Question

Researchers in mental health fields are often interested in evaluating the effectiveness of using food image to enhancne positive mood. Adapting a typical design from such studies, suppose e have participants rate their mood chane on a standard self report affect sclae after viewing images of ""comfort" foods, fruits/beggies/ (FV), and random non-food images (used as a control group) the reults are given in the able at the right for this hypothetical study

Images

Control F/V Comfort Foods

0 0 4

0 2 2

1 2 4

3 2 6

0 1 0

(a) complete the f table round to two decimals

Source of varitation ss df ms Fobt

beteen groups ___ ___ ___ ___

between persons _____ ____ __

within groups error ___ ___ ___

total ____ ___

(b) compute a bonfrerroni procedure and interpret the results. (assume experimentwise alpha equal to 0.05. Select all that apply)

___ Participants rated a significantly larger mood change after viewing images of fruits/vegetables compared with the mood change after vieing control images

___ There were no significant differences between any of the groups

___ Participants rated a significantly largermood change after vieing images of comfort foods compared with the mood change after viewing control images

___ Participants rated a significantly larger mood change after viewing images of comfort foods compared with the mood change after viewing images of fruits/vegitables

Answer 1

Applying within group ANOVA:

Source	SS	df	MS	F
treatments	15.60	2	7.80	5.32
Blocks	19.07	4	4.77	3.25
Error	11.73	8	1.47
Total	46.40	14

b)

Participants rated a significantly larger mood change after viewing images of comfort foods compared with the mood change after viewing control images