What is the chi ... formula, the ∑ symbol denotes taking the sum of (adding together) the succeeding quantities over all four cells in the contingency table. For our example: This gives us a test ...

Paige McLaughlin / Investopedia Chi-square is a statistical measurement ... students select among the offered classes using the formula given above and a χ 2 statistical table.

Degrees of freedom allow data points in a sample to be randomly selected except for the final value. Degrees of freedom ... the importance of a chi-square statistic and the validity of the null ...

A statistical test that allows one to determine whether observed quantities of a specific characteristic differed from the expected value purely by chance.