Chi-square test Pearson's chi-square (χ 2 ) test is the best-known of several chi-square tests. It is mostly used to assess the tests of goodness of fit. - ppt download
Pearson's Chi-square tests - intuition and derivation | Personal blog of Boris Burkov
Alternative to Pearson's chi-square goodness of fit test, when expected counts < 5 - Cross Validated
Chi-Square Test | How to Calculate Chi-square using Formula with Example