Chapter 3 of 10All chapters
Chapter 3 of 10
Spread
How far things sit from the middle.
Measures
Range is largest minus smallest and is decided by two points. The interquartile range covers the middle half and ignores extremes. Standard deviation is the typical distance from the mean.
- Two datasets can share a mean and be nothing alike.
- Variance is the standard deviation squared, and lives in squared units.
Percentiles
The value below which a given percentage falls. The 95th percentile of a response time describes the experience your unhappiest users actually have.