
Data from satellites, weather stations, buoys, aircraft and radar is fed into computer models. Benefits: More accurate, longer-range forecasts; earlier severe weather warnings. Limitations: Needs supercomputers; forecasts remain probabilities; gaps in data from some regions.
Natural disaster management
Sensors, satellite images, social media posts and phone location data predict and track floods, wildfires and earthquakes. Benefits: Early warnings; rescue teams sent to where people are; evacuation planning. Limitations: Networks may fail during a disaster; false alarms reduce trust; privacy of location data.
Energy efficiency
Smart meters and building sensors show when and where energy is used; AI switches systems on and off. Benefits: Lower energy use and costs; supply balanced with demand. Limitations: Installation costs; patterns change (e.g. new working patterns) so algorithms can be wrong; device malfunctions.
Environmental management
Monitoring air and water quality, deforestation, wildlife and pollution with sensors and satellites. Benefits: Problems detected quickly; evidence for regulation. Limitations: Expensive monitoring networks; data quality varies by country.
Platforms to combat climate change
Shared data platforms model climate, track emissions and measure the effect of policies. Benefits: Evidence for decisions; organisations and countries can compare progress. Limitations: Data centres themselves use a lot of energy; incomplete emissions data.
Emerging environmental developments affected by big data
Precision farming (sensors and drones guide water and fertiliser use), smart grids, electric vehicle charging management. Benefits: Less waste of resources; higher efficiency. Limitations: High set-up costs; depends on reliable connectivity.

Sample paper: one benefit and one limitation of big data for warehouse energy efficiency. Credited benefit: analysis shows when and where the warehouse is used (1) so energy can be managed in those areas at those times (1). Credited limitation: patterns from normal working days may change (1), so the algorithm is wrong and energy is wasted (1).

5.2  Society

A smart city is an urban area that uses data from connected sensors, devices and systems to manage resources and services efficiently and improve the quality of life of the people living there.

How data from a variety of sources is exchanged to optimise city operations: traffic sensors, CCTV, public transport GPS, smart meters, waste bin sensors, air quality monitors and residents' apps send data over networks to central platforms. The data is shared between services (transport, energy, police, councils), analysed in real time, and used to adjust systems automatically, e.g. changing traffic light timings, rerouting buses or scheduling bin collections only when bins are full.

Benefits of a smart city
Less congestion and pollution; lower energy use; faster emergency response; better public transport; services planned around real demand; safer streets.
Limitations of a smart city
Very expensive to set up and maintain; surveillance and privacy concerns; cyber attacks could disrupt city services; people without smartphones or internet access miss out; reliance on technology that can fail.
Personalised healthcare
Treatment tailored to a person's health records, genetics and wearable data; earlier diagnosis and remote monitoring. But sensitive data must be protected, and access is unequal.
Smart homes
Heating, lighting and security controlled automatically or remotely, saving energy and helping elderly or disabled people live independently. But devices collect data about daily routines and can be hacked.
Traffic management
Shorter journeys, live travel information and fewer accidents. But journeys are tracked, and errors cause congestion.
Urban and community planning
Housing, schools, transport and green spaces planned around real data on how people live and travel. But groups underrepresented in the data can be overlooked.