Descriptive Statistics

What the resources cover

This unit sits in the Descriptive Statistics strand of Statistics and probability. The resources move through the usual path of summarising data: what kind of data you have, where its centre lies, how spread out it is, and what shape it takes.

• Data types: the Data Types mind map separates quantitative and categorical data, then breaks them into nominal, ordinal, continuous, discrete and binary.
• Centre: the notes and maps on central tendency cover the mean, median and mode, including weighted means.
• Spread: several Measures of dispersion maps explain low and high dispersion, and the Standard Deviation and Percentiles quiz tests the population formula.
• Shape: the quiz on skewed distributions asks what we call data that clusters on one side.

Where to start

Begin with the Descriptive Statistics Summary mind map. It lays out variable types, measures of centre, measures of spread, shape and outliers in one view, so you can see what you already know.

Next, pick the topic that feels weakest. If it is averages, try the quiz on the advantages and disadvantages of mean, median and mode. If it is spread, move on to the Standard Deviation and Percentiles quiz.

Using quizzes and maps together

1. Read a mind map first, to get the structure of a topic.
2. Take a related quiz without looking back at the map.
3. Return to the map for any question you missed.
4. Use a flashcard deck, such as the AP Statistics deck, to fix the key terms and formulas.

Quizzes such as the ECON 261 exam one show worked examples, like finding a median for an odd and an even number of values, so they teach as well as test.

Who it helps

Most resources are pitched at university level, with a good share suited to school students. Teachers can pick maps, notes and quizzes to share with a class.

Choose one topic today, work through a map and a quiz, and then try building a set of your own.