A researcher has been hired by a pizzeria to determine which type of crust customers prefer. The restaurant offers three types of crust: hand tossed, thick, and thin. Following are the mean number of 1-inch pieces of pizza eaten for each condition from 10 subjects who had the opportunity to eat as many pieces with each type of crust as they desired. The ANOVA summary table also follows:
Source df SS MS F
Subject 2.75
Between 180.05
Error 21.65
Total 204.45
Crust Type Mean n
Hand-tossed 2.73 10
Thick 4.20 10
Thin 8.50 10
a. Complete the ANOVA summary table.
b. Is F obt significant at = .05; at = .01?
c. Perform post hoc comparisons if necessary.
d. What conclusions can be drawn from the F-ratio and the post hoc comparisons?
e. What is the effect size, and what does this mean?
f. Graph the means.