The hypothesis the statistician wants to test is: A. H?:µ=75 vs. H?:µ=78 B. H?:µ=75 vs. H?:µ>78 C. H?:µ=75 vs. H?:µ>75 D. H?:µ=75 vs. H?:µ<75 Q13. Suppose we are testing the null hypothesis H0:µ=20 and the alternative Ha:µ?20 , for a Normal population with ?=5 . A random sample of 25 observations is drawn from the population, and we find that the sample mean of these observations is x? =17.6 . The P-value is closest to: A. 0.0668. B. 0.0082. C. 0.0164. D. 0.1336. Q14. The P-value of the test of the null hypothesis is: A. the probability, assuming the null hypothesis is true, that the test statistic will take a value at least as extreme as that actually observed. B. the probability, assuming the null hypothesis is false, that the test statistic will take a value at least as extreme as that actually observed. C. the probability the null hypothesis is true. D. the probability the null hypothesis is false. Q15. The Survey of Study Habits and Attitudes (SSHA) is a psychological test that measures the motivation, attitudes, and study habits of college students. Scores range from 0 to 200 and follow, approximately, a Normal distribution, with mean of 110 and standard deviation ?=20 . You suspect that incoming freshman have a mean µ that is different from 110, because they are often excited yet anxious about entering college. To verify your suspicion, you test the hypotheses H?:µ=110 , H?:µ?110 . You give the SSHA to 50 students who are incoming freshman and find their mean score. If you observe a sample mean of x? =115.35, what is the corresponding P-value? A. 0.058 B. 0.029 C. 0.0787. D. None of the answer options are correct
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