1 During an election, an exit poll is taken on 400 randomly selected voters and 214 of those polled voted for Candidate \"Jim\". A majority is needed to win the election. We want to see if we can conclude that the majority (more than 50%) will vote for Candidate \"Jim\" based on our sample proportion from the exit poll. In this scenario, the null hypothesis is that____ the population proportion of those voting for Candidate \"Jim\" is greater than .50 (50%) the population proportion of those voting for Candidate \"Jim\" is equal to .50 (50%) Question 2 We are testing to see if a new drug is more effective in treating high blood pressure than the most commonly used drug. The drug used most often is known to control blood pressure in 75% of patients using it. The null hypothesis is that the new drug will control blood pressure in 75% of patients using it (the same as the most commonly used drug). The alternative hypothesis is that the new drug will control blood pressure in more than 75% of patients using it. We would make a Type 2 Error if: We conclude that the new drug controls blood pressure in 75% of patients using it when actually the new drug controls blood pressure in more than 75% of patients using it. We conclude that the new drug controls blood pressure in 75% of patients using it when actually the new drug controls blood pressure in 75% of patients using it. We conclude that the new drug controls blood pressure in more than 75% of patients using it when actually the new drug controls blood pressure in more than 75% of the patients using it We conclude that the new drug controls blood pressure in more than 75% of the patients using it when actually the new drug controls blood pressure in 75% of patients using it. Question 3 Two randomly selected groups of 200 students each were taught two different memorization methods over a four week period. At the end of four weeks a memorization test with a maximum possible score of 100 was given. The confidence interval of the difference in the two group population mean scores on the memorization test was (0.8 to 1.4). What statement best reflects the results of this study. the results are not statistically significant, but are of practical significance the results are statistically significant, but probably not of practical significance since the true population mean difference is a very small percentage of the total points possible (difference in points is 0.8% to 1.4% of the total points possible) the results are statistically significant and also of practical significance since the true population mean difference in points is % of the total points possible. the results are not statistically significant and also not of practical significance Question 4 In which situation is a hypothesis test most likely to end with a significant result? 15 subjects in each comparison group and a very effective treatment. 80 subjects in each comparison group and a very effective treatment. 15 subjects in each group and a barely effective treatment. 80 subjects in each group and a barely effective treatment. Question 5 In which situation is a hypothesis test most likely to end without a significant result? 15 subjects in each comparison group and a very effective treatment 80 subjects in each comparison group and a very effective treatment 15 subjects in each group and a barely effective treatment 80 subjects in each group and a barely effective treatment Question 6 A study asked 500 men who had prostate cancer about their consumption of 50 different foods. One of the foods is found to have a statistically significant relationship to prostate cancer. The most likely reason for this is___ That the food definitely has a relationship to prostate cancer You would expect to see one significant result when you carry out 50 significance tests. Statistical significance does not imply practical significance There is a third confounding variable contributing to the results Question 7 Our hypothesis test is testing to see if there is a difference in the population mean between two groups. The data for each group has considerable variability. Given that there is considerable variability in the data for the two groups __________. it will be easy to reject the null hypothesis of \"no difference\" with a small sample it will be likely we don't reject the null hypothesis of \"no difference\" with a small sample Question 8 We test whether two group population means differ. The p-value of our test statistic is 0.047 which is less than or equal to 0.05. What is the most appropriate conclusion we can make with the information given? We can conclude that the difference in the two group population means is both statistically significant and practically significant. We can conclude that the difference in the two group population means is neither statistically significant nor practically significant. We can conclude that the difference in the two group population means is statistically significant, but we cannot assess whether the difference is practically significant until we are given a confidence interval for the difference in the two group population means. Question 9 Which of the following two statements are correct? A statistically significant result is always practically significant A result that is not statistically significant is never of practical significance It is possible that a statistically significant result is not of practical significance It is possible that a result that is not statistically significant is of practical significance. Question 10 A hypothesis test with a statistically significant result indicates that the alternative hypothesis is correct. True False Question 11 Researchers must obtain Informed Consent from all human participants in a research study. Informed Consent requires that participants are informed of the following (check all that apply): Informed consent must describe the research and what is requested of the subjects Informed consent must describe the anticipated risks and potential benefits Informed consent must disclose any alternative procedures or courses of treatment (other than participation in the study), if any, that may be advantageous to the subject. Informed consent must describe provisions maintaining the subject's privacy and confidentiality of records Informed consent must indicate that a subject has the right to leave the study at any time without penalty or loss of benefits, (benefits to which the subject is otherwise entitled to just by agreeing to participate). Question 12 Large payments to subjects for taking part in an experiment are unethical primarily because: It is a form of coercion that reduces the freedom of choice about taking part. It may cause the subject to give fake results so they can participate in other experiments If this was a precedent, it would make experiments too expensive Question 13 In testing whether a new cold remedy reduces the average length of time that a subjects cold would last, a researcher plans an experiment with 25 subjects getting the new remedy and 25 getting a placebo. It is more likely that the researcher can get a small p-value if she used fewer subjects it is more likely that the researcher can get a small p-value if she used more subjects It is more likely that the researcher can get a larger p-value by using a within subject design with less variability