Question 1

The example showing a negative relationship between speed and accuracy tells us that

Accepted Answer

A)  the slowest responders are always the most accurate. 
B)  the fastest responders are always the most accurate. 
C)  on average, slower responders are more accurate than faster responders. 
D)  speed is a virtue. 
A)  the slowest responders are always the most accurate. 
B)  the fastest responders are always the most accurate. 
C)  on average, slower responders are more accurate than faster responders. 
D)  speed is a virtue. C

Question 2

When we use heterogeneous subsamples of data, such as older and younger subjects, the resulting correlation between intelligence and education could

Accepted Answer

A)  tell you more about the relationship between Age and Education than between Intelligence and Education. 
B)  be very misleading. 
C)  represent the relationship between Education and Intelligence accurately. 
D)  all of the above 
A)  tell you more about the relationship between Age and Education than between Intelligence and Education. 
B)  be very misleading. 
C)  represent the relationship between Education and Intelligence accurately. 
D)  all of the above D

Question 3

The difference between a point biserial coefficient and a normal Pearson correlation coefficient is that

Accepted Answer

A)  a point biserial correlation is based on two continuous variables. 
B)  a point biserial correlation is based on one dichotomous variable and one continuous variable. 
C)  a point biserial correlation is based on two dichotomous variables. 
D)  the kind of variable has nothing to do with the issue. 
A)  a point biserial correlation is based on two continuous variables. 
B)  a point biserial correlation is based on one dichotomous variable and one continuous variable. 
C)  a point biserial correlation is based on two dichotomous variables. 
D)  the kind of variable has nothing to do with the issue. B

Question 4

Restricted range has no effect on correlation coefficients.

Accepted Answer

A) True 
 B)False

Question 5

A curvilinear relationship is one in which

Accepted Answer

A)  one variable always increases as the other increases. 
B)  as X increases, Y will increase and then level off or fall. 
C)  as X increases, Y will decrease and then level off or rise. 
D)  both b and c 
A)  one variable always increases as the other increases. 
B)  as X increases, Y will increase and then level off or fall. 
C)  as X increases, Y will decrease and then level off or rise. 
D)  both b and c

Question 6

A newspaper headline writer found that the more adjectives she put in the titles of her articles, the greater the number of newspapers that were sold that day. This relationship between numbers of adjectives and newspaper sales must be

Accepted Answer

A)  significantly positive. 
B)  significantly negative. 
C)  monotonic. 
D)  positive. 
A)  significantly positive. 
B)  significantly negative. 
C)  monotonic. 
D)  positive.

Question 7

The data illustrated in the graph below suggest

Accepted Answer

A)  that there is a strong positive relationship between height and weight. 
B)  that there is no relationship between height and weight. 
C)  that some other variable is involved in the relationship. 
D)  that these data are unreliable. 
A)  that there is a strong positive relationship between height and weight. 
B)  that there is no relationship between height and weight. 
C)  that some other variable is involved in the relationship. 
D)  that these data are unreliable.

Question 8

In testing the significance of a correlation coefficient, the degrees of freedom are

Accepted Answer

A)  N 
B)  N - 1 
C)  N - 2 
D)  N - 3 
A)  N 
B)  N - 1 
C)  N - 2 
D)  N - 3

Question 9

Correlation coefficients can range from -1 to 1.

Accepted Answer

A) True 
 B)False

Question 10

A reliable correlation is one that

Accepted Answer

A)  is significantly different from 0. 
B)  is likely to be closely approximated in a future study. 
C)  is close to 1.00. 
D)  is non-negative. 
A)  is significantly different from 0. 
B)  is likely to be closely approximated in a future study. 
C)  is close to 1.00. 
D)  is non-negative.

Question 11

Point biseral correlation is used when one of the variables is dichotomous.

Accepted Answer

A) True 
 B)False

Question 12

Which of the following represents a closer relationship between two variables?

Accepted Answer

A)  r = .00 
B)  r = .50 
C)  r = -.30 
D)  r = -.65 
A)  r = .00 
B)  r = .50 
C)  r = -.30 
D)  r = -.65

Question 13

Professor Falls wants to determine if there is a relationship between frequent hearing of a startle stimulus and hearing loss. He ran a regression and obtained an r value of .60. Which of the following best summarizes what this result means?

Accepted Answer

A)  60% of hearing loss is accounted for by frequency of hearing startle stimuli. 
B)  36% of the variability in hearing loss can be accounted for by variability in the hearing of startle stimuli. 
C)  36% of startle stimuli cause hearing loss. 
D)  60% of hearing loss is caused by startle stimuli. 
A)  60% of hearing loss is accounted for by frequency of hearing startle stimuli. 
B)  36% of the variability in hearing loss can be accounted for by variability in the hearing of startle stimuli. 
C)  36% of startle stimuli cause hearing loss. 
D)  60% of hearing loss is caused by startle stimuli.

Question 14

Correlation cannot be used to test associations between two dichotomous variables.

Accepted Answer

A) True 
 B)False

Question 15

An intercorrelation matrix is one that

Accepted Answer

A)  presents the correlations of each variable with each other variable. 
B)  is symmetric. 
C)  has as many rows as it does columns. 
D)  all of the above 
A)  presents the correlations of each variable with each other variable. 
B)  is symmetric. 
C)  has as many rows as it does columns. 
D)  all of the above

Question 16

In the scatterplot for the data in the previous question, the biggest outliers are likely to be

Accepted Answer

A)  Portugal and Sweden. 
B)  Japan and Ireland . 
C)  Denmark and Sweden. 
D)  the U.S.A. and West Germany. 
A)  Portugal and Sweden. 
B)  Japan and Ireland . 
C)  Denmark and Sweden. 
D)  the U.S.A. and West Germany.

Question 17

A significant correlation is one which

Accepted Answer

A)  has a great deal of meaning. 
B)  means that the variables are not linearly independent. 
C)  is very hard to find. 
D)  is most likely to occur when the true correlation is near 0. 
A)  has a great deal of meaning. 
B)  means that the variables are not linearly independent. 
C)  is very hard to find. 
D)  is most likely to occur when the true correlation is near 0.

Question 18

The correlation between two variables is a measure of the degree to which

Accepted Answer

A)  points cluster together around some best-fitting straight line. 
B)  differences in one variable can be predicted from differences in the other variable. 
C)  one variable varies with the other variable. 
D)  all of the above 
A)  points cluster together around some best-fitting straight line. 
B)  differences in one variable can be predicted from differences in the other variable. 
C)  one variable varies with the other variable. 
D)  all of the above

Question 19

Correlations are typically used to examine mean differences between groups.

Accepted Answer

A) True 
 B)False

Question 20

Which r-value represents the strongest correlation?

Accepted Answer

A)  +.50 
B)  -.50 
C)  -.75 
D)  1.65 
A)  +.50 
B)  -.50 
C)  -.75 
D)  1.65

Exam 9: Correlation

The example showing a negative relationship between speed and accuracy tells us that

When we use heterogeneous subsamples of data, such as older and younger subjects, the resulting correlation between intelligence and education could

The difference between a point biserial coefficient and a normal Pearson correlation coefficient is that

Restricted range has no effect on correlation coefficients.

A curvilinear relationship is one in which

A newspaper headline writer found that the more adjectives she put in the titles of her articles, the greater the number of newspapers that were sold that day. This relationship between numbers of adjectives and newspaper sales must be

The data illustrated in the graph below suggest

In testing the significance of a correlation coefficient, the degrees of freedom are

Correlation coefficients can range from -1 to 1.

A reliable correlation is one that

Point biseral correlation is used when one of the variables is dichotomous.

Which of the following represents a closer relationship between two variables?

Professor Falls wants to determine if there is a relationship between frequent hearing of a startle stimulus and hearing loss. He ran a regression and obtained an r value of .60. Which of the following best summarizes what this result means?

Correlation cannot be used to test associations between two dichotomous variables.

An intercorrelation matrix is one that

In the scatterplot for the data in the previous question, the biggest outliers are likely to be

A significant correlation is one which

The correlation between two variables is a measure of the degree to which

Correlations are typically used to examine mean differences between groups.

Which r-value represents the strongest correlation?

Introduction

Basic Concepts

Displaying Data

Measures of Central Tendency

Measures of Variability

The Normal Distribution

Basic Concepts of Probability

Sampling Distributions and Hypothesis Testing

Regression

Multiple Regression

Hypothesis Tests Applied to Means: One Sample

Hypothesis Tests Applied to Means: Two Related Samples

Hypothesis Tests Applied to Means: Two Independent Samples

Power

One-Way Analysis of Variance

Factorial Analysis of Variance

Repeated-Measures Analysis of Variance

Chi-Square

Nonparametric and Resampling Statistical Tests

Meta-Analysis

Filters