1

1. What is the direction of this scatterplot?

   positive

   negative

1 points

QUESTION 2

1. Before calculating the correlation coefficient, it is advisable to create a _____ as a way of displaying the association between the two variables.

   A.	histogram
   B.	scatterplot
   C.	line graph
   D.	polygon

1 points

QUESTION 3

1. Order thescatterplotsby strength from lowest to strongest.

   a)

   b)

   c)

   - 1. 2. 3.

   a

   - 1. 2. 3.

   b

   - 1. 2. 3.

   c

1 points

QUESTION 4

1. A positive correlation between head size and foot size indicates that:

   A.	people with larger feet tend to have smaller heads.
   B.	people with larger feet also tend to have larger heads.
   C.	having a large head causes a person to have large feet.
   D.	having large feet causes a person to have a large head.

1 points

QUESTION 5

1. In a reanalysis of published studies, Twenge and Im (2007) found that for the time period 19582001, the need for social approval of people in the United States was negatively correlated with the U.S. violent crime rate during the same period (the correlation coefficient was 0.31). This correlation means that:

   A.	the need for social approval prevented people from committing violent crimes.
   B.	the need for social approval spurred people to commit violent crimes.
   C.	as the need for social approval went up, the number of violent crimes decreased.
   D.	as the need for social approval went up, the number of violent crimes also increased.

1 points

QUESTION 6

1. What is the null hypothesis when testing for significance using the Pearson correlation coefficient?

   A.	r0
   B.	= 0
   C.	1=2
   D.	r= 0

1 points

QUESTION 7

1. What is the relationship between correlation and causation?

   A.	Correlation is sufficient for causation.
   B.	Correlation is both necessary and sufficient for causation.
   C.	Correlation is necessary for causation.
   D.	There is no relationship between correlation and causation.

1 points

QUESTION 8

1. Which of these correlation coefficients allows a perfect prediction of scores on one variable from knowledge of scores on the other variable?

   A.	0.50
   B.	1.00
   C.	2.00
   D.	0

1 points

QUESTION 9

1. The Pearson correlation coefficient is symbolized by:

   A.	c
   B.	t
   C.	r
   D.	x

1 points

QUESTION 10

1. Which of these values indicates the strongest relationship between two variables?

   A.	0.72
   B.	0.25
   C.	0.59
   D.	0.65

1 points

QUESTION 11

1. If one wishes to assess the relation between a farming county's average annual temperature and the crop yield, it may be important to take into account the overlapping variability that crop yield and temperature share with rainfall. To do so, one would compute a:

   A.	partial correlation.
   B.	coefficient alpha.
   C.	concurrent validity.
   D.	split-half reliability.

1 points

QUESTION 12

1. Find the Mean Squared Between. The sample sizes for each of the groups is 28 and the sample means are as follows 22, 13, 17. Round tothe second decimal place if needed.

1 points

QUESTION 13

1. If the F-statistic is not significant for a Within Subjects ANOVA,we shouldconduct follow up t-tests.

   True

   False

1 points

QUESTION 14

1. If the sample sizes for each group is28,and the sum of squares for each group is as follows:3,3,and7,what is the Mean Squared Within?Round to the second decimal place,if needed.

1 points

QUESTION 15

1. Ifthe F-statistic is significant and you are comparing3sample means,what can you conclude?

   The mean for sample1is different than the mean for sample3.

   The mean for sample2is different than the mean for sample3.

   The mean for sample1is different than the mean for sample2.

   At least one of the sample means is different.

1 points

QUESTION 16

1. You are conducting a dependent t-test: There is a repeated measure design and there is apreand post test. What is the average of the difference scores?Your difference scores should be calculated like this: Difference =pre- post. Round to the second decimal place, if needed.

   pre	post
   27	91
   83	49
   89	69

1 points

QUESTION 17

1. What number must the F-statistic be higher than to be significant?

   Note:Being greater than this number, does not guaranteeit will be significant (depends on the degrees of freedom), but it must at least greater than this number to be significant.

