Chapter 11: Designs with 2+ IV Levels & Inferential Statistics

Question 1

What is the statistical test used for two or more levels of an independent variable as well as more than one IV?

Answer 1

The f-test which is computed via an ANOVA (analysis of variance)

Question 2

When can you use a t-test?

Answer 2

Only when analyzing the statistical significance of the difference between the means of two treatment conditions/only one IV manipulated at 2 levels

Question 3

What does it mean to have a significant f-value?

Answer 3

The variance among the treatment conditions is greater than the variance within the treatment conditions

Question 4

How is an f-test determined to be significant?

Answer 4

By comparing the computed/obtained value of F and the appropriate critical value of F/based on the chosen alpha level usually .05 and degrees of freedom

Question 5

Can a statistically significant f-value indicate that all differences among the treatment conditions are statistically significant?

Answer 5

No, a statistically significant f-value only indicates statistical significance somewhere. Must run either ANOVA or t-tests to determine what exactly is statistically significant.