chapter eighteen
18 Statistical dispersion methods
This chapter covers
- Measures of statistical dispersion
- Variance method
- Standard deviation method
- Range method
- Mean absolute deviation method
- Median absolute deviation method
- Computing churn
- Creating pyramid plots
- Running replacement operations with character strings
Our primary purpose here is to introduce several methods of statistical dispersion. Otherwise known as statistical variability or spread, statistical dispersion is a measure of how much, or not so much, a vector of continuous data is spread out or scattered around a middle value. It’s oftentimes not enough to just know the mean or median; knowing the methods by which to compute statistical dispersion are essential for gaining a true understanding of numeric data, with practical implications around assessing risk and measuring consistency and volatility frequently on the line.
Here's the context for us: