Question 1

Suppose the regression line for a scatterplot passes through the points (0, 10) and (5, 20). What type of association exists between the variables?

Accepted Answer

a positive association

Question 2

The least-squares regression line is the "best" line in that it minimizes a certain sum. What is this sum?

Accepted Answer

The sum of the squares of the vertical distances from each data point to the line

Question 3

A Little League manager keeps a record book showing the statistics for his players. The first few lines of the record book show: $$\begin{array} { l l l l } 
\text { Player } & \text { At Bats } & \text { Hits } & \text { Average } \
\text { Brett } & 142 & 37 & .261 \
\text { Mike } & 128 & 32 & .250 \
\text { Carlos } & 128 & 35 & .273 \
\text { John } & 123 & 36 & .293
\end{array}$$ What are the individuals and the variables in these data?

Accepted Answer

The individuals are the players. The variables are at bats, hits, and average.

Question 4

Use the following data to answer the Questions: $\begin{array} { r r } 
\underline { X }  & \underline { Y } \
66 & 118 \
50 & 99 \
73 & 120 \
69 & 121 \
72 & 123 \
65 & 108 \
62 & 111
\end{array}$
-Does the data have an outlier?

Accepted Answer

The point (50, 99) a

Question 5

Suppose the regression line for a scatterplot passes through the points (0, 30) and (5, 20). What type of association exists between the variables?

Accepted Answer

a negative

Question 6

If two variables are negatively associated, then the regression line:

Accepted Answer

A)  has a negative intercept. 
B)  has a negative slope. 
C)  has negative coefficients. 
D)  is valid for only negative values. 
A)  has a negative intercept. 
B)  has a negative slope. 
C)  has negative coefficients. 
D)  is valid for only negative values.

Question 7

Suppose you are taking a survey of young children. If you measure their height and their weight, what do you expect to determine about these data?

Accepted Answer

A)  There is no correlation between the data. 
B)  There is a positive correlation between the data. 
C) There is a negative correlation between the data. 
D) There is both a negative and a positive correlation between the data. 
A)  There is no correlation between the data. 
B)  There is a positive correlation between the data. 
C) There is a negative correlation between the data. 
D) There is both a negative and a positive correlation between the data.

Question 8

Suppose the equation for a regression line is y = 4x + 6. If x = 5, what is the predicted corresponding value for y?

Accepted Answer

The answer of Suppose the equation for a regression line...

Question 9

Use the following Table to answer the  Questions: $\begin{array} { | l | c | c | c | c | c | c | c | } 
\hline \begin{array} { l } 
\text { Hours spent } \
\text { partying per } \
\text { week } ( x )
\end{array} & 10 & 40 & 0 & 5 & 60 & 20 & 12 \
\hline \text { GPA } ( y ) & 3.4 & 0.5 & 3.9 & 3.7 & 4.0 & 1.3 & 3.1 \
\hline
\end{array}$
-If you remove the student who parties 60 hours per week from the data set, what is the correlation?

Accepted Answer

The answer of Use the following Table to answer the...

Question 10

Use the following data set to answer the  Questions:  $\begin{array} { | l | l | l | l | l | l | l | l | l } 
\hline \begin{array} { l } 
\text { Length of } \
\text { commute in } \
\text { miles } ( x )
\end{array} & 2 & 10 & 8 & 30 & 12 & 70 & 15 & 20 \
\hline \begin{array} { l } 
\text { Time of } \
\text { commute in } \
\text { minutes (y) }
\end{array} & 5 & 25 & 20 & 45 & 25 & 80 & 30 & 35 \
\hline
\end{array}$
-According to the regression equation, what is the expected length in minutes of a 25-mile commute?

Accepted Answer

A)  30 
B)  37 
C)  42 
D)  50 
A)  30 
B)  37 
C)  42 
D)  50

Question 11

If you do not study, on average what test score would you expect?

Accepted Answer

A)  about 43 
B)  about 46 
C)  about 48 
D)  None of the above. 
A)  about 43 
B)  about 46 
C)  about 48 
D)  None of the above.

