Question 1

The coefficient of determination allows you to

Accepted Answer

A)  determine the variance two variables have in common 
B)  draw cause-and-effect statements 
C)  predict X scores, given Y scores 
D)  quickly determine the regression coefficients. 
A)  determine the variance two variables have in common 
B)  draw cause-and-effect statements 
C)  predict X scores, given Y scores 
D)  quickly determine the regression coefficients. A

Question 2

The least squares method of finding a formula for a straight line

Accepted Answer

A)  is the same as the two-point method 
B)  was invented by Francis Galton 
C)  minimizes the error of the predictions in a special way 
D)  all of the other alternatives are correct. 
A)  is the same as the two-point method 
B)  was invented by Francis Galton 
C)  minimizes the error of the predictions in a special way 
D)  all of the other alternatives are correct. C

Question 3

The steeper the slope of the regression line,

Accepted Answer

A)  the more confidence you have in the accuracy of your predicted scores 
B)  the larger a is 
C)  the larger b is 
D)  all of the other alternatives are correct. 
A)  the more confidence you have in the accuracy of your predicted scores 
B)  the larger a is 
C)  the larger b is 
D)  all of the other alternatives are correct. C

Question 4

Data Set 6-5
Given the regression equation
 $\hat { Y }$ 
= 32 - 2X, where X is the number of complaints each quarter about a service man and Y is the number of months of employment.
-Refer to Data Set 6-5. The correlation coefficient of the data would be

Accepted Answer

A)  positive 
B)  negative 
C)  zero 
D)  cannot tell unless a and b are given, too. 
A)  positive 
B)  negative 
C)  zero 
D)  cannot tell unless a and b are given, too.

Question 5

The reliability of a test can be measured using a correlation coefficient.

Accepted Answer

A) True 
 B)False

Question 6

The denominator of the z score formula for the correlation coefficient is N.

Accepted Answer

A) True 
 B)False

Question 7

A Pearson product-moment correlation coefficient can be used to express the degree of relationship for which situation(s) below?

Accepted Answer

A)  A little anxiety produces poor results, a moderate amount produces good results, and a high level of anxiety produces poor results. 
B)  Early in training each trial helps only a little, but as training progresses, each trial causes a larger and larger gain. 
C)  For every extra year of growth in a pine forest, you can expect an increase of 10,000 board feet. 
D)  All of the other alternatives are correct. 
A)  A little anxiety produces poor results, a moderate amount produces good results, and a high level of anxiety produces poor results. 
B)  Early in training each trial helps only a little, but as training progresses, each trial causes a larger and larger gain. 
C)  For every extra year of growth in a pine forest, you can expect an increase of 10,000 board feet. 
D)  All of the other alternatives are correct.

Question 8

The coefficient of determination is the square of r.

Accepted Answer

A) True 
 B)False

Question 9

Look at the three sets of distributions below and, without any computation, label them as positive or negative correlations.
-$$\begin{array} { r r } 
\mathrm { X } & \mathrm { Y } \
\hline 6 & 12 \
5 & 11 \
5 & 10 \
3 & 10 \
1 & 2 \
- 2 & 1
\end{array}$$

Accepted Answer

A)  positive 
B) negative 
A)  positive 
B) negative

Question 10

Which statement below is correct?

Accepted Answer

A)  A Pearson correlation coefficient is appropriate for describing a curved relationship that exists between two variables. 
B)  Correlation coefficients can be used to establish cause and effect relations. 
C)  both descriptive alternatives are correct 
D)  neither of the descriptive alternatives is correct. 
A)  A Pearson correlation coefficient is appropriate for describing a curved relationship that exists between two variables. 
B)  Correlation coefficients can be used to establish cause and effect relations. 
C)  both descriptive alternatives are correct 
D)  neither of the descriptive alternatives is correct.

Question 11

The correlation coefficient was developed just before the year

Accepted Answer

A)  1600 
B)  1700 
C)  1800 
D)  1900. 
A)  1600 
B)  1700 
C)  1800 
D)  1900.

