Exploring One-Variable Data

Before you can analyze data, you need a shared language for describing what data actually looks like. This unit claims that any single-variable dataset can be characterized by its shape, center, and spread, and that choosing the right summary statistic depends entirely on the shape you observe. A skewed distribution with outliers demands the median and IQR; a symmetric one earns the mean and standard deviation. The Normal distribution is a precise mathematical model that lets you calculate the proportion of values in any interval. Every inference procedure you will meet later assumes you already know how to read a distribution and justify your choice of summary statistics.

15–23% of exam