In: Statistics and Probability
The One-Way ANOVA applet lets you see how the F statistic and the P-value depend on the variability of the data within groups, the sample size, and the differences among the means.
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.
Ad source | n | x | s |
---|---|---|---|
Wall Street Journal | 66 | 4.77 | 1.50 |
National Enquirer | 61 | 2.43 | 1. |
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.