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Statistical Fallacies

Identify the most dangerous statistical fallacies that lead to wrongful convictions, failed policies, wasted research funding, and medical harm. These advanced scenarios test whether you can spot subtle errors involving Simpson's paradox, the prosecutor's fallacy, multiple comparisons, selection bias, and expected value traps that regularly fool judges, journalists, scientists, and executives.

advanced20 minProbability & Statistics
Question 1 of 617% Complete

A kidney stone treatment study finds: Treatment A is more effective than Treatment B for large stones (93% vs. 87%), AND Treatment A is more effective for small stones (87% vs. 83%). But when all patients are combined, Treatment B appears more effective overall (83% vs. 78%). The hospital board, looking only at the combined data, chooses Treatment B for all patients. What went wrong?