Corporate advertising tries to enhance the image of the corp
Corporate advertising tries to enhance the image of the corporation. A study compared two ads from two sources, the Wall Street Journal and the National Enquirer. Subjects were asked to pretend that their company was considering a major investment in Performax, the fictitious sportswear firm in the ads. Each subject was asked to respond to the question \"How trustworthy was the source in the sportswear company ad for Performax?\" on a 7-point scale. Higher values indicated more trustworthiness. Here is a summary of the results.
Find the two-sample pooled t statistic. Then formulate the problem as an ANOVA and report the results of this analysis. Verify that F = t 2.
| Ad source | n | x | s | 
|---|---|---|---|
| Wall Street Journal | 66 | 4.77 | 1.50 | 
| National Enquirer | 61 | 2.43 | 1.64 | 
Solution
H0: mu1 = mu2
Ha: mu1 not equals mu2
(Two tailed test for comparison of means)
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df = 125
   standard error of difference = 2.218
Hence t statistics = mean difference/std error = 2.3400/2,218 =
1.0549
The two-tailed P value equals 0.2935
As p > 0.05, accept null hypothesis.
The two means would be equal.
Anova table would be as follows:
As p value is negligible, reject null hypothesis.
Two means are not equal.
| Group | Group One | Group Two | 
|---|---|---|
| Mean | 4.7700 | 2.4300 | 
| SD | 12.1861 | 12.8088 | 
| SEM | 1.5000 | 1.6400 | 
| N | 66 | 61 | 

