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Mathematics

Categorical Data Analysis Using the Chi-Squared Test

Quick fact

The chi-squared test was developed by Karl Pearson in 1900, and it is one of the most widely used statistical tests in research, appearing in fields from genetics to marketing.

Why this is interesting

If you flip a coin 100 times and get 60 heads, is the coin fair? Or imagine a survey shows men and women have different pet preferences—is that difference real or just by chance?