Question 1

If the correlation coefficient is 0.790, what is the explained variation?

Accepted Answer

A)  37.6% 
B)  79% 
C)  21% 
D)  62.4% 
A)  37.6% 
B)  79% 
C)  21% 
D)  62.4%

Question 2

The population correlation coefficient is computed by using all possible pairs of data values $( x , y )$ taken from a population.

Accepted Answer

A) True 
 B)False

Question 3

$$\text { A regression line was calculated as } y ^ { \prime } = 9.7 - 3.2 x \text {. The slope of this line is } - 3.2 \text {. }$$

Accepted Answer

A) True 
 B)False

Question 4

For a prediction value of $y ^ { \prime }$ from a specific value $x$, which of the following contribute to the prediction error?

Accepted Answer

A)  The error in estimating the slope 
B)  The standard error of the estimate 
C)  The error in estimating the intercept 
D)  All of the above 
A)  The error in estimating the slope 
B)  The standard error of the estimate 
C)  The error in estimating the intercept 
D)  All of the above

Question 5

A multiple regression line was calculated in which $x _ { 1 }$ was a student's grade point average and $x _ { 2 }$ was a student's age. The multiple regression line was calculated as $y ^ { \prime } = - 18.7 + 46.3 x _ { 1 } + 7.28 x _ { 2 }$. If a student has a grade point average of $5.9$ and is 20 years old, what is the predicted value of $y ^ { \prime }$ ?

Accepted Answer

A)  400.1 
B)  387.2 
C)  421.6 
D)  615.5 
A)  400.1 
B)  387.2 
C)  421.6 
D)  615.5

Question 6

A realtor wanted to determine if there was a relationship between the size (in 100 square feet) of a new custom-built home and the price (in thousands of dollars) of home.
a. Draw a scatter plot.
b. Determine the regression line equation and plot the regression line on the scatter plot.
$\begin{array} { c c } \text { Size, } \boldsymbol { x } & \text { Price, } \boldsymbol { y } \ 26 & 235 \ 27 & 273 \ 41 & 387 \ 29 & 253 \ 33 & 295 \ 34 & 335 \ 36 & 395 \ 45 & 475 \ 22 & 203 \end{array}$

Accepted Answer

The answer of A realtor wanted to determine if there...

Question 7

A positive relationship exists when both variables increase or decrease at the same time.

Accepted Answer

A) True 
 B)False

Question 8

Number of fires and number of acres burned are as follows:
$\begin{array} { c r } \text { Fires } x & \text { Acres } \ 72 & 62 \ 69 & 42 \ 58 & 19 \ 47 & 26 \ 84 & 51 \ 62 & 15 \ 57 & 30 \ 45 & 15 \end{array}$
Predict the number of acres burned if $x = 60$ fires.

Accepted Answer

A)  $y ^ { \prime } = - 31.46$ acres when $x = 60$ fires. 
B)  $y ^ { \prime } = 28.54$ acres when $x = 60$ fires. 
C)  $y ^ { \prime } = 1.036$ acres when $x = 60$ fires. 
D)  $y ^ { \prime } = 30.7$ acres when $x = 60$ fires. 
A)  $y ^ { \prime } = - 31.46$ acres when $x = 60$ fires. 
B)  $y ^ { \prime } = 28.54$ acres when $x = 60$ fires. 
C)  $y ^ { \prime } = 1.036$ acres when $x = 60$ fires. 
D)  $y ^ { \prime } = 30.7$ acres when $x = 60$ fires.

Question 9

A correlation coefficient $r$ was calculated to be $0.830$. The coefficient of nondetermination would be $0.170$.

