Simpson’s Paradox: Beware the Lurking Variable

The text discusses the concept of Simpson's Paradox, a phenomenon where a trend appears in different groups of data but disappears or reverses when these groups are combined. This paradox can lead to misleading conclusions if not carefully analyzed by considering lurking variables and causality. Examples include voting patterns for the 1964 Civil Rights Act, graduate school admissions at Berkeley, support for political candidates, kidney stone treatment success rates, and overall earnings in the US economy. The key takeaway is that numbers must be analyzed beyond face value to account for all possible influences and construct a coherent story about how these measurements came about.