Question 1

If there is a strong negative linear relationship between the variables, the value of __________ will be
close to -1. 
________________________________________

Accepted Answer

r

Question 2

Using a regression line of $y ^ { \prime } = 17.3 + 34 x$ , a value of x = 3.6 would result in a predicted value of $y ^ { \prime } = 31.7$ .

Accepted Answer

A) True 
 B)False  False

Question 3

Ten pairs of points yielded a correlation coefficient $r$ of $0.79$. If $\alpha = 0.05$, which of the following statements is correct if $\mathrm { H } _ { 0 } : \rho = 0$ ? (Do not calculate a $t$-value.)

Accepted Answer

A)  Because $0.79$ is greater than $0.632$, the null hypothesis is not rejected. 
B)  Because $0.79$ is greater than $0.632$, the null hypothesis is rejected. 
C)  Because $0.79$ is greater than $0.602$, the null hypothesis is not rejected. 
D)  There is no correlation between the variables. 
A)  Because $0.79$ is greater than $0.632$, the null hypothesis is not rejected. 
B)  Because $0.79$ is greater than $0.632$, the null hypothesis is rejected. 
C)  Because $0.79$ is greater than $0.602$, the null hypothesis is not rejected. 
D)  There is no correlation between the variables. B

Question 4

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

Accepted Answer

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

Question 5

If the correlation coefficient r is equal to 0.48, find the coefficient of determination.

Accepted Answer

A)  0.77 
B)  0.69 
C)  0.36 
D)  0.23 
A)  0.77 
B)  0.69 
C)  0.36 
D)  0.23

Question 6

A regression line was calculated as $y ^ { \prime } = 9.7 - 32 x$ . The slope of this line is -3.2.

Accepted Answer

A) True 
 B)False

Question 7

If $r = - 0.879$ and $n = 6$, test the significance of the correlation coefficient at $\neq = .05$

Accepted Answer

A)  Accept $- = 0$ because $4.20  2.78$ 
C)  Accept $- = 0$ because $- 3.69  2.54$ 
A)  Accept $- = 0$ because $4.20  2.78$ 
C)  Accept $- = 0$ because $- 3.69  2.54$

Question 8

If there are three independent variables $X _ { 1 } , X _ { 2 } , X _ { 3 }$ available, then the value of $R ^ { 2 }$ for a multiple regression of $y$ using $X _ { 1 } , X _ { 2 } , X _ { 3 }$ will always be smaller than the value of $r ^ { 2 }$ for a multiple regression of $y$ using just $X _ { 1 }$.

Accepted Answer

A) True 
 B)False

Question 9

Compute the correlation coefficient for the data below 
$\begin{array}{|c|c|c|c|c|c|}
\hline \text { X values } & -5 & -2 & 6 & 11 & 12 \
\hline \text { Y values } & 3 & 2 & -4 & 3 & -2 \
\hline
\end{array}$

Accepted Answer

A)  0.661 
B)  -0.437 
C)  0.467 
D)  -0.135 
A)  0.661 
B)  -0.437 
C)  0.467 
D)  -0.135

Question 10

A regression line can be used to show trends in data.

Accepted Answer

A) True 
 B)False

Question 11

An analysis results in a multiple regression equation of $y ^ { \prime } = 93 + 23 x _ { 1 } + 4 x _ { 2 }$ We can conclude that

Accepted Answer

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

Question 12

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 13

The symbol used for the multiple correlation coefficient is R.

Accepted Answer

A) True 
 B)False

Question 14

A study was conducted to determine if there was a relationship between the prices a non-member of a club paid for various publications and the prices that a member paid for the same publications. The data collected is shown below. Determine the value of

$\sum x y$      $\begin{array}{lc}
\text { Non-member } & \text { Membel } \
\text { Price, } x & \text { Price, } y \
58 & 32 \
42 & 22 \
46 & 20 \
32 & 16 \
25 & 19 \
75 & 58 \
35 & 34 \
63 & 48
\end{array}$

Accepted Answer

A)  13,251 
B)  93,624 
C)  19,712 
D)  9349 
A)  13,251 
B)  93,624 
C)  19,712 
D)  9349

Question 15

Compute the standard error of the estimate for the data below 
$\begin{array}{lccccc}
\mathrm{X} \text { values } & -3 & -2 & 4 & 6 & 8 \
\text { Y values } & 3 & 6 & -1 & 0 & -3
\end{array}$

Accepted Answer

A)  0.66 
B)  1.02 
C)  1.49 
D)  1.79 
A)  0.66 
B)  1.02 
C)  1.49 
D)  1.79

Question 16

The standard error of estimate is the standard deviation of the observed x-values about the predicted   values.