Accepted Answer

A) True 
 B)False

Question 10

Test the significance of the correlation coefficient $r$ at $\alpha = 0.05$ for the data below.
$\begin{array} { l c c c c c } \text { X values } & 53 & 60 & 68 & 78 & 83 \ \text { Y values } & 81 & 86 & 91 & 97 & 104 \end{array}$

Accepted Answer

A) Reject $\rho = 0$ because $12.15 > 2.78$ B) Accept $\rho = 0$ because $12.47 3.18$ D) Accept $\rho = 0$ because $12.15 <$ A) Reject $\rho = 0$ because $12.15 > 2.78$ B) Accept $\rho = 0$ because $12.47 3.18$ D) Accept $\rho = 0$ because $12.15 <$

Question 11

A study was conducted to determine if there was a relationship between the prices a non-member of a book club paid for various publications and the prices that a member pa the same publications. The data gathered is shown below. Compute the value of the corre coefficient.
$\begin{array} { c c } \text { Non-member } & \text { Member } \ \text { Price } & \text { Price } \ 58 & 32 \ 42 & 22 \ 46 & 20 \ 32 & 16 \ 25 & 19 \ 75 & 58 \ 35 & 34 \ 63 & 48 \end{array}$

Accepted Answer

A)  0.932 
B)  0.679 
C)  0.857 
D)  0.762 
A)  0.932 
B)  0.679 
C)  0.857 
D)  0.762

Question 12

The following data list ages of cars (in years) and monthly repair cost in dollars. What is standard error of the estimate?
$\begin{array} { c c } \text { Age } & \text { Cost } \ 3 & 25 \ 5 & 35 \ 7 & 55 \ 9 & 50 \ 11 & 75 \ 14 & 85 \end{array}$

Accepted Answer

A)  6.36 
B)  8.75 
C)  7.34 
D)  5.49 
A)  6.36 
B)  8.75 
C)  7.34 
D)  5.49

Question 13

An analysis results in a multiple regression equation of $y ^ { \prime } = 68 + 27 x _ { 1 } + 2 x _ { 2 }$. We can conclude that

Accepted Answer

A)  The variable $x _ { 1 }$ is not a significant factor in this model. 
B)  This is insufficient information to assess the significance of $x _ { 1 }$. 
C)  The variable $x _ { 1 }$ is a moderately significant factor in this model. 
D)  The variable $x _ { 1 }$ is a very significant factor in this model. 
A)  The variable $x _ { 1 }$ is not a significant factor in this model. 
B)  This is insufficient information to assess the significance of $x _ { 1 }$. 
C)  The variable $x _ { 1 }$ is a moderately significant factor in this model. 
D)  The variable $x _ { 1 }$ is a very significant factor in this model.

Question 14

The standard error of estimate is the square root of the unexplained variation.

Accepted Answer

A) True 
 B)False

Question 15

A study was conducted to determine if there was a linear relationship between a po age and his/her peak heart rate.
a. Draw the scatter plot for the variables.
b. Give a brief explanation of the type of relationship.
$\begin{array} { c c } \text { Age } & \text { Peak Heart Rate } \ 16 & 220 \ 26 & 194 \ 32 & 193 \ 37 & 178 \ 42 & 172 \ 53 & 160 \ 48 & 174 \ 21 & 214 \end{array}$

Accepted Answer

a.
@#IMG-DLM&

b. There appear

Question 16

Using a regression line of $y ^ { \prime } = 17.3 + 3.4 x$, a value of $x = 3.6$ would result in a predicted value of $y ^ { \prime } = 31.7$.

Accepted Answer

A) True 
 B)False

Question 17

The rounding rule for the correlation coefficient requires two decimal places.

Accepted Answer

A) True 
 B)False

Question 18

If the correlation coefficient is 0.930, what is the unexplained variation?

Accepted Answer

A)  86.5% 
B)  7% 
C)  93% 
D)  13.5% 
A)  86.5% 
B)  7% 
C)  93% 
D)  13.5%

Question 19

$$\text { The symbol used for the multiple correlation coefficient is } R \text {. }$$

Accepted Answer

A) True 
 B)False

Question 20

Ten pairs of points yielded a correlation coefficient $r$ of $0.790$. If $\alpha = 0.05$, which of the following statements is correct if $H _ { 0 } : \rho = 0$ ? (Do not calculate a $t$-value.)

