Qm
Statistics

Spurious correlation: tea imports and life expectancy

spurious-correlationtrendnonstationarity

Over 40 years, a country's annual tea imports and its life expectancy both rose steadily, and their yearly levels correlate at r=0.97r = 0.97. A wellness blogger cites this as evidence that tea extends life.

Why is this correlation weak evidence, and how would you check for a real link?

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