A Level Maths: Graphical Representation of Data Topic Summary and Resources
Video Lessons
Watch alongside the worksheet for the full lesson experience, then test your understanding with the lesson questions.
Revision Notes
Handwritten notes summarising the key ideas for each lesson. Ideal for quick review before a test.
Exam Questions
Past-paper-style questions organised by topic, with full mark schemes.
Drawn from OCR and Edexcel past papers but designed to be useful for students of all UK exam boards — including AQA and OCR MEI — unless a sheet is explicitly board-specific.
Before You Start This Topic
It will help if you are confident with the following:
- Averages and Spread — needed to identify median, quartiles, and IQR from these diagrams
- Statistical Sampling — provides the context for how the data was collected
- GCSE Maths Statistics — bar charts and basic frequency diagrams from GCSE are assumed
A Level Maths graphical representation of data covers the statistical diagrams you draw and interpret in the Statistics strand — histograms, box plots, cumulative frequency diagrams, and scatter diagrams. Reading these correctly is a quick win in the exam, and understanding what each diagram is good for matters for choosing appropriate methods later.
In a histogram, the area of each bar represents frequency (not the height) — this matters when class widths differ, and you compute frequency density $=$ frequency $/$ class width to draw the bars correctly. Box plots show the median, quartiles, and any outliers, giving a quick visual summary of spread and symmetry. Cumulative frequency diagrams plot the running total of frequencies against the upper boundary of each class, letting you read off the median, quartiles, and percentiles. Scatter diagrams plot pairs of values to suggest correlation between two variables, and may include regression lines for prediction (see Correlation and Regression).
Graphical representation is part of the Statistics strand of A Level Maths for AQA, Edexcel, OCR, and OCR MEI students.
Watch out for…
A few things to be careful with: in a histogram, the $y$-axis is frequency DENSITY, not frequency — multiplying frequency density by class width gives the frequency; when reading box plots, outliers (often marked with crosses) are SEPARATE from the whiskers, so do not include them when reading the range; cumulative frequency curves go through the upper class boundary, not the midpoint; and a scatter diagram showing correlation does NOT imply causation — be careful with conclusions.