Psy 210 Final Exam
Group 1 Mean 6.13 Estimated population variance of scores 9.27 Sample size 8 Group 2 Mean 22.17 Estimated population variance of scores 6.97 Sample Size 6 32. What is the research hypothesis for this study? a. µ1 ≠ µ2 b. µ1 > µ2 c. µ1 < µ2 d. µ1 ≥ µ2 e. µ1 ≤ µ2
a. µ1 ≠ µ2
Group 1 Mean 6.13 Estimated population variance of scores 9.27 Sample size 8 Group 2 Mean 22.17 Estimated population variance of scores 6.97 Sample Size 6 37. Estimated pooled population variance a. (7/12) 6.13 + (5/12) 6.13 b. (7/12) 9.27 + (5/12) 6.97 c. (8/14) 6.13 + (6/14) 6.13 d. (8/14) 9.27 + (6/14) 6.97
b. (7/12) 9.27 + (5/12) 6.97
10. A researcher wants to know if casino staff are more anxious than the general population of people. The average anxiety score in the normal population is 22. The population standard deviation is 3. The one casino staff member that he surveyed for his research had an anxiety score of 25.5. Using the .05 probability level, find out if casino staff members are significantly more likely to be more anxious than the general population. What is the mean of the treatment (experimental) distribution? a. 22 b. 25.5 c. 3 d. 5
b. 25.5
8. Bill wants to know if his posts are doing better on Youtube versus Facebook. He has information on the average number of "likes" scores and the standard deviation of "likes" scores of posts that are similar to his content, per day. For Facebook: Bill's score = 600. Mean likes of similar posts = 800; SD of likes of similar posts = 200. The percentage of people who have lower scores than Bill on Facebook is: a. 14% + 2% = 16% b. 34% + 14% + 2% = 50% c. 2% d. 34% + 34% = 68%
b. 34% + 14% + 2% = 50% ????????
23. If a research article presented the results of an analysis of variance as, "F (5, 64) = 3.60, p < .05," then how many groups were there in the study? a. 7 b. 6 c. 64 d. 63
b. 6
11. A manufacturer who is considering the implementation of a one-week training program for all new employees decides to test the program with the next 100 employees hired, and then compare their productivity rate to the productivity rate of new employees based on past records—a rate that is normally distributed with a mean of 60 and a standard deviation of 8. The new program needs to produce a minimum improvement of 4 to be considered worthwhile. What is the mean of the comparison distribution? a. 52 b. 60 c. 68 d. 100
b. 60
7. If an organizational psychologist conducts extensive interviews with 40 workers at a large factory to examine the morale among workers at that factory, the population is a. The 40 workers interviewed. b. All the workers in the factory except the 40 interviewed. c. All the workers in the factory. d. All the workers necessary to create a normal distribution. e. All workers who work in factories.
c. All the workers in the factory
Group 1 Mean 6.13 Estimated population variance of scores 9.27 Sample size 8 Group 2 Mean 22.17 Estimated population variance of scores 6.97 Sample Size 6 38. Which of the following is true if the statistical results of a study was t(5) = 10.365, p < .05 for an independent t test? a. The sample size for Group 1 is 5 b. It is not statistically significant c. Group 1 has a greater mean score than Group 2 d. Retain null hypothesis
c. Group 1 has a greater mean score than Group 2
2. Personality traits affect academic performance in college students who attend universities in the United States. What is the explanatory variable? a. College students b. Academic performance c. Personality traits d. University students in the United States
c. Personality traits
21. When figuring the pooled population variance estimate in a t-test for independent means, a. The variance of at least one of the original populations must be known, as opposed to estimated, but the other can be estimated from sample scores. b. The variance of BOTH of the original populations must be known, as opposed to estimated. c. The estimated population variance based on each of the samples is computed in such a way as to give more weight to the estimate based on more participants (sample size or degrees of freedom). d. The scores from both samples are combined to form a single sample, and the estimated variance is figured in the usual way using this combined sample.
c. The estimated population variance based on each of the samples is computed in such a way as to give more weight to the estimate based on more participants (sample size or degrees of freedom).
24. If a research article presented the results of an analysis of variance examining the effects of different classifications of horror movies and enjoyment as, "F (9, 81) = 1.20, p > .05," which of the following statements are true? a. There were 9 types of horror movies being studied. b. There were significant differences in enjoyment levels across horror movies. c. There were not significant differences in enjoyment levels across horror movies. d. There were 82 participants.
c. There were not significant differences in enjoyment levels across horror movies.
12. Which of the following is a medium effect size? a. 10 b. -.20 c. .80 d. -.50
d. -.50
3. A distribution is positively skewed. The measures of central tendency are most likely to be in this order. a. Mean=30, median = 50, mode = 70 b. Mean = 30, median = 70, mode = 50 c. Mean = 50, median = 50, mode = 50 d. Mean= 70, median = 50, mode = 30
d. Mean= 70, median = 50, mode = 30
Is there a difference in memory across different types of studying behaviors: rock music (Group 1), white noise (Group 2), and silence (Group 3)? Use a 5% p level. Group 1: 4 2 3 Group 2: 7 7 4 Group 3: 12 15 18 39. What is the IV and the DV, in order? a. Memory, Music b. Studying, Memory c. Silence, Studying d. Music, Memory
d. Music, Memory
Group 1 Mean 6.13 Estimated population variance of scores 9.27 Sample size 8 Group 2 Mean 22.17 Estimated population variance of scores 6.97 Sample Size 6 33. What is the shape of this comparison distribution? a. Left skewed b. Normal c. Rectangular d. Right skewed
d. Right skewed???????
14. A business owner investigates if a new advertising campaign has an effect on sales. After years of collecting data, he found that the mean sales score is generally 100 across stores with a standard deviation of 10. What should the sales score be after implementing the new advertising campaign to get a medium effect size? Choose the best solution. a. [(.80) + 100]/10 b. +.80(10) + 100 c. +0.50(10) + 100 d. [(.50) + 100]/10
d. [(.50) + 100]/10???????
20. When using a t table, the degrees of freedom used for a t-test for independent means is a. the degrees of freedom for sample 1, divided by the sum of the degrees of freedom for both groups. b. the average of the degrees of freedom for the two groups. c. the sum of the two sample sizes, minus one. d. the sum of the degrees of freedom for the two groups.
d. the sum of the degrees of freedom for the two groups.
40. Which of the following are true for an ANOVA? a. If the omnibus test is significant you conduct a paired comparison b. The estimated population variance within groups is the same as the omnibus test when during the paired comparison c. We assume homogeneity of variance d. Want the between group variance to be larger than the within group variance e. All of the above
e. All of the above
41. What does the estimated between group population variance signify? e. The spread of standard deviation in between groups f. The spread of scores within each group g. The spread of mean scores across the different groups h. The width of the comparison distribution.
g. The spread of mean scores across the different groups
42. What does the estimated within group population variance signify? i. Alpha j. Power k. Spread of scores due to other factors besides the condition being studied l. Effect size
k. Spread of scores due to other factors besides the condition being studied
44. Why do we need to conduct a post hoc test (e.g., Scheffe correction or Bonferroni correction) m. To control for False positives n. To control for False negatives o. To control for Power p. To reduce confounds in the experiment.
p. To reduce confounds in the experiment.
45. How many paired comparisons can be analyzed with 5 groups (A, B, C, D, E). By how much would the type one error rate be inflated if we used a p level of 5%? q. 10, 5% r. 5, 5% s. 10, 50% t. 5, 50%
s. 10, 50%
16. The population mean of the comparison group is 20 and the population mean of the experimental group is 35. The estimated population variance is 36. How do you compute the effect size? a. (35-20)/ 6 b. (35-20)/ 36 c. (20-35)/6 d. (20-35)/6
a. (35-20)/ 6
13. A study concluded that vaccines protected patients from a deadly disease when it actually did not provide protection. Choose the term that is associated with the research decision described. a. Beta b. Alpha c. Power d. Confound
a. Beta
1. What is the level of measurement for time using the 12-hour cycle (1:00, 2:00, 3:00, etc.) a. Interval b. Nominal c. Ratio d. Ordinal
a. Interval
5. The particular set of people enrolled in a study intended to be representative of a larger population is a(n) __________. a. Sample b. Control sample c. Treatment sample d. Comparison population
a. Sample
28. A researcher wants to know if casino staff are more anxious than the general population of people. The average anxiety score in the normal population is 22. The population standard deviation is 3. The one casino staff member that he surveyed for his research had an anxiety score of 25.5. Using the .05 probability level, find out if casino staff members are significantly more likely to be more anxious than the general population. What is the null hypothesis (H2)? a. The population mean anxiety score of casino workers is less than or equal to the population mean score of the general population. b. The population mean anxiety score of casino workers is more than or less than the population mean score of the general population. c. The population mean anxiety score of casino workers is greater than the population mean score of the general population. d. The population mean anxiety score of casino workers is equal to the population mean score of the general population.
a. The population mean anxiety score of casino workers is less than or equal to the population mean score of the general population.
