A sociologist wishes to test the hypothesis that executives at large companies are taller than the average population. The population distribution is assumed to be normal, and the standard deviation for male American executives is 3.1 inches. Suppose that a random sample of 15 male American executives has a mean of 70.5 inches. Test the hypothesis that the mean height of male American executives is above the average height of 69 inches for American men. (a) State the null hypothesis and alternative hypothesis. (b) Calculate the z-test statistic. (c) Calculate the P-value. (d) Is the result significant at the level α = 0.05? Why? (e) What would change if a two-sided alternative had been used?
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The null hypothesis (H0) is that the mean height of male American executives is equal to the average height of American men, which is 69 inches. The alternative hypothesis (H1) is that the mean height of male American executives is greater than the average height Show more…
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