What conclusion can you draw from the results of the paired t-test?Question 20Answera.People responding are more educated than their fathers on average, and this difference is significantb.People responding are more educated than their fathers on average, but this difference is not significantc.People responding are less educated than their fathers on average, and this difference is significantd.People responding are less educated than their fathers on average, but this difference is not significant

In which of the following situations would it be appropriate to use a paired t-test to analyze the data? Check all that apply. A researcher was interested in the differences in attitudes towards saving money and eliminating debt between couples who are engaged to be married. As part of a premarital counseling program, 45 engaged couples filled out a survey that assessed their attitudes towards financial matters such as their priorities for saving money and eliminating debt. The researcher compared the scores of each member of the engaged couple to see if there was a mean difference in the couples’ attitudes towards saving money and eliminating debt. A biologist was interested in finding out whether rats who are littermates (siblings who are born at the same time) have similar abilities when learning how to run a maze. The biologists selected 50 pairs of littermates and tested how many trials it took for the rat to get to the end of the maze in less than 10 seconds. The null hypothesis was that there would be no mean difference in the number of trials that the rat and their litter mate would take to complete the maze in under 10 seconds. Each rat’s maze time was compared to his/her littermate. A medical researcher believes that a new drug will increase a patient’s red blood cell count at a higher rate than that achieved by an old drug currently in use. The researcher randomly assigns 50 patients to be in the “new drug” group and 50 patients to be in the “old drug” group, then compares the mean red blood cell count for the “new drug” group to the red blood cell count of the “old drug” group. A researcher is interested in determining the effects of caffeine on manual dexterity. The researcher recruits a sample of 60 participants and asks each participant to complete a manual dexterity task similar to the game “Operation.” Each participant completes the task twice: On Day 1, participants complete the task when they have not consumed any caffeine for at least 6 hours. On Day 2, the participants drink a beverage with 200 mg of caffeine 20 minutes before completing the task. The researcher compares each individual’s number of errors in the task with and without caffeine exposure and computes a mean difference.

The paired t-test is essentially ...Question 2Answera.A two-sample t-test with the null hypothesis that the two means are differentb.A two-sample t-test with the null hypothesis that the two means are equalc.A one-sample t-test with the null hypothesis that the difference scores have a mean equal to the higher scored.A one-sample t-test with the null hypothesis that the difference scores have a mean of 0

In which of the following situations would it be appropriate to use a paired t-test to analyze the data? Check all that apply. A marriage therapist believes that many couples have different perspectives regarding the state of their marriage prior to the start of couples therapy. In order to determine whether there is difference in marital satisfaction, prior to the start of couples therapy, each member of 30 married couples is individually given a marital satisfaction questionnaire. For each couple, the marital satisfaction scores of the wife and husband are compared to see if there is a difference in how they view the state of their marriage. A psychologist was interested in determining whether fraternal twins differ in terms the degree to which they are extroverts. A sample of 50 fraternal twins was given the Eysenck personality questionnaire to assess their levels of extraversion. Each twin’s extraversion score was compared to his/her fraternal twin. A psychiatrist believes that a new medication (New Drug) is more effective at reducing the symptoms of depression than a placebo, sugar pill (Placebo). Sixty people with depression were randomly assigned to one of two groups, (1) New Drug or (2) Placebo, and were given the assigned drug or sugar pill for 30 days. Each of the 60 participants then completed the Beck Depression Inventory and the mean depression score for the New Drug group is compared to the mean depression score for the Placebo group. A researcher is interested in determining the effects of sleep deprivation on the accuracy with which mazes are completed. Thirty people are given a test of mazes on Day 1 at 9 am and again on Day 2 at 9 pm after being kept awake for 36 hours. The researcher then compares the number of errors made on Day 1 to Day 2.

If paired scores are correlated highly (say, at r = .75) this means, compared to scores correlated weakly (say at r = .10), then the strongly correlated pairs ...Question 3Answera.... should not be used in a paired t-testb.... should each be tested for difference from zeroc.... will have more power in a paired t-testd.... should be added, rather than subtracted from each other

Suppose a marriage counselor wants to investigate how regional background of a spouse affects marital success. He randomly assigns a participant into two groups where group A constitute marriage partner from the same region of the country and group B comprises of those whose marriage partners are from different regions. Ratings of the success of the marriage, the higher the rating, the better the marriage. The following data were observed for group A; 10 9 8 8 9 10 9 8 7 8 for group B; 6 7 8 8 7 7 6 5 8 6 Use T-test to answer the above question