A chi-square (χ2) statistic is a test that is used to measure how expectations compare to actual observed data or model results.

The frequency tables list the variable values (hair color) in the order in which they appear in the data set. The "Test Percent" column lists the hypothesized percentages for the chi-square test.

The chi-square goodness-of-fit test examines whether the children's hair color has a specified multinomial distribution for two regions. The hypothesized distribution for hair color is 30 percent fair ...

In many biological problems, the experimenter may prefer to use a chi-square test for linear trends in proportions rather than the standard chi-square test of homogeneity. In this paper the ...