Accepted Answer

A)  Because 0.790 is greater than 0.602, the null hypothesis is not rejected. 
B)  There is no correlation between the variables. 
C)  Because 0.790 is greater than 0.632, the null hypothesis is rejected. 
D)  Because 0.790 is greater than 0.632, the null hypothesis is not rejected. 
A)  Because 0.790 is greater than 0.602, the null hypothesis is not rejected. 
B)  There is no correlation between the variables. 
C)  Because 0.790 is greater than 0.632, the null hypothesis is rejected. 
D)  Because 0.790 is greater than 0.632, the null hypothesis is not rejected.

If the correlation coefficient is 0.790, what is the explained variation?

The population correlation coefficient is computed by using all possible pairs of data values $( x , y )$ taken from a population.

$\text { A regression line was calculated as } y ^ { \prime } = 9.7 - 3.2 x \text {. The slope of this line is } - 3.2 \text {. }$

For a prediction value of $y ^ { \prime }$ from a specific value $x$ , which of the following contribute to the prediction error?

A positive relationship exists when both variables increase or decrease at the same time.

Number of fires and number of acres burned are as follows: Fires x Acres 72 62 69 42 58 19 47 26 84 51 62 15 57 30 45 15 Predict the number of acres burned if $x = 60$ fires.

A correlation coefficient $r$ was calculated to be $0.830$ . The coefficient of nondetermination would be $0.170$ .

Test the significance of the correlation coefficient $r$ at $\alpha = 0.05$ for the data below. X values 53 60 68 78 83 Y values 81 86 91 97 104

The following data list ages of cars (in years) and monthly repair cost in dollars. What is standard error of the estimate? Age Cost 3 25 5 35 7 55 9 50 11 75 14 85

An analysis results in a multiple regression equation of $y ^ { \prime } = 68 + 27 x _ { 1 } + 2 x _ { 2 }$ . We can conclude that

The standard error of estimate is the square root of the unexplained variation.

A study was conducted to determine if there was a linear relationship between a po age and his/her peak heart rate. a. Draw the scatter plot for the variables. b. Give a brief explanation of the type of relationship. Age Peak Heart Rate 16 220 26 194 32 193 37 178 42 172 53 160 48 174 21 214

Using a regression line of $y ^ { \prime } = 17.3 + 3.4 x$ , a value of $x = 3.6$ would result in a predicted value of $y ^ { \prime } = 31.7$ .

The rounding rule for the correlation coefficient requires two decimal places.

If the correlation coefficient is 0.930, what is the unexplained variation?

$\text { The symbol used for the multiple correlation coefficient is } R \text {. }$

Ten pairs of points yielded a correlation coefficient $r$ of $0.790$ . If $\alpha = 0.05$ , which of the following statements is correct if $H _ { 0 } : \rho = 0$ ? (Do not calculate a $t$ -value.)

The Nature of Probability and Statistics

Frequency Distributions and Graphs

Data Description

Probability and Counting Rules

Discrete Probability Distributions

The Normal Distribution

Confidence Intervals and Sample Size

Hypothesis Testing

Testing the Difference Between Two Means, Two Variances, and Two Proportions

Other Chi-Square Tests

Analysis of Variance

Nonparametric Statistics

Sampling and Simulation

Filters

Exam 10: Correlation and Regression

If the correlation coefficient is 0.790, what is the explained variation?

The population correlation coefficient is computed by using all possible pairs of data values (x,y)( x , y )(x,y) taken from a population.

For a prediction value of y′y ^ { \prime }y′ from a specific value xxx , which of the following contribute to the prediction error?

A positive relationship exists when both variables increase or decrease at the same time.