1 points

QUESTION 18

1. The _____ sum of squares is unique to the within-subjects design.

   A.	subjects
   B.	total
   C.	between-groups
   D.	within-groups

1 points

QUESTION 19

1. What is the correct formula for between-groups degrees of freedom?

   A.	Ngroups 1
   B.	n 2
   C.	n 1
   D.	Ntotal 1

1 points

QUESTION 20

1. The one-way within-groups design can be viewed as an extension of which other research design because of its ability to analyze data from more groups?

   A.	paired-samplesttest
   B.	between-groups ANOVA
   C.	independent-samplesttest
   D.	TukeyHSDtest

1 points

QUESTION 21

1. A researcher wants to examine people's preference for pets by having 10 people act as foster owners for four different types of family pets: dogs, cats, birds, and fish. The participants will foster each type of pet for one week, and a scale measure will be used to assess preference. Which research design should be used?

   A.	one-way within-groups ANOVA
   B.	paired-samplesttests
   C.	one-way between-groups ANOVA
   D.	correlation

1 points

QUESTION 22

1. A dependent-samplesttest is used when there are _____ groups, and a within-groups ANOVA is used when there are at least _____ groups.

   A.	2; 3
   B.	3; 2
   C.	1; 2
   D.	1; 3

1 points

QUESTION 23

1. What is the degrees of freedom error for a Within Subjects ANOVA,if the number of time points is3and the number of subjects is 28?

1 points

QUESTION 24

1. Suppose there is a repeated measure design. There are 4 time pointsand 3 subjects. The mean for subject 1 is 8, the mean for subject 2 is 8, and the mean for subject 3 is 7. What is the? Hint: Find the grand mean first from the subject's means. Make sure you take in account the number of time points. Round to the second decimal place if need.

1 points

QUESTION 25

1. If the F-statistic is significant for a Within Subjects ANOVA, we should do what type of follow tests?

   Correlations

   Chi-Square Tests

   Independent t-tests

   Dependent t-tests

1 points

QUESTION 26

1. If the sample size is51and the t-statistic is-2,what is the p-value fora greater than research hypothesis?

   .953893

   .984278

   .974526

   .943921

1 points

QUESTION 27

1. If theis85and theis15,what is the?

1 points

QUESTION 28

1. You are conducting an independent t-test to compare men and women on a performance test. If the standard deviation for men 6 for a sample of 45 and the standard deviation for women is 4 for a sample of 28, what is the pooled standard deviation? Round to the second decimal place as needed.

1 points

QUESTION 29

1. If theis62and theis30,what is the F-statistic?Round to the second decimal place,if needed.

1 points

QUESTION 30

1. A professor is not sure which exam(1or2)that students do better on.The professor samples10students and records the exam1and exam2scores for each of the10students.Thus,there are20observations.What should the research hypothesis be?Assume that difference scores arecalculatedas such:difference=exam2-exam1.

1 points

QUESTION 31

1. A dependent t-test is used when your sample is paired.

   True

   False

1 points

QUESTION 32

1. For an independent t-test: It is hypothesized that men score higher than women. What could be the research hypothesis?

1 points

QUESTION 33

1. A professor believes that students in her class do better on the firsttest than on thesecondtest. The professor samples 10 students and records the exam 1 and exam 2 scores for each of the 10 students. Thus, there are 20 observations. What should the research hypothesis be?Assume that difference scores arecalculatedas such: difference = exam 2 - exam 1.

1 points

QUESTION 34

1. For an independent t-test: It is hypothesized that men score higher than women. What could be the research hypothesis?

1 points

QUESTION 35

1. What would be the decision for the following paired-samplesttest:t(24) = 1.11,p> 0.05?

   A.	reject the null hypothesis
   B.	reject the research hypothesis
   C.	fail to reject the research hypothesis
   D.	fail to reject the null hypothesis

1 points

QUESTION 36

1. What is the mean difference of the following difference scores: 2, 19, +17, 22, 6?

   A.	15.57
   B.	6.96
   C.	0.92
   D.	6.40

1 points

QUESTION 37

1. A negatively skewed distribution would most likely violate which assumption?

   A.	dependent variable is scale
   B.	random assignment
   C.	random selection
   D.	normality

1 points

QUESTION 38

1. Twenty people participate in a weight-loss program for two months. Their weights after the two months are compared to their starting weights. What kind of mean difference might be expected if the null hypothesis is true for a paired-samplesttest?

