The OCR large data set gives age-band counts and the total number of usual residents for each Local Authority in 2011. A student proposes drawing 348 separate pie charts to compare the proportion of residents aged 65 or over.
Give two reasons why 348 pie charts would be difficult to use for this comparison.
Describe a more suitable statistical diagram and explain what it would show.
Explain why the age-band counts should be converted to proportions before Local Authorities are compared.
121 exam-style questions on OCR A Level Maths 2.2 Data Presentation and Interpretation, covering 2.2.1 Tables and diagrams for single variable data, 2.2.2 Area in a histogram, 2.2.3 Scatter diagrams and regression lines, 2.2.4 Informal interpretation of correlation, 2.2.5 Correlation and causation, 2.2.6 Measures of average and spread, 2.2.7 Calculations of mean and standard deviation, 2.2.8 Outliers, 2.2.9 Selecting or critiquing data presentation, and 2.2.10 Cleaning data. Each one has a worked solution and a mark scheme showing where the marks go.