22. A social psychologist interested in cultural differences compared women of two ethnic groups on a Role Approval Index on which high scores indicated high degrees of approval of one's own social role. The results were as follows. Ethnic Group A: N = 15 M = 55 S2 = 6.5 Ethnic Group B: N = 23 M = 51 S2 = 4.5 What is the pooled estimate of the population variance? a. [(14 / 36) (6.5)] + [(22 / 36) (4.5)] = 5.28 b. [(15 / 38) (6.5)] + [(23 / 38) (4.5)] = 5.29 c. [(15 / 38) (6.5)] + [(23 / 38) (4.5)] = 5.29 d. [(14 / 22) (6.5)] + [(22 / 14) (4.5)] = 11.21
a. [(14 / 36) (6.5)] + [(22 / 36) (4.5)] = 5.28
17. When the results of a t test are presented in a research article, the number(s) in parentheses that directly follow the "t" is(are) the __________. a. degrees of freedom b. t sample score c. cut off value d. p level
a. degrees of freedom
27. A researcher assesses the level of a particular hormone in the blood in five patients before and after they begin taking a hormone treatment program. What kind of statistical test would you suggest to this researcher? a. dependent t test b. independent t test c. correlation d. ANOVA e. z test
a. dependent t test
9. The comparison distribution when testing a hypothesis involving a sample of more than one participant is a(n) __________. a. distribution of means b. distribution of scores c. distribution of mean difference scores d. distribution of differences between means
a. distribution of means
18. When conducting a t-test for dependent means, μM a. is always equal to 0. b. is always equal to 1. c. is always equal to -1. d. depends on the population
a. is always equal to 0.
29. Which of the research scenarios below would be restated with the following statistical symbols? H1: µ1 < µ2 H2: µ1 ≥ µ2 a. A researcher wants to test if there is a significant difference in the recovery time of young adults and the general population. b. A researcher wants to test if the recovery time of young adults would be significantly less than the general population. c. A researcher wants to test if the recovery time of young adults would be significantly greater than the general population. d. None of the above.
b. A researcher wants to test if the recovery time of young adults would be significantly less than the general population.
25. Select the correct statement: a. An ANOVA is usually used to compare two groups, while a t-test for independent means can be used to compare two or more groups. b. An ANOVA can be used to compare three or more groups, while a t-test for independent means cannot be used to compare more than two groups. c. An ANOVA is conducted before the experiment, while a t-test for independent means is conducted after the experiment. d. An ANOVA includes the computation of correlations as part of the analysis, while a t-test does not include these computations.
b. An ANOVA can be used to compare three or more groups, while a t-test for independent means cannot be used to compare more than two groups.
Group 1 Mean 6.13 Estimated population variance of scores 9.27 Sample size 8 Group 2 Mean 22.17 Estimated population variance of scores 6.97 Sample Size 6 35. This is a comparison distribution of a. Scores b. Means c. Differences between mean scores d. Mean difference scores
b. Means ???????????
6. There are ceiling effects found in Psychopathy scores of convicted murderers. Why is another term that researchers can use to describe the data? a. Positively skewed b. Negatively skewed c. Rectangular d. Bimodal
b. Negatively skewed
30. A researcher wants to know if wearing a mask has an effect on school performance. Which of the following scenarios would reflect a sample t-test? a. The performance scores are collected from a sample of 50 people. The mean score will be compared with the performance scores of the general population of students with an unknown standard deviation. b. The performance scores are collected from a sample of 50 people. The mean score will be compared with the performance scores of the general population with a known mean and standard deviation. c. The performance scores are collected from a sample of 50 people. The mean score will be compared with the performance scores of another sample of 50 people who did not wear a mask during the pandemic. d. The performance scores are collected from a sample of 50 people while not wearing a mask and again while wearing a mask.
b. The performance scores are collected from a sample of 50 people. The mean score will be compared with the performance scores of the general population with a known mean and standard deviation. ??????
43. If the F statistical notation of a study is F(7, 32) = 143, p < 1%, which of the following statements is true: a. There are 32 groups being compared b. There are 8 different groups being compared c. There are 7 different groups being compared d. It is not statistically significant.
b. There are 8 different groups being compared
4. When __________ are summed, the result will always equal zero. a. standard deviation scores b. deviation scores c. squared deviations d. raw scores e. z scores
b. deviation scores
19. The comparison distribution in a t test for dependent means is a distribution of: a. differences between means b. means of difference scores (mean difference scores) c. dependent means d. independent means
b. means of difference scores (mean difference scores)
15. The test used to reach a decision about the null hypothesis when the population variance is unknown is the __________ test. a. directional b. t c. z d. one-tailed
b. t
26. A researcher is interested in whether people are able to identify emotions correctly when they are extremely tired. It is known that using a particular method of measurement, the accuracy ratings of people in the general population (who are not extremely tired) are normally distributed with a mean of 82 and a variance of 20. In the present study, the research arranges to test 50 people who had no sleep the previous night. The mean accuracy for the 50 individuals was 78. What kind of statistical test would you use? a. z test for more than one sample b. z test for a sample of one c. independent t test d. dependent t test e. ANOVA
b. z test for a sample of one
Group 1 Mean 6.13 Estimated population variance of scores 9.27 Sample size 8 Group 2 Mean 22.17 Estimated population variance of scores 6.97 Sample Size 6 36. What is the degrees of freedom total? a. 7 b. 8 c. 12 d. 14
c. 12
Group 1 Mean 6.13 Estimated population variance of scores 9.27 Sample size 8 Group 2 Mean 22.17 Estimated population variance of scores 6.97 Sample Size 6 34. What is the mean of this comparison distribution? a. 0 b. 5 c. 7 d. 2
c. 7 ????????
