Choosing a suitable statistical diagram
Choosing a suitable statistical diagram.
- Decide whether you want to compare categories, show parts of a whole, track time or explore paired data.
- Choose a diagram for that purpose and explain what its axes, bars or sectors represent.
Example 1
You want to compare the numbers choosing four lunch options. Suggest a suitable diagram and explain why.
The options are categories; separated equal-width bars make their frequencies easy to compare.
Example 2
You want to show how a class’s favourite sports divide up the whole class. Suggest a suitable diagram.
Each sector shows a category’s share of the same whole; sector angles total 360°.
Your turn
Temperature is recorded at noon on each of seven consecutive days. Suggest a diagram to show change over time.
Check answer
Place time on the horizontal axis and join successive readings in time order.
You record each student’s height and arm span to look for a relationship. Suggest a diagram.
Check answer
Plot one point for each paired observation. Do not join the points.
You want to display the frequency of 0, 1, 2, 3 or 4 pets per household. Suggest a suitable diagram.
Check answer
These are discrete numerical values; place the values in numerical order and show their frequencies.
A small class has a list of two-digit test marks. You want a display that keeps every individual mark. Suggest one.
Check answer
It groups values by their leading digit while retaining repeats and individual marks.
You want to compare the frequencies of four music choices in two classes. Suggest a diagram.
Check answer
Use the same frequency scale, paired bars for each category and a clear key for the two classes.
Temperature is recorded at noon on each of seven consecutive days. Suggest a diagram to show change over time.
AnswerPlace time on the horizontal axis and join successive readings in time order.
You record each student’s height and arm span to look for a relationship. Suggest a diagram.
AnswerPlot one point for each paired observation. Do not join the points.
You want to display the frequency of 0, 1, 2, 3 or 4 pets per household. Suggest a suitable diagram.
AnswerThese are discrete numerical values; place the values in numerical order and show their frequencies.
A small class has a list of two-digit test marks. You want a display that keeps every individual mark. Suggest one.
AnswerIt groups values by their leading digit while retaining repeats and individual marks.
You want to compare the frequencies of four music choices in two classes. Suggest a diagram.
AnswerUse the same frequency scale, paired bars for each category and a clear key for the two classes.