Representing and Interpreting Data

The final stage of the data cycle is to represent the data in a picture and then interpret it.

• A bar graph uses bars whose heights show frequencies — ideal for comparing categories.
• A pictograph uses a repeated symbol, with a key telling you how many each symbol stands for (for example, one picture $= 10$ learners).

Interpreting means reading answers off the graph: totals, differences, the biggest and smallest categories, and what the data suggests. Always read the scale on a bar graph and the key on a pictograph before drawing any conclusion.

Exam checkpoint

A graph should have a title, labelled axes or categories, a sensible scale and accurate bars or points. Read the question before reading the graph: it may ask for a fact, a comparison, a difference or a conclusion. Quote data and then explain the conclusion in words.

Short worked example. If a bar chart shows 18 learners choose soccer and 12 choose netball, the difference is $18-12=6$ learners. State both the calculation and the context.