Short version - I have run some non-parametric tests (Friedman) as sort of backup to a ANOVA because of an assumption violation - should I report the pairwise comparisons for these tests in addition to planned comparisons I did following the ANOVA?
TIA, E
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Longer version - I have run a 2 (groups) x 3 (conditions) mixed repeated measures anova on response time data. For one of the groups, all three conditions distributions violated the assumption of normality, so I ran a couple Freidman tests (one for each group). The ANOVA showed a main effect of condition, and an interaction between group and condition (the main effect of group was not significant). planned comparisons showed that both groups scored significantly higher in Condition A than B, but only one group scored significantly higher in Condition C compared to B. Beyond finding that the Freidman tests revealed significant effects of Condition for both groups, should I report the pairwise comparisons which SPSS provides with the Friedman results as well? To say whether they corroborate the planned comparisons done following the ANOVA?
Does main test affect the outcome of the follow ups, or is, for example, a pairwise comparison a pairwise comparison no matter whether it follows an ANOVA or a Friedman test, so long as the data are the same?
Many thanks in advance,
E
TIA, E
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Longer version - I have run a 2 (groups) x 3 (conditions) mixed repeated measures anova on response time data. For one of the groups, all three conditions distributions violated the assumption of normality, so I ran a couple Freidman tests (one for each group). The ANOVA showed a main effect of condition, and an interaction between group and condition (the main effect of group was not significant). planned comparisons showed that both groups scored significantly higher in Condition A than B, but only one group scored significantly higher in Condition C compared to B. Beyond finding that the Freidman tests revealed significant effects of Condition for both groups, should I report the pairwise comparisons which SPSS provides with the Friedman results as well? To say whether they corroborate the planned comparisons done following the ANOVA?
Does main test affect the outcome of the follow ups, or is, for example, a pairwise comparison a pairwise comparison no matter whether it follows an ANOVA or a Friedman test, so long as the data are the same?
Many thanks in advance,
E