Number of fires and number of acres burned are as follows: Fires x Acres 72 62 69 42 58 19 47 26 84 51 62 15 57 30 45 15 Predict the number of acres burned if x=60x = 60x=60 fires.

A correlation coefficient rrr was calculated to be 0.8300.8300.830 . The coefficient of nondetermination would be 0.1700.1700.170 .

Test the significance of the correlation coefficient rrr at α=0.05\alpha = 0.05α=0.05 for the data below. X values 53 60 68 78 83 Y values 81 86 91 97 104

The following data list ages of cars (in years) and monthly repair cost in dollars. What is standard error of the estimate? Age Cost 3 25 5 35 7 55 9 50 11 75 14 85

An analysis results in a multiple regression equation of y′=68+27x1+2x2y ^ { \prime } = 68 + 27 x _ { 1 } + 2 x _ { 2 }y′=68+27x1​+2x2​ . We can conclude that

The standard error of estimate is the square root of the unexplained variation.

A study was conducted to determine if there was a linear relationship between a po age and his/her peak heart rate. a. Draw the scatter plot for the variables. b. Give a brief explanation of the type of relationship. Age Peak Heart Rate 16 220 26 194 32 193 37 178 42 172 53 160 48 174 21 214

Using a regression line of y′=17.3+3.4xy ^ { \prime } = 17.3 + 3.4 xy′=17.3+3.4x , a value of x=3.6x = 3.6x=3.6 would result in a predicted value of y′=31.7y ^ { \prime } = 31.7y′=31.7 .

The rounding rule for the correlation coefficient requires two decimal places.

If the correlation coefficient is 0.930, what is the unexplained variation?

The symbol used for the multiple correlation coefficient is R. \text { The symbol used for the multiple correlation coefficient is } R \text {. } The symbol used for the multiple correlation coefficient is R.

Ten pairs of points yielded a correlation coefficient rrr of 0.7900.7900.790 . If α=0.05\alpha = 0.05α=0.05 , which of the following statements is correct if H0:ρ=0H _ { 0 } : \rho = 0H0​:ρ=0 ? (Do not calculate a ttt -value.)

The Nature of Probability and Statistics

Frequency Distributions and Graphs

Data Description

Probability and Counting Rules

Discrete Probability Distributions

The Normal Distribution

Confidence Intervals and Sample Size

Hypothesis Testing

Testing the Difference Between Two Means, Two Variances, and Two Proportions

Other Chi-Square Tests

Analysis of Variance

Nonparametric Statistics

Sampling and Simulation

Filters

The population correlation coefficient is computed by using all possible pairs of data values $( x , y )$ taken from a population.

For a prediction value of $y ^ { \prime }$ from a specific value $x$ , which of the following contribute to the prediction error?

Number of fires and number of acres burned are as follows: Fires x Acres 72 62 69 42 58 19 47 26 84 51 62 15 57 30 45 15 Predict the number of acres burned if $x = 60$ fires.

A correlation coefficient $r$ was calculated to be $0.830$ . The coefficient of nondetermination would be $0.170$ .

Test the significance of the correlation coefficient $r$ at $\alpha = 0.05$ for the data below. X values 53 60 68 78 83 Y values 81 86 91 97 104

An analysis results in a multiple regression equation of $y ^ { \prime } = 68 + 27 x _ { 1 } + 2 x _ { 2 }$ . We can conclude that

Using a regression line of $y ^ { \prime } = 17.3 + 3.4 x$ , a value of $x = 3.6$ would result in a predicted value of $y ^ { \prime } = 31.7$ .

$\text { The symbol used for the multiple correlation coefficient is } R \text {. }$

Ten pairs of points yielded a correlation coefficient $r$ of $0.790$ . If $\alpha = 0.05$ , which of the following statements is correct if $H _ { 0 } : \rho = 0$ ? (Do not calculate a $t$ -value.)