Simpson’s paradox

d_2018_10_06__21_40_12_PM_

Simpson’s paradox, or the Yule–Simpson effect, is a phenomenon in probability and statistics, in which a trend appears in several different groups of data but disappears or reverses when these groups are combined.

— Wikipedia on Simpson’s paradox

.

d_2018_10_05__19_25_22_PM_

— MinutePhysics

.

.

2018.10.06 Saturday ACHK