Post-Hoc Test Examples

Statistics · Axiom Academy

EXAMPLE Post-Hoc Test Examples Comparing groups after a significant ANOVA using Tukey's HSD and Bonferroni correction Comparing all pairwise differences with Tukey's Honestly Significant Difference test Example 2: Bonferroni Correction Adjusting significance level for multiple pairwise t-tests Scenario: Effect of Study Methods on Test Scores A researcher tested three different study methods (Visual, Auditory, Kinesthetic) with different students. ANOVA showed a significant difference: F(2, 27) = 8.45, p = 0.001 . Now we need to determine which groups differ. Kinesthetic method (M = 92.8) significantly outperformed Visual method (M = 85.2) Kinesthetic method (M = 92.8) significantly outperformed Auditory method (M = 78.5) Visual and Auditory methods did not differ significantly Scenario: Drug Treatments for Blood Pressure Reduction Four drug treatments were compared for reducing blood pressure. ANOVA showed a significant effect: F(3, 36) = 6.82, p = 0.001 . We'll use pairwise t-tests with Bonferroni correction. Drug C (M = 18.6 mmHg) significantly more effective than Drug A (M = 12.4 mmHg) Drug C (M = 18.6 mmHg) significantly more effective than Drug D (M = 13.2 mmHg) A vs B comparison (p = 0.027) would be significant at α = 0.05 but not after correction Drug C shows superior blood pressure reduction overall Excellent work! You've completed both post-hoc test examples. Here's what we learned:

This is the written version of the interactive lesson above. See the full Statistics course.