In: Math
It might be predicted that consumer buying behavior would vary
with the location of products in a store. Therefore, a team of
market researchers looked at the sales per day for a well-known and
unknown brand of candy bars. Additionally, the researchers placed
the candy bars in the usual location and next to the cash register
in different stores. What can the market researchers conclude with
an α of 0.05?
known brand/ usual |
known brand/ cash register |
unknown brand/ usual |
unknown brand/ cash register |
---|---|---|---|
16 24 19 17 26 30 18 |
25 15 16 20 31 27 19 |
11 6 9 13 14 7 11 |
19 18 16 21 22 17 19 |
a) Compute the appropriate test statistic(s) to
make a decision about H0.
Location: critical value = ; test
statistic =
Brand: critical value = ; test
statistic =
Decision: ---Select--- Reject H0 Fail to reject H0
Interaction: critical value = ; test
statistic =
Decision: ---Select--- Reject H0 Fail to reject H0
b) Compute the corresponding effect size(s) and
indicate magnitude(s).
Location: η2
= ; ---Select--- na trivial effect small
effect medium effect large effect
Brand: η2
= ; ---Select--- na trivial effect small
effect medium effect large effect
Interaction: η2
= ; ---Select--- na trivial effect small
effect medium effect large effect
c) Make an interpretation based on the
results.
There is a location difference on candy bar sales.There is no location difference on candy bar sales.
There is a brand difference on candy bar sales.There is no brand difference on candy bar sales.
There is a location by brand interaction on candy bar sales.There is no location by brand interaction on candy bar sales.
a)
data
known brand | unknown brand | ||
usual | 16 | 11 | |
24 | 6 | ||
19 | 9 | ||
17 | 13 | ||
26 | 14 | ||
30 | 7 | ||
18 | 11 | ||
cash register | 25 | 19 | |
15 | 18 | ||
16 | 16 | ||
20 | 21 | ||
31 | 22 | ||
27 | 17 | ||
19 | 19 | ||
result
Anova: Two-Factor With Replication | ||||||
SUMMARY | known brand | unknown brand | Total | |||
usual | ||||||
Count | 7 | 7 | 14 | |||
Sum | 150 | 71 | 221 | |||
Average | 21.42857 | 10.14286 | 15.78571 | |||
Variance | 27.95238 | 8.809524 | 51.25824 | |||
cash register | ||||||
Count | 7 | 7 | 14 | |||
Sum | 153 | 132 | 285 | |||
Average | 21.85714 | 18.85714 | 20.35714 | |||
Variance | 35.47619 | 4.47619 | 20.86264 | |||
Total | ||||||
Count | 14 | 14 | ||||
Sum | 303 | 203 | ||||
Average | 21.64286 | 14.5 | ||||
Variance | 29.32418 | 26.57692 | ||||
ANOVA | ||||||
Source of Variation | SS | df | MS | F | P-value | F crit |
Sample | 146.2857 | 1 | 146.2857 | 7.627561 | 0.010848 | 4.259677 |
Columns | 357.1429 | 1 | 357.1429 | 18.62197 | 0.000237 | 4.259677 |
Interaction | 120.1429 | 1 | 120.1429 | 6.264432 | 0.019528 | 4.259677 |
Within | 460.2857 | 24 | 19.17857 | |||
Total | 1083.857 | 27 |
Compute the appropriate test statistic(s) to make a decision
about H0.
Location: critical value = 4.259677 ; test
statistic = 146.2857
Decision - reject Ho
Brand: critical value =4.259677 ;
test statistic =
357.1429 |
Decision: --Reject H0
Interaction: critical value =4.259677
; test statistic =
120.1429 |
Decision: -Reject H0