7. A new company has made the claim that its test preparation program will improve SAT scores by 50 points. Assume the population mean for SAT scores is 500 with a standard deviation of 100. What is the predicted effect size for an increase of 50 points (predicted mean of research population is 550)? Choose the closest: A) -.5 B) 0 C) .2 D) .5 E) .8

16. When going from an (or significance level) of 5% to a new one of 1%: A) the probability of committing a Type I error will be greater B) the power of the test will be lower C) will be decreased D) there is greater likelihood of claiming that is false when it is really true

17. The term "decision errors" refer to the fact that we employ the scientific method to come to a conclusion that is ______________ . A) not based on reason or logic. B) always correct. C) usually based on faulty data. D) only an educated, best bet as to the state of reality.

18. Keeping in mind that alpha is generally set very low or strict (so to speak), which is generally considered to be the worst situation from a scientific viewpoint? A) Failing to reject a true null B) Rejecting a true null C) Rejecting a false null D) Failing to reject a false null

19. Changing the significance level cutoff (alpha) to 10% instead of the more usual 5% would increase the likelihood of A) a Type I error. C) failing to reject the null hypothesis. B) a Type II error. D) both A and B.

20. A social psychologist who is designing a study to see whether people who see a particular film are more likely to use violence as a solution to a problem plans to use a scale that assesses this construct and has a population mean of 78 with a standard deviation of 14. The psychologist expects an increase of 8 points above the population mean (the predicted mean of the research population is 86). Which of the following is closest to the expected effect size? A) -1 D) .5 B) -.5 E) 1 C) 0

21. A standardized effect size is concerned with: A) the proportion of change in scores that we can be sure is due to the effect of the treatment B) the degree to which the two populations overlap or do not overlap C) the proportion of change in scores that is due to chance D) the distance between the mean of the original population and the new one 22. The unit of measure for a standardized effect size is: A) standard errors of the mean B) units of power C) standard deviations D) the square root of sample size 23. Which of the following would increase power? A) decreasing the difference between the means of the two populations B) using a smaller sample C) using a one-tailed test where the correct tail is chosen D) using populations that have greater variability in scores 24. In actual practice, the usual reason for considering power before conducting a study is: A) to eliminate the possibility that a mistake may occur. B) to ensure that regardless of whether the research hypothesis is true, the experiment will yield a significant result. C) to determine the number of participants needed to have the desired level of power. D) to anticipate the likelihood that the experiment will need to be repeated