Question 1

Which graph shows a pattern that would be appropriately described by the equation $\hat{y}$ = $b_{0}$ + $ b_{1}x$ ?

Accepted Answer

A)  
   
B)  
   
C)  
   
D)  
   
A)  
   
B)  
   
C)  
   
D)

Question 2

Which one of the following is a variable that we usually put on the horizontal axis of a scatterplot?

Accepted Answer

A)  y variable 
B)  explanatory variable 
C)  response variable 
D)  dependent variable 
A)  y variable 
B)  explanatory variable 
C)  response variable 
D)  dependent variable

Question 3

A scatterplot of geographic latitude (X) and average January temperature (Y) for 20 cities in the United States is given below. Is there a positive association or a negative association? Explain what such an association means in the context of this situation.

Accepted Answer

There is a negative associatio

Question 4

You wish to describe the relationship between exam grades and the amount of time students watch the Discovery Channel. The correlation turns out to be r = +0.30. What does this mean?

Accepted Answer

A)  The more a student watches the Discovery Channel, the higher his or her exam grades tend to be. 
B)  The more a student watches the Discovery Channel, the lower his or her exam grades tend to be. 
C)  In order to increase your exam grades, it is recommended that you spend more time watching the Discovery Channel. 
D)  30% of the variation in exam grades is explained by the linear relationship with time spent watching the Discovery Channel. 
A)  The more a student watches the Discovery Channel, the higher his or her exam grades tend to be. 
B)  The more a student watches the Discovery Channel, the lower his or her exam grades tend to be. 
C)  In order to increase your exam grades, it is recommended that you spend more time watching the Discovery Channel. 
D)  30% of the variation in exam grades is explained by the linear relationship with time spent watching the Discovery Channel.

Question 5

Use the following information for questions:
 Past data has shown that the regression line relating the final exam score and the midterm exam score for students who take statistics from a certain professor is:
final exam = 50 + 0.5 * midterm
-Which of the following gives a correct interpretation of the slope?

Accepted Answer

A)  A student who scored 0 on the midterm would be predicted to score 50 on the final exam. 
B)  A student who scored 0 on the final exam would be predicted to score 50 on the midterm exam. 
C)  A student who scored 2 points higher than another student on the midterm would be predicted to score 1 point higher than the other student on the final exam. 
D)  None of the interpretations above are correct interpretations of the slope. 
A)  A student who scored 0 on the midterm would be predicted to score 50 on the final exam. 
B)  A student who scored 0 on the final exam would be predicted to score 50 on the midterm exam. 
C)  A student who scored 2 points higher than another student on the midterm would be predicted to score 1 point higher than the other student on the final exam. 
D)  None of the interpretations above are correct interpretations of the slope.

Question 6

What are influential observations and where are they generally found?

Accepted Answer

Influential observations are g

Question 7

Use the following information for questions:
 The simple linear regression equation can be written as $\hat{y}$ = $b_{0}$ + $ b_{1}x$
-In the simple linear regression equation, the symbol $\hat{y}$ represents the

Accepted Answer

A)  average or predicted response. 
B)  estimated intercept. 
C)  estimated slope. 
D)  explanatory variable. 
A)  average or predicted response. 
B)  estimated intercept. 
C)  estimated slope. 
D)  explanatory variable.

Question 8

The scatterplot below shows students' heights (y) versus father's heights (x) for a sample of 173 college students. The symbol "+" represents a male student and the symbol "o" represents a female student. 
   A linear regression equation is determined for the relationship between female students' heights and their father's heights and, separately, one for male students and their fathers. How do the y-intercepts compare for these two regression equations?

Accepted Answer

The y-intercept for the female

Question 9

Use the following information for questions:
 A regression between foot length (response variable in cm) and height (explanatory variable in inches) for 33 students resulted in the following regression equation: $\hat{y}$ = 10.9 + 0.23x
-What is the estimated average foot length for students who are 70 inches tall?

Accepted Answer

A)  27 cm 
B)  28 cm 
C)  29 cm 
D)  30 cm 
A)  27 cm 
B)  28 cm 
C)  29 cm 
D)  30 cm

Question 10

Use the following information for questions:
 The following output is for a simple regression in which y = grade point average (GPA) and x = number of classes skipped in a typical week. The results were determined using self-reported data for a sample of n = 1,673 students at a large northeastern university.
  
