ANOVA, One-factor independent measures ANOVA, Post-hoc, Planned Comparisons

Question 1

What is ANOVA?

Answer 1

ANOVA (Analysis of Variance) is a statistical test used to compare the means of three or more groups.

Question 2

What is a one-way independent measures ANOVA?

Answer 2

A one-way independent measures ANOVA compares the means of three or more independent groups on one factor.

Question 3

What is the F-ratio in ANOVA?

Answer 3

The F-ratio compares between-group variance to within-group variance. A higher F-ratio suggests significant differences between groups.

Question 4

When is a one-way ANOVA appropriate?

Answer 4

Use a one-way ANOVA when comparing the means of three or more independent groups on one factor.

Question 5

What are post-hoc tests?

Answer 5

Post-hoc tests are performed after ANOVA to determine which specific group means differ from each other, controlling for Type I error.

Question 6

What is Tukey’s HSD test?

Answer 6

Tukey’s HSD (Honestly Significant Difference) test is a post-hoc test used to make pairwise comparisons between group means.

Question 7

What are planned comparisons?

Answer 7

Planned comparisons (also called contrasts) are specific hypotheses developed before data collection that test differences between certain groups.

Question 8

How are contrast weights used in planned comparisons?

Answer 8

Contrast weights assign values to group means based on their hypothesized relationships, helping focus the comparison on specific groups.

Question 9

How do you interpret the results of a planned comparison?

Answer 9

If the p-value is less than 0.05, the planned comparison indicates that the group difference tested is statistically significant.