Question 12

Use the following data set to answer the  Questions:  $\begin{array} { | l | l | l | l | l | l | l | l | l } 
\hline \begin{array} { l } 
\text { Length of } \
\text { commute in } \
\text { miles } ( x )
\end{array} & 2 & 10 & 8 & 30 & 12 & 70 & 15 & 20 \
\hline \begin{array} { l } 
\text { Time of } \
\text { commute in } \
\text { minutes (y) }
\end{array} & 5 & 25 & 20 & 45 & 25 & 80 & 30 & 35 \
\hline
\end{array}$
-What is the correlation between the variables?

Accepted Answer

A)  $- 1$ 
B)  0.11 
C)  0.95 
D)  0.98 
A)  $- 1$ 
B)  0.11 
C)  0.95 
D)  0.98

Question 13

Use the following Table to answer the  Questions: $\begin{array} { | l | c | c | c | c | c | c | c | } 
\hline \begin{array} { l } 
\text { Hours spent } \
\text { partying per } \
\text { week } ( x )
\end{array} & 10 & 40 & 0 & 5 & 60 & 20 & 12 \
\hline \text { GPA } ( y ) & 3.4 & 0.5 & 3.9 & 3.7 & 4.0 & 1.3 & 3.1 \
\hline
\end{array}$
-What is the y-intercept of the regression line?

Accepted Answer

The answer of Use the following Table to answer the...

Question 14

If a regression line for two variables has a small positive slope, then:

Accepted Answer

A)  the variables are positively associated. 
B)  the variables are negatively associated. 
C)  the association of the variables cannot be determined. 
D)  the variables have no association with each other. 
A)  the variables are positively associated. 
B)  the variables are negatively associated. 
C)  the association of the variables cannot be determined. 
D)  the variables have no association with each other.

Question 15

Ten crickets were observed under various temperatures and the number of chirps each cricket made per second was recorded. The results are shown in the table below. $\begin{array} { l l l l l l l l l l l } 
\text { Temperature in degrees F } & 70 & 72 & 74 & 75 & 81 & 82 & 83 & 84 & 89 & 93 \
\text { Chirps per second } & 15 & 15 & 15 & 16 & 17 & 17 & 16 & 17 & 19 & 20
\end{array}$ Make a scatterplot. Is the association between these variables positive or negative?

Accepted Answer

The associ

Question 16

Suppose the equation for a regression line is y = 4x + 6. If y = 12, what is the predicted corresponding value for x?

Accepted Answer

The answer of Suppose the equation for a regression line...

Question 17

According to the regression equation, what is the expected test score if three hours are spent studying?

Accepted Answer

A)  about 63 
B)  about 65 
C)  about 67 
D)  about 70 
A)  about 63 
B)  about 65 
C)  about 67 
D)  about 70

Question 18

Below are data on the age of 10 cars and the amount of money spent on auto repairs in one year. Make a scatterplot of the data. $$\text { Age (years) Autorepairs (\$) }$$ $$\begin{array} { r r } 
2 & 120 \
3 & 175 \
3 & 160 \
5 & 250 \
6 & 325 \
7 & 380 \
10 & 500 \
12 & 615 \
12 & 630 \
15 & 770
\end{array}$$

Accepted Answer

The answer of Below are data on the age of...

Question 19

While you are running on a treadmill, you would expect a positive correlation between:

Accepted Answer

A)  time you spend and calories you will burn. 
B)  time you spend and your weight. 
C) Time you spend and average running speed. 
D) None of the above. 
A)  time you spend and calories you will burn. 
B)  time you spend and your weight. 
C) Time you spend and average running speed. 
D) None of the above.

Question 20

Use the following Table to answer the  Questions: $\begin{array} { | l | c | c | c | c | c | c | c | } 
\hline \begin{array} { l } 
\text { Hours spent } \
\text { partying per } \
\text { week } ( x )
\end{array} & 10 & 40 & 0 & 5 & 60 & 20 & 12 \
\hline \text { GPA } ( y ) & 3.4 & 0.5 & 3.9 & 3.7 & 4.0 & 1.3 & 3.1 \
\hline
\end{array}$
-Which student in this data set is an outlier?

Accepted Answer

The student who part

Exam 6: Exploring Data: Relationships

Suppose the regression line for a scatterplot passes through the points (0, 10) and (5, 20). What type of association exists between the variables?

The least-squares regression line is the "best" line in that it minimizes a certain sum. What is this sum?

A Little League manager keeps a record book showing the statistics for his players. The first few lines of the record book show: Player At Bats Hits Average Brett 142 37 .261 Mike 128 32 .250 Carlos 128 35 .273 John 123 36 .293 What are the individuals and the variables in these data?

Use the following data to answer the Questions: 66 118 50 99 73 120 69 121 72 123 65 108 62 111 -Does the data have an outlier?

Suppose the regression line for a scatterplot passes through the points (0, 30) and (5, 20). What type of association exists between the variables?

If two variables are negatively associated, then the regression line:

Suppose you are taking a survey of young children. If you measure their height and their weight, what do you expect to determine about these data?

Suppose the equation for a regression line is y = 4x + 6. If x = 5, what is the predicted corresponding value for y?

Use the following Table to answer the Questions: Hours spent partying per week (x) 10 40 0 5 60 20 12 GPA (y) 3.4 0.5 3.9 3.7 4.0 1.3 3.1 -If you remove the student who parties 60 hours per week from the data set, what is the correlation?

Use the following data set to answer the Questions: Length of commute in miles (x) 2 10 8 30 12 70 15 20 Time of commute in minutes (y) 5 25 20 45 25 80 30 35 -According to the regression equation, what is the expected length in minutes of a 25-mile commute?

If you do not study, on average what test score would you expect?

Use the following data set to answer the Questions: Length of commute in miles (x) 2 10 8 30 12 70 15 20 Time of commute in minutes (y) 5 25 20 45 25 80 30 35 -What is the correlation between the variables?

Use the following Table to answer the Questions: Hours spent partying per week (x) 10 40 0 5 60 20 12 GPA (y) 3.4 0.5 3.9 3.7 4.0 1.3 3.1 -What is the y-intercept of the regression line?

If a regression line for two variables has a small positive slope, then:

Suppose the equation for a regression line is y = 4x + 6. If y = 12, what is the predicted corresponding value for x?

According to the regression equation, what is the expected test score if three hours are spent studying?

Below are data on the age of 10 cars and the amount of money spent on auto repairs in one year. Make a scatterplot of the data. Age (years) Autorepairs ($) \text { Age (years) Autorepairs (\$) } Age (years) Autorepairs ($) 2 120 3 175 3 160 5 250 6 325 7 380 10 500 12 615 12 630 15 770

While you are running on a treadmill, you would expect a positive correlation between:

Use the following Table to answer the Questions: Hours spent partying per week (x) 10 40 0 5 60 20 12 GPA (y) 3.4 0.5 3.9 3.7 4.0 1.3 3.1 -Which student in this data set is an outlier?

Urban Services

Business Efficiency

Planning and Scheduling

Linear Programming

Exploring Data: Distributions

Data for Decisions

Probability: the Mathematics of Chance

Social Choice: the Impossible Dream

The Manipulability of Voting Systems

Weighted Voting Systems

Electing the President

Fair Division

Apportionment

Game Theory: the Mathematics of Competition

Identification Numbers

Information Science

Growth and Form

Symmetry and Patterns

Tilings

Savings Models

Borrowing Models

The Economics of Resources

Filters

Below are data on the age of 10 cars and the amount of money spent on auto repairs in one year. Make a scatterplot of the data. $\text { Age (years) Autorepairs (\$) }$ 2 120 3 175 3 160 5 250 6 325 7 380 10 500 12 615 12 630 15 770