In the Contingency platform, the Tests report shows the results for two tests that can be used to evaluate whether the response level rates are independent of the levels of the X variable.
The Tests report contains the following statistics:
N
The total number of observations.
DF
The degrees of freedom associated with the tests. The degrees of freedom are equal to (c - 1)(r - 1), where c is the number of columns and r is the number of rows.
-LogLike
The negative log-likelihood, which measures fit and uncertainty (much like sums of squares in continuous response situations). See “Likelihood, AICc, and BIC” in Fitting Linear Models.
Rsquare (U)
The portion of the total uncertainty attributed to the model fit.
– An R2 of 1 means that the levels of the X variable completely predict the levels of the Y variable.
– An R2 of 0 means that the model predicts no better than using fixed background response rates.
Test
The names of the chi-square tests of the hypothesis that the response rates are the same in each sample category.
ChiSquare
The test statistic for the chi-square test.
Prob>ChiSq
The probability of obtaining a chi-square value greater than the one computed if no relationship exists between the response and factor. If both variables have only two levels, Fisher’s exact probabilities for the one-tailed tests and the two-tailed test also appear.
For more information about the statistics in this report, see Statistical Details for the Tests Report.
This report gives the results of Fisher’s exact test for a 2 x 2 table. The results appear automatically for 2 x 2 tables. For more information about Fisher’s exact test and the test for r x c tables, see Fisher’s Exact Test Report.