Sometimes a drug that cures a disease turns out to havea nasty side effect. For example, some antidepressantdrugs may cause suicidal thoughts in younger patients.A researcher conducts a study of such a drug to look forevidence of such side effects. He tests the hypothesis thatthere’s no side effect at the 0.05 significance level and finds a P-value of 0.03. Which of the following state-ments is true? A) He could have committed a Type I error by concludingthere’s no such side effect if, in fact, there really is.B) He could have committed a Type II error byconcluding there’s no such side effect if, in fact,there really is.C) He could have committed a Type I error byconcluding there is such a side effect if, in fact,there really isn’t.D) He could have committed a Type II error byconcluding there is such a side effect if, in fact,there really isn’t.E) With a P-value as low as 0.03 he could not havecommitted either type of error.

Are freshmen psychology majors just as likely to change their major before they graduate compared to freshmen business majors? 366 of the 673 freshmen psychology majors from a recent study changed their major before they graduated and 394 of the 705 freshmen business majors changed their major before they graduated. What can be concluded at the a = 0.10 level of significance? For this study, we should use z-test for the difference between two population proportions a. The null and alternative hypotheses would be: Ho: p1 p2 v (please enter a decimal) H1: p1 p2 (Please enter a decimal) b. The test statistic z v -0.508 X (please show your answer to 3 decimal places.) c. The p-value = 0.6115 X (Please show your answer to 4 decimal places.) d. The p-value is > vV a e. Based on this, we should fail to reject the null hypothesis. f. Thus, the final conclusion is that ... O The results are statistically significant at a = 0.10, so there is sufficient evidence to conclude that the proportion of…

Researchers investigate how the presence of cell phones influence the quality of human interaction.  Subjects are randomly selected from a population and divided into an experimental group that is asked to leave their phones in the front of the room and a control group that are not asked to leave their cell phones at the front of the room.  Subjects are left alone for 10 minutes and then asked to take a survey designed to measure quality of interactions they had with others in the experiment.  What statistical test is appropriate?

If a hypothesis is rejected at significance level α = 0.01, is it possible that the hypothesis is not rejected if the same test was done at significance level α = 0.05 (with everything else staying the same)?