Stats16 Essay Example | Topics and Well Written Essays - 1250 words

Stats16 - Essay Example Answer True False   Question 5    If other factors are held constant, then increasing the sample standard deviation will increase the likelihood of rejecting the null hypothesis. Answer True False   Question 6    If all other factors are held constant, increasing the sample size from n = 25 to n = 100 will increase the power of a statistical test. Answer True False   Question 7    By selecting a smaller alpha level, a researcher is ___. Answer a. attempting to make it easier to reject H 0 b. better able to detect a treatment effect c. reducing the risk of a Type I error d. All of the above.   Question 8    The critical boundaries for a hypothesis test are z = +1.96 and -1.96. If the z-score for the sample data is z = -1.90, then what is the correct statistical decision? Answer a. Fail to reject H 1. b. Fail to reject H 0. c. Reject H 1. d. Reject H 0.   Question 9    Increasing the alpha level (for example, from ? = .01 to ? = .05) ____. Answer a. increases the pr obability of a Type I error b. increases the size of the critical region c. increases the probability that the sample will fall into the critical region d. All of the above    Question 10    In a hypothesis test, an extreme z-score value, like z = +3 or z = +4, ____. Answer a. is probably in the critical region b. means that you should probably reject the null hypothesis c. ... concluded that a treatment has no effect when it really does d. concluded that a treatment has an effect when it really has no effect   Question 12    A Type I error means that a researcher has ____. Answer a. concluded that a treatment has an effect when it really does b. concluded that a treatment has no effect when it really has no effect c. concluded that a treatment has no effect when it really does d. concluded that a treatment has an effect when it really has no effect   Question 13    A researcher risks a Type I error ____. Answer a. anytime H 0 is rejected b. anytime H 1 is rejected c. anytime the decision is "fail to reject H 0" d. All of the other options are correct.    Question 14    A researcher conducts a hypothesis test to evaluate the effect of a treatment. The hypothesis test produces a z-score of z = ?2.60. Assuming that the researcher is using a two-tailed test, what is the correct statistical decision? Answer a. Reject the null hypothesis with ? = .05 but not with ? = .01. b. Reject the null hypothesis with either ? = .05 or ? = .01. c. Fail to reject the null hypothesis with either ? = .05 or ? = .01. d. cannot answer without additional information   Question 15    A researcher uses a hypothesis test to evaluate H 0 ? = 80. Which combination of factors is most likely to result in rejecting the null hypothesis? Answer a. M = 85 and ? = 10 b. M = 85 and ? = 20 c. M = 90 and ? = 10 d. M = 90 and ? = 20   Question 16    A researcher uses a hypothesis test to evaluate H 0 ? = 80. Which combination of factors is most likely to result in rejecting the null hypothesis? Answer a. M = 85 and n = 10 b. M = 85 and n = 20 c. M = 90 and n = 10 d. M = 90 and n = 20   Question 17    A researcher uses a hypothesis test to evaluate H 0 ?= 80. Which