Psych 541 Quiz 5 Summer 2017
Psych 541 Quiz 5 Summer 2017 47 points
1. IfSST = 56 andSSB = 14,SSW = _________.
a. 34
b. 6
c. -6
d. 42
2. If dfB = 4 and dfW = 20, usingalpha = 0.05,Fcrit = _________.
a. 2.87
b. 3.10
c. 3.74
d. 6.22
3. An investigator conducts an experiment involving the effects of three levels of a drug on memory. Subjects are randomly assigned to one of three conditions. A different drug level is administered in each condition. Memory is measured 10 minutes after each subject receives the drug. The following scores are recorded. The higher the score, the better the memory.
Drug Level one two three
6 9 14
5 7 13
8 9 15
2 13 19
After conducting a one-way ANOVA of the above data, which of the following is the variability among the group means _________.
a. 6.50
b. 15.5
c. 100.75
d. 201.5
4. Refer to the drug study. After conducting a one-way ANOVA of the above data, which of the following is the average variance within each of the three groups.
a. 6.50
b. 15.5
c. 100.75
d. 201.5
5. Refer to the drug study. After conducting a one-way ANOVA of the above data, which of the following is the F critical using alpha at .05.
a. 3.63
b. 4.26
c. 5.12
d. 4.46
6. If I have four groups, and a total of 40 subjects in the entire experiment, how many within groups degrees of freedom do I have.
a. 39
b. 3
c. 36
d. 28
7. Refer to the drug study. When calculating the total sum of squares, I utilize the following expression: SStotal = 1460 – (120)2/12 which equals 260. The SS between = (21)2/4 + (38)2/4 + (61)2/4 - (120)2/12 which equals 201.5. Based on this information which of the following is the numerator of the average variance within each group.
a. 1460
b. 201.5
c. 120
d. 58.5
8. Refer to the drug study. When calculating the total sum of squares, I utilize the following expression: SStotal = 1460 – (120)2/12 which equals 260. The SS between = (21)2 + (38)2 + (61)2- (120)2/12 which equals 201.5. Based on this information which of the following is the numerator of the total variance among all the scores.
a. 1460
b. 201.5
c. 120
d. 260.
9. Refer to the drug study Estimate the size of the effect.Using omega squared.
a. 0.5109
b. 0.6698
c. 1.6633
d. 0.7073
10. Refer to drug study. Estimate the size of the effect using Cohen’s f.
a. 1.4244
b. 0.6698
c. 1.6633
d. 1.5546
11. (12 points) In the space below conduct pairwise comparisons using the Tukey, Neuman Keuls, LSD and Bonferroni for the drug study above. Place the work for each test (show all work) below the label for each test and be specific when you state you conclusions.
(3 points) Tukey test (show all work for Tukey below)
(3 points) Neuman Keuls (show all work for Neuman Keuls below)
( 3 points) LSD (show all work for LSD below)
(3 points) Bonferroni (show all work for Bonferroni below)
11. A sleep researcher conducts an experiment to determine whether sleep loss affects the ability to maintain sustained attention. Fifteen individuals are randomly divided into the following three groups of 5 subjects each: group 1, which gets the normal amount of sleep (7-8 hours); group 2, which is sleep-deprived for 24 hours; group 3, which is sleep-deprived for 48 hour. And group 4 which is sleep deprived for 72 hours. All four groups are tested on same auditory vigilance task. Subjects are presented with half-second tones spaced at irregular intervals over a 1-hour duration. Occasionally, one of the tones is slightly shorter than the rest. The subject’s task is to detect the shorter tones. The following percentages of correct detections were observed:
Normal Sleep-Deprived Sleep-Deprived Sleep Deprived
Sleep for 24 Hours for 48 Hours for 72 Hours
85 60 60 55
83 58 48 47
76 76 38 27
64 52 47 41
75 63 50 43
After conducting a one way ANOVA, which of the following is theSSBetween?
a. 3422.4
b. 2234.4
c. 96.555
d. 1953.3
12. Refer to the sleep study.SSW = _________.
a. 3422.4
b. 2234.4
c. 96.555
d. 1256.4
13. Refer to the sleep study. Fobt = _________.
a. 20.99
b. 10.99
c. 14.528
d. 3.24
14. Refer to the sleep study. Based on the F obtained which of the following below is the amount of variability among the means expected by chance.
a. 1140.8
b. 78.525
c. 3422
d. 3255
15.Refer to the sleep study. Usingaplha = 0.05,Fcrit = _________.
a. 4.33
b. 3.63
c. 2.96
d. 3.24
16. Refer to the sleep study. Usingalpha = 0.05, what do you conclude?
a. rejectH0; sleep deprivation has the same effect on vigilance at all levels
b. rejectH0; sleep deprivation does not have the same effect on vigilance at all levels
c. retainH0; we cannot conclude that sleep deprivation influences vigilance
d. acceptH0; sleep deprivation has the same effect on vigilance at all levels
17. Refer to sleep study Estimate the size of the effect.Using omega squared.
a. 0.5109
b. 0.6698
c. 1.6633
d. 0..5678
18. Refer to sleep study. Estimate the size of the effect using Cohen’s f.
a. 1.4244
b. 0.6698
c. 1.6633
d. 0.5678
19. If the variability of the cell means around the grand mean is no greater than you would
expect by chance, then you would expect your F ratio to be equal to ?
a. 10
b. 0
c. 2.34
d. 1.00
20. Which of the following would cause Fobtainedto increase?
a. an increase in the difference between the means
b. an increase in the within-groups variability
c. an increase in the magnitude of the independent variable's effect
d. a and b
e. a and c
21. Which of the following assumptions of the analysis of variance if violated is especially problematic if you have unequal sample sizes.
a. normality
b. homogeneity of variance
c. independence
d. odd numbers
22. TheF ratio increases as _________.
a. the variability between means increases relative to the variability within groups
b. the variability between means decreases relative to the variability within groups
c. the total variability increases
d. the total variability decreases
e. the variability within groups remains the same
23. Which of the follow will result if you violate the assumptions of the F test, especially if you have heterogeneity of variance and unequal n?
a) Power will decrease
b) Probability of a type 2 error will increase
c) Probability of a type 1 error will increase
d) The world will end
24.(12 points)In the space below conduct pairwise comparisons using the Tukey, Neuman Keuls, LSD and Bonferroni for the sleep study above. Place the work for each test (show all work) below the label for each test and be specific when you state you conclusions.
(3 points) Tukey test (show all work for Tukey below)
(3 points) Neuman Keuls (show all work for Neuman Keuls below)
(3 points) LSD (show all work for LSD below)
(3 points) Bonferroni (show all work for LSD below)
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Rating:
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