Imagine that you have performed a “beer goggling” experiment and have randomly a
ID: 3375180 • Letter: I
Question
Imagine that you have performed a “beer goggling” experiment and have randomly assigned 21 participants to drink either 0, 1, or 3 beers, and then had all participants rate the attractiveness of the same fellow college student on a scale from 0 to 50, with higher scores indicating greater perceived attractiveness. Here is the ANOVA source table and the group means. Use this information to answer the following questions.
Table: Beer and Attractiveness
Source
SS
df
MS
F
Between
720.096
2
360.048
21.54
Within
300.857
18
16.714
Total
1020.950
20
Table: Beer and Attractiveness, Group Means
Group
M
0 beer
21.5714
1 beer
26.5714
2 beers
35.7143
I got HSD value as 5.58, 0.71 large effect size, 3.57 critical f value. Based on the information what would you conclude?
A. Participants who drank three beers rated the attractiveness of the fellow college student significantly higher, on average, than participants who drank no beer.
B. Participants who drank three beers rated the attractiveness of the fellow college student significantly higher, on average, than participants who drank no beer and participants who drank one beer.
C. Participants who drank three beers rated the attractiveness of the fellow college students significantly higher, on average, than participants who drank no beer and participants who drank one beer. Also, participants who drank one beer rated the attractiveness of the fellow college student significantly higher, on average, than participants who drank no beer.
I believe it is B, as ..
xbar1-xbar2 (Means of groups)=-5
xbar1-xbar3=-14.14
xbar2-xbar3=-9.13
So it seems there was no significant difference between xbar1-xbar3 or xbar2-xbar3 or am I wrong? Thank you so much I am confused and may not have got the right answers for calculating HSD. I thought my HSD value is correct
Source
SS
df
MS
F
Between
720.096
2
360.048
21.54
Within
300.857
18
16.714
Total
1020.950
20
Explanation / Answer
Here as we got the HSD value = 5.58
so as you have written
xbar1-xbar2 (Means of groups)= -5
xbar1-xbar3=-14.14
xbar2-xbar3=-9.13
so for group 1 and group 3 the absolute value is less than HSD. so here these two grpups are not different from each other.
Here that means option B is correct as group 3 is significantly different than grorp 1 and group 2.