   A.	no change in weight or weight gain, indicating that the program does not work
   B.	weight loss, indicating that the program does not work
   C.	a negative mean difference, indicating significant weight loss
   D.	a loss of pounds, on average, showing the effectiveness of the program

1 points

QUESTION 39

1. Assume the following for a paired-samplesttest:N= 12,M_difference= 635.65,s= 608.50. What is thetstatistic?

   A.	183.50
   B.	3.62
   C.	52.97
   D.	1.04

1 points

QUESTION 40

1. What is the paired-samplesttest for the following difference scores: 8, 3, 4.5, 7, 11.1, 9?

   A.	2.97
   B.	5.86
   C.	1.21
   D.	7.10

1 points

QUESTION 41

1. Assume the following for a paired-samplesttest:N= 9,M_difference= 13.19,s= 22.3. What is thetstatistic?

   A.	0.59
   B.	7.43
   C.	1.77
   D.	4.40

1 points

QUESTION 42

1. For the following data, what is the mean of the difference scores?

   Before	After
   110	103
   98	104
   89	97
   114	127

   A.	8.52
   B.	5.00
   C.	1.17
   D.	4.26

1 points

QUESTION 43

1. If theis 15,theis 9,and theis 8, what should the F-statistic be for a Within Subjects ANOVA?Round to the second decimal place, if needed.Hint:You only need 2 of the numbers for the calculation.

1 points

QUESTION 44

1. As the variability of between-groups means increases, theFstatistic decreases.

   True

   False

1 points

QUESTION 45

1. Dr. Jameson wanted to know if IQ scores differed between male and female participants in his study. He gave 28 participants an IQ test and then compared IQ scores for gender differences. He hypothesized that there would be a statistically significant gender difference in IQ scores. Contrary to Dr. Jameson's hypothesis, there were no differences in IQ scores between men and women in his study. Based on the information provided, does this study meet the assumption of normality? Why or why not?

   A.	Yes; the population is likely to be normally distributed because the sample size is less than 30.
   B.	We do not know whether it is normally distributed and the sample size is not at least 30 participants.
   C.	Yes; it is normally distributed because the sample size is large.
   D.	No; it is not normally distributed because the small sample size is small.

1 points

QUESTION 46

1. Mehl (2007) published in the journalSciencethe results of an extensive study of 396 men and women comparing the number of words uttered per day by each sex. Which statistical test should Mehl use to analyze the data?

   A.	ztest
   B.	single-samplettest
   C.	independent-samplesttest
   D.	dependent-samplesttest

1 points

QUESTION 47

1. The results of an independent-samplest-test weret(18) = 2.11,p< 0.05. These results are:

   A.	statistically significant.
   B.	meaningful.
   C.	not statistically significant.
   D.	generalizable.

1 points

QUESTION 48

1. Dr. Jameson wanted to know if IQ scores differed between male and female participants in his study. He gave 28 participants an IQ test and then compared IQ scores for gender differences. He hypothesized that there would be a statistically significant gender difference in IQ scores. Contrary to Dr. Jameson's hypothesis, there were no differences in IQ scores between men and women in his study. From the results of the study, Dr. Jameson must _____ the null hypothesis and _____ the research hypothesis.

   A.	retest; reject
   B.	reject; fail to reject
   C.	fail to reject; reject
   D.	reject; retest

1 points

QUESTION 49

1. The statement On average, older adults have the same response time as younger adults is an example of:

   A.	effect size.
   B.	the null hypothesis.
   C.	the research hypothesis.
   D.	statistical significance.

1 points

QUESTION 50

1. In a(n) _____, a within-groups design with two groups is used to compare the distribution of mean difference scores.

   A.	ztest
   B.	independent-samplesttest
   C.	single-samplettest
   D.	paired-samplesttest