Work through the list without notes. If you cannot do a statement, follow its link, then come back. Guide = study guide; Practice = practice questions.
Understanding
- I can name the five numbers in a five-number summary and say what each one marks. (Guide: “From five numbers to a picture”)
- I can explain that each section of a boxplot holds about 25% of the data, and that a longer section means more spread, not more values. (Guide: “Reading a boxplot”; Practice Q1, Q7)
- I can explain why the mean is pulled towards a long tail while the median is not. (Guide: “Shape, the mean and the median”)
- I can list what a boxplot cannot show: n, gaps, clusters and the number of peaks. (Guide: “What a boxplot cannot show”; Practice Q5)
Skills
- I can find the five-number summary of a data set with an odd or even number of values. (Guide: Worked example 1; Practice Q4)
- I can use the 1.5 × IQR fences to decide where each whisker ends. (Guide: “Outliers and where the whiskers stop”; Practice Q3, Q6)
- I can draw a boxplot on a labelled scale, with outliers marked by a separate symbol. (Guide: Worked example 1; Practice Q4)
- I can estimate the share of the data above or below any number in the five-number summary. (Guide: Worked example 2; Practice Q1)
Reasoning
- I can describe the shape of a distribution from its boxplot by comparing the lengths of its halves. (Guide: Worked example 2; Practice Q2)
- I can predict whether the mean is greater or less than the median from the shape, and the shape from the mean and median. (Practice Q2, Q6)
- I can judge whether a claim about a boxplot is correct and explain why. (Practice Q5, Q7)
All ticked? Move on to the Topic 1.9 study guide, or return to the course roadmap.