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wealth correlates with health? Except it doesn't! Why? Because the hidden variable is that wealthier people tend to be older! So you can easily construct a "pr

• grenoire 9y ago
  Overall healthiness as measured by lifespan and a cause-of-death index would help alleviate that conclusion.
• pmiller2 9y ago
  That's why you'd control for age, using an age matched control group. (As well as race, gender, and maybe a couple of other factors.)