Dunnett’s Pairwise Multiple Comparison
The test statistic is:
- and are the means of the two groups being compared and is the mean of the of groups,
- when applying the test to Repeated Measures, each respondent’s average is initially subtracted from their data and it is this corrected data that constitutes of ,
- is the number of observations in the th of groups,
- is the Calibrated Weight for the th observation in the group,
- is the Effective Sample Size for the group,
- for Repeated Measures and otherwise.
- is evaluated using a multivariate distribution (see Dunnett C. W. (1955.) "A multiple comparison procedure for comparing several treatments with a control", Journal of the American Statistical Association, 50:1096–1121).
Circumstances when this test is applied
- Computing either:
- This test has been selected in the Statistical Assumptions setting of Multiple comparison correction > Column comparisons