In an effort to promote a new product, a marketing firm asksparticipants to rate the effectiveness of ads that varied by length(short, long) and by type of technology (static, dynamic,interactive). Higher ratings indicated greater effectiveness.
| Source of Variation | SS | df | MS | F |
|---|
| Length | 5 | | | |
| Technology | | | | |
| Length ×Technology | 142 | | | |
| Error | 570 | 114 | | |
| Total | 847 | | | |
(a) Complete the F-table and make a decision to retainor reject the null hypothesis for each hypothesis test. (Assumeexperimentwise alpha equal to 0.05.)
Source of
Variation | SS | df | MS | F |
|---|
| Length | 5 | | | |
| Technology | | | | |
Length×
Technology | 142 | | | |
| Error | 570 | 114 | | |
| Total | 847 | | | |
State the decision for the main effect of length.
Retain the null hypothesis.Reject the nullhypothesis.
State the decision for the main effect of technology.
Retain the null hypothesis.Reject the nullhypothesis.
State the decision for the interaction effect.
Retain the null hypothesis.Reject the nullhypothesis.
(b) Based on the results you obtained, what is the next step?
No further analysis is needed, because none of the effects aresignificant.Compute pairwise comparisons for the technologyfactor. Compute simple maineffect tests for the significant interaction.Compute pairwisecomparisons for the length factor.
