Chi-Square Goodness of Fit Test

χ2 = Σ(observed-expected)2/expected

  • Generally, large values of χ2 are improbable when the null hypothesis is true, but it could also happen because of the variability

  • If the calculated χ2 value is greater than the critical value, then the null hypothesis is rejected

  • To get df, take the amount of things you’re comparing and subtract 1, then use the chart