An article in Fortune claimed that nearly one-half of allengineers continue academic studies beyond the B.S. degree,ultimately receiving either an M.S. or a Ph.D. degree. Datafrom an article in Engineering Horizons indicated that 117of 484 new engineering graduates were planning graduate study. a) Are the data from Engineering Horizons consistentwith the claim reported by Fortune? Use =0.05 in reaching your conclusions. Findthe P-value for this test. b) Discuss how you could have answered the question in part(a) by constructing a two-sided confidence interval onp. a) Are the data from Engineering Horizons consistentwith the claim reported by Fortune? Use =0.05 in reaching your conclusions. Findthe P-value for this test. b) Discuss how you could have answered the question in part(a) by constructing a two-sided confidence interval onp.
Explanation / Answer
Given phat=117/484=0.24 (a) The test hypothesis is Ho:p=0.33 Ha:p not equal 0.33 The test statistic is Z=(phat -p)/p*(1-p)/n =(0.24-0.33)/sqrt(0.33*(1-0.33)/484) = -4.21 The p-value is 2*P(Z 0.24 ± 1.96*sqrt(0.33*(1-0.33)/484) --> (0.1981, 0.2818)