Question 12

Suppose you know that the regression coefficients for the line that predicts the height of pine trees from annual rainfall are a = 10, b = -1.0. Knowing this, you can conclude that the correlation coefficient for these data is

Accepted Answer

A)  positive 
B)  negative 
C)  perfect 
D)  none of the other alternatives are correct. 
A)  positive 
B)  negative 
C)  perfect 
D)  none of the other alternatives are correct.

Question 13

The regression equation described in your textbook is based on the least-squares method.

Accepted Answer

A) True 
 B)False

Question 14

A univariate distribution is required to calculate a correlation coefficient.

Accepted Answer

A) True 
 B)False

Question 15

Hemphill's analysis of thousands of published r's found that the lower third were  and the upper third were ___ .

Accepted Answer

A)  less than .20, greater than .30 
B)  less than .40, greater than .80 
C)  less than .50, greater than .60 
D)  less than .60, greater than .90. 
A)  less than .20, greater than .30 
B)  less than .40, greater than .80 
C)  less than .50, greater than .60 
D)  less than .60, greater than .90.

Question 16

There is only one regression line for a bivariate distribution.

Accepted Answer

A) True 
 B)False

Question 17

Suppose that in a correlation study you obtained values for only the lower half of the possible values of your two variables. When you calculated the correlation coefficient it was low. It's possible that there is a strong relationship that you missed because you

Accepted Answer

A)  did not pair the variables 
B)  failed to regress the variables 
C)  truncated the range 
D)  all of the other alternatives are correct. 
A)  did not pair the variables 
B)  failed to regress the variables 
C)  truncated the range 
D)  all of the other alternatives are correct.

Question 18

Data Set 6-6
 $$\begin{array} { l l } 
X & Y \
\hline 1 & 4 \
2 & 3 \
3 & 2
\end{array}$$
-The correlation coefficient in Data Set 6-6 is

Accepted Answer

A)  positive 
B)  negative 
C)  zero 
D)  none of the other alternatives are correct. 
A)  positive 
B)  negative 
C)  zero 
D)  none of the other alternatives are correct.

Question 19

The least squares method of finding a formula for a straight line

Accepted Answer

A)  is different from the two-point method for finding the formula 
B)  is the solution for finding a line through a scatterplot 
C)  minimizes the errors in prediction in a special way 
D)  all of the other alternatives are correct. 
A)  is different from the two-point method for finding the formula 
B)  is the solution for finding a line through a scatterplot 
C)  minimizes the errors in prediction in a special way 
D)  all of the other alternatives are correct.

Question 20

The scores below are from two different tests of self-esteem. $$\begin{array} { c c c } 
\text { Subject } & \text { Test A } & \text { Test B } \
\hline 1 & 10 & 7 \
2 & 9 & 8 \
3 & 9 & 6 \
4 & 8 & 9 \
5 & 6 & 4 \
6 & 5 & 6 \
7 & 5 & 5 \
8 & 3 & 3 \
9 & 1 & 2
\end{array}$$ 
a. Draw a scatterplot.
b. Calculate r.
c. Calculate the coefficient of determination and use it to write a conclusion about whether the two tests are measuring the same thing.
d. Calculate the regression coefficients and draw the regression line on the scatterplot you drew above.
e. Predict a score for Test B from a Test A score of 15.

Accepted Answer

a.@#IMG-DLM&
b.
\[\begin{array} { l l l } 
\Sigma

The coefficient of determination allows you to

The least squares method of finding a formula for a straight line

The steeper the slope of the regression line,

Data Set 6-5 Given the regression equation $\hat { Y }$ = 32 - 2X, where X is the number of complaints each quarter about a service man and Y is the number of months of employment. -Refer to Data Set 6-5. The correlation coefficient of the data would be

The reliability of a test can be measured using a correlation coefficient.

The denominator of the z score formula for the correlation coefficient is N.

A Pearson product-moment correlation coefficient can be used to express the degree of relationship for which situation(s) below?

The coefficient of determination is the square of r.

Look at the three sets of distributions below and, without any computation, label them as positive or negative correlations. - 6 12 5 11 5 10 3 10 1 2 -2 1

Which statement below is correct?

