11: Describing Data
- Page ID
- 34246
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Once we have collected data from surveys or experiments, we need to summarize and present the data in a way that will be meaningful to the reader. We will begin with graphical presentations of data then explore numerical summaries of data.
- 11.2: Presenting Categorical Data Graphically
- Categorical, or qualitative, data are pieces of information that allow us to classify the objects under investigation into various categories.
- 11.6: Measures of Variation
- In addition to the mean and median, which are measures of the "typical" or "middle" value, we also need a measure of how "spread out" or varied each data set is. There are several ways to measure this "spread" of the data.