Following a recent congressional election, a political scientist attempted to investigate the relationship between campaign expenditures on television advertisements and subsequent voter turnout. The following table presents the percentage of total campaign expenditures delegated to television advertisements (TVEXP) and the percentage of registered voter turnout (VOTE) for a hypothetical sample of 20 congressional districts.
a. Determine the least-squares line of VOTE on TVEXP, and draw the estimated line on the accompanying scatter diagram.
b. Are any of the assumptions for straight-line regression clearly not satisfied in this example?
c. Test the null hypothesis that the true slope is 0; be sure to interpret your result.
d. Test the hypothesis µy|x0 = 45 for X0 = = 36.99. Interpret your result.
e. Calculate the corresponding 95% confidence interval for µy|36.99, and interpret your result.

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VOTE TVEXP VOTE TVEXP (Y) α) r) (x) 35.4 28.5 58.2 48.3 46. 40.2 45.5 64.8 50. 52.0 37.927.2 48.2 37.8 40.8 31.3 61.9 50.1 36.5 31.3 32.724.8 53.842.2 24.6 23.0 31.2 42.6 365 49.6 40.2 56.6 46.1 34.8 44.0 30.1 41.8 54.0 27.2 46.1 701 60 50 40 30 20 10 0 10 20 304050 60 TVEXP (x)