The correlation coefficient was developed just before the year

Suppose you know that the regression coefficients for the line that predicts the height of pine trees from annual rainfall are a = 10, b = -1.0. Knowing this, you can conclude that the correlation coefficient for these data is

The regression equation described in your textbook is based on the least-squares method.

A univariate distribution is required to calculate a correlation coefficient.

Hemphill's analysis of thousands of published r's found that the lower third were and the upper third were ___ .

There is only one regression line for a bivariate distribution.

Suppose that in a correlation study you obtained values for only the lower half of the possible values of your two variables. When you calculated the correlation coefficient it was low. It's possible that there is a strong relationship that you missed because you

Data Set 6-6 X Y 1 4 2 3 3 2 -The correlation coefficient in Data Set 6-6 is

The least squares method of finding a formula for a straight line

Introduction

Exploring Data: Frequency Distributions and Graphs

Exploring Data: Central Tendency

Exploring Data: Variability

Other Descriptive Statistics

Theoretical Distributions Including the Normal Distribution

Samples, Sampling Distributions, and Confidence Intervals

Hypothesis Testing and Effect Size: One-Sample Designs

Hypothesis Testing, Effect Size, and and Confidence Intervals: Two-Sample Designs

Analysis of Variance: One-Way Classification

Analysis of Variance: One-Factor Repeated Measures

Analysis of Variance: Factorial Design

Chi Square Tests

More Nonparametric Tests

Appendix: Grouped Frequency Distributions and Central Tendency

Filters

Exam 6: Correlation and Regression

The coefficient of determination allows you to

The least squares method of finding a formula for a straight line

The steeper the slope of the regression line,

Data Set 6-5 Given the regression equation Y^\hat { Y }Y^ = 32 - 2X, where X is the number of complaints each quarter about a service man and Y is the number of months of employment. -Refer to Data Set 6-5. The correlation coefficient of the data would be

The reliability of a test can be measured using a correlation coefficient.

The denominator of the z score formula for the correlation coefficient is N.

A Pearson product-moment correlation coefficient can be used to express the degree of relationship for which situation(s) below?

The coefficient of determination is the square of r.

Look at the three sets of distributions below and, without any computation, label them as positive or negative correlations. - 6 12 5 11 5 10 3 10 1 2 -2 1

Which statement below is correct?

The correlation coefficient was developed just before the year

Suppose you know that the regression coefficients for the line that predicts the height of pine trees from annual rainfall are a = 10, b = -1.0. Knowing this, you can conclude that the correlation coefficient for these data is

The regression equation described in your textbook is based on the least-squares method.

A univariate distribution is required to calculate a correlation coefficient.

Hemphill's analysis of thousands of published r's found that the lower third were and the upper third were ___ .

There is only one regression line for a bivariate distribution.

Suppose that in a correlation study you obtained values for only the lower half of the possible values of your two variables. When you calculated the correlation coefficient it was low. It's possible that there is a strong relationship that you missed because you

Data Set 6-6 X Y 1 4 2 3 3 2 -The correlation coefficient in Data Set 6-6 is

The least squares method of finding a formula for a straight line

Introduction

Exploring Data: Frequency Distributions and Graphs

Exploring Data: Central Tendency

Exploring Data: Variability

Other Descriptive Statistics

Theoretical Distributions Including the Normal Distribution

Samples, Sampling Distributions, and Confidence Intervals

Hypothesis Testing and Effect Size: One-Sample Designs

Hypothesis Testing, Effect Size, and and Confidence Intervals: Two-Sample Designs

Analysis of Variance: One-Way Classification

Analysis of Variance: One-Factor Repeated Measures

Analysis of Variance: Factorial Design

Chi Square Tests

More Nonparametric Tests

Appendix: Grouped Frequency Distributions and Central Tendency

Filters

Data Set 6-5 Given the regression equation $\hat { Y }$ = 32 - 2X, where X is the number of complaints each quarter about a service man and Y is the number of months of employment. -Refer to Data Set 6-5. The correlation coefficient of the data would be