Accepted Answer

A) True 
 B)False

Question 17

The range of the correlation coefficient is from 0 to 1.

Accepted Answer

A) True 
 B)False

Question 18

If the equation for the regression line is y = 7x - 6, then a value of x = 3 will result in a predicted value for y of

Accepted Answer

A)  13 
B)  25 
C)  27 
D)  15 
A)  13 
B)  25 
C)  27 
D)  15

Question 19

With enough variables, it is possible to get an $\mathrm { R } ^ { 2 }$ value close to 1, even if the variables have no particular
meaning in the model.

Accepted Answer

A) True 
 B)False

Question 20

What is the value of $y ^ { \prime }$ when x = 3, if the equation of the regression line is $$y ^ { \prime } = 23.1 - 3.8 x ?$$

Accepted Answer

A)  4.73 
B)  5.29 
C)  34.5 
D)  11.7 
A)  4.73 
B)  5.29 
C)  34.5 
D)  11.7

If there is a strong negative linear relationship between the variables, the value of will be close to -1. ______________________________

Using a regression line of $y ^ { \prime } = 17.3 + 34 x$ , a value of x = 3.6 would result in a predicted value of $y ^ { \prime } = 31.7$ .

Ten pairs of points yielded a correlation coefficient $r$ of $0.79$ . If $\alpha = 0.05$ , which of the following statements is correct if $\mathrm { H } _ { 0 } : \rho = 0$ ? (Do not calculate a $t$ -value.)

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

If the correlation coefficient r is equal to 0.48, find the coefficient of determination.

A regression line was calculated as $y ^ { \prime } = 9.7 - 32 x$ . The slope of this line is -3.2.

If $r = - 0.879$ and $n = 6$ , test the significance of the correlation coefficient at $\neq = .05$

Compute the correlation coefficient for the data below X values -5 -2 6 11 12 Y values 3 2 -4 3 -2

A regression line can be used to show trends in data.

An analysis results in a multiple regression equation of $y ^ { \prime } = 93 + 23 x _ { 1 } + 4 x _ { 2 }$ We can conclude that

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

The symbol used for the multiple correlation coefficient is R.

Compute the standard error of the estimate for the data below values -3 -2 4 6 8 Y values 3 6 -1 0 -3

The standard error of estimate is the standard deviation of the observed x-values about the predicted values.

The range of the correlation coefficient is from 0 to 1.

If the equation for the regression line is y = 7x - 6, then a value of x = 3 will result in a predicted value for y of

With enough variables, it is possible to get an $\mathrm { R } ^ { 2 }$ value close to 1, even if the variables have no particular meaning in the model.

What is the value of $y ^ { \prime }$ when x = 3, if the equation of the regression line is $y ^ { \prime } = 23.1 - 3.8 x ?$

The Nature of Probability and Statistics

Frequency Distributions and Graphs

Data Description

Discrete Probability Distributions

The Normal Distribution

Confidence Intervals and Sample Size

Hypothesis Testing

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

Chi-Square and Analysis of Variance Anova

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Exam 9: Correlation and Regression

If there is a strong negative linear relationship between the variables, the value of __________ will be close to -1. ________________________________________

Using a regression line of y′=17.3+34xy ^ { \prime } = 17.3 + 34 xy′=17.3+34x , a value of x = 3.6 would result in a predicted value of y′=31.7y ^ { \prime } = 31.7y′=31.7 .

Ten pairs of points yielded a correlation coefficient rrr of 0.790.790.79 . If α=0.05\alpha = 0.05α=0.05 , which of the following statements is correct if H0:ρ=0\mathrm { H } _ { 0 } : \rho = 0H0​:ρ=0 ? (Do not calculate a ttt -value.)

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

If the correlation coefficient r is equal to 0.