-What is the predicted grade point average for a student who skips 4 classes per typical week?

Accepted Answer

The predic

Question 11

A psychology student wishes to determine the strength of the relationship between school grades and short term memory. Twenty-two students were given a memory test. SPSS was used to analyze the data. Part of the output is shown below. 
     What is the value of the correlation coefficient between grades and the memory test scores?

Accepted Answer

The slope is positiv

Question 12

A counselor at a weight-loss clinic wishes to determine if there is a relationship between BMI and depression. The scores of 6 patients are determined. She makes a scatterplot to assess of the relationship appears to be linear. It turns out to be a positive linear relationship. The Sum of Squared Errors is 8.875 and the Total Sum of Squares (SSTO) is 17.5. What is the value of the correlation coefficient between BMI and depression?

Accepted Answer

r² = (17.5

Question 13

The regression line for a set of points is given by $\hat{y}$ = 12 - 6x. What is the slope of the line?

Accepted Answer

A)  -12 
B) -6 
C)  +6 
D)  +12 
A)  -12 
B) -6 
C)  +6 
D)  +12

Question 14

Consider the following graph:   For these data, there is

Accepted Answer

A)  positive correlation. 
B)  negative correlation. 
C)  biased correlation. 
D)  zero correlation. 
A)  positive correlation. 
B)  negative correlation. 
C)  biased correlation. 
D)  zero correlation.

Question 15

In a certain study the relationship between (social) mobility of female foreign American residents and the number of years they have lived in the U.S. is examined. The researcher hopes to predict the mobility of these women based on their length of stay. Part of the SPSS output is shown below:   What is the correct regression equation for summarizing this linear relationship?

Accepted Answer

A)  $\hat{y}$ = -3.799 + 7.745 years 
B)  $\hat{y}$ = 7.745 + 0.778. years 
C)  $\hat{y}$ = -3.799 + 0.778 mobility 
D)  $\hat{y}$ = 7.745 + -3.799 mobility 
A)  $\hat{y}$ = -3.799 + 7.745 years 
B)  $\hat{y}$ = 7.745 + 0.778. years 
C)  $\hat{y}$ = -3.799 + 0.778 mobility 
D)  $\hat{y}$ = 7.745 + -3.799 mobility

Question 16

Suppose a study of employees at a large company found a negative correlation between weight and distance walked on an average day. Explain why a conclusion that walking reduces weight cannot be made from this study (i.e. What confounding variable could also explain the observed negative correlation?)

Accepted Answer

People who are already in shap

Question 17

Which of the following sets of variables is most likely to have a negative association?

Accepted Answer

A)  the height of the son and the height of the father 
B)  the age of the wife and the age of the husband 
C)  the age of the mother and the number of children in the family 
D)  the age of the mother and the ability to have children 
A)  the height of the son and the height of the father 
B)  the age of the wife and the age of the husband 
C)  the age of the mother and the number of children in the family 
D)  the age of the mother and the ability to have children

Question 18

A scatterplot of y = height and x = left forearm length (cm) for 55 college students is given below. Is there a positive association or a negative association? Explain what this association means in the context of this situation.

Accepted Answer

There is a positive associatio

Question 19

Use the following information for questions:
 The simple linear regression equation can be written as $\hat{y}$ = $b_{0}$ + $ b_{1}x$
-In the simple linear regression equation, the symbol x represents the

Accepted Answer

A)  estimated or predicted response. 
B)  estimated intercept. 
C)  estimated slope. 
D)  explanatory variable. 
A)  estimated or predicted response. 
B)  estimated intercept. 
C)  estimated slope. 
D)  explanatory variable.

Question 20

Describe the type of association shown in the scatterplot below:

Accepted Answer

A)  Positive linear association 
B)  Negative linear association 
C)  Positive curvilinear association 
D)  Negative curvilinear association 
A)  Positive linear association 
B)  Negative linear association 
C)  Positive curvilinear association 
D)  Negative curvilinear association

Which graph shows a pattern that would be appropriately described by the equation $\hat{y}$ = $b_{0}$ + $b_{1}x$ ?

Which one of the following is a variable that we usually put on the horizontal axis of a scatterplot?

A scatterplot of geographic latitude (X) and average January temperature (Y) for 20 cities in the United States is given below. Is there a positive association or a negative association? Explain what such an association means in the context of this situation.

You wish to describe the relationship between exam grades and the amount of time students watch the Discovery Channel. The correlation turns out to be r = +0.30. What does this mean?

What are influential observations and where are they generally found?

Use the following information for questions: The simple linear regression equation can be written as $\hat{y}$ = $b_{0}$ + $b_{1}x$ -In the simple linear regression equation, the symbol $\hat{y}$ represents the

The regression line for a set of points is given by $\hat{y}$ = 12 - 6x. What is the slope of the line?

Consider the following graph: For these data, there is

Which of the following sets of variables is most likely to have a negative association?

A scatterplot of y = height and x = left forearm length (cm) for 55 college students is given below. Is there a positive association or a negative association? Explain what this association means in the context of this situation.

Use the following information for questions: The simple linear regression equation can be written as $\hat{y}$ = $b_{0}$ + $b_{1}x$ -In the simple linear regression equation, the symbol x represents the

Describe the type of association shown in the scatterplot below:

Statistics Success Stories and Cautionary Tales

Turning Data Into Information

Relationships Between Categorical Variables

Sampling: Surveys and How to Ask Questions

Gathering Useful Data for Examining Relationships

Probability

Random Variables

Understanding Sampling Distributions: Statistics As Random Variables

Estimating Proportions With Confidence

Estimating Means With Confidence

Testing Hypotheses About Proportions

Testing Hypotheses About Means

Inference About Simple Regression

More About Inference for Categorical Variables

Analysis of Variance

Turning Information Into Wisdom

Filters

Exam 3: Relationships Between Quantitative Variables

Which graph shows a pattern that would be appropriately described by the equation y^\hat{y}y^​ = b0b_{0}b0​ + b1x b_{1}xb1​x ?

Which one of the following is a variable that we usually put on the horizontal axis of a scatterplot?

A scatterplot of geographic latitude (X) and average January temperature (Y) for 20 cities in the United States is given below. Is there a positive association or a negative association? Explain what such an association means in the context of this situation.

You wish to describe the relationship between exam grades and the amount of time students watch the Discovery Channel. The correlation turns out to be r = +0.30. What does this mean?

What are influential observations and where are they generally found?

Use the following information for questions: The simple linear regression equation can be written as y^\hat{y}y^​ = b0b_{0}b0​ + b1x b_{1}xb1​x -In the simple linear regression equation, the symbol y^\hat{y}y^​ represents the

The regression line for a set of points is given by y^\hat{y}y^​ = 12 - 6x. What is the slope of the line?

Consider the following graph: For these data, there is

Which of the following sets of variables is most likely to have a negative association?

A scatterplot of y = height and x = left forearm length (cm) for 55 college students is given below. Is there a positive association or a negative association? Explain what this association means in the context of this situation.

Use the following information for questions: The simple linear regression equation can be written as y^\hat{y}y^​ = b0b_{0}b0​ + b1x b_{1}xb1​x -In the simple linear regression equation, the symbol x represents the

Describe the type of association shown in the scatterplot below:

Statistics Success Stories and Cautionary Tales

Turning Data Into Information

Relationships Between Categorical Variables

Sampling: Surveys and How to Ask Questions

Gathering Useful Data for Examining Relationships

Probability

Random Variables

Understanding Sampling Distributions: Statistics As Random Variables

Estimating Proportions With Confidence

Estimating Means With Confidence

Testing Hypotheses About Proportions

Testing Hypotheses About Means

Inference About Simple Regression

More About Inference for Categorical Variables

Analysis of Variance

Turning Information Into Wisdom

Filters

Which graph shows a pattern that would be appropriately described by the equation $\hat{y}$ = $b_{0}$ + $b_{1}x$ ?

Use the following information for questions: The simple linear regression equation can be written as $\hat{y}$ = $b_{0}$ + $b_{1}x$ -In the simple linear regression equation, the symbol $\hat{y}$ represents the

The regression line for a set of points is given by $\hat{y}$ = 12 - 6x. What is the slope of the line?

Use the following information for questions: The simple linear regression equation can be written as $\hat{y}$ = $b_{0}$ + $b_{1}x$ -In the simple linear regression equation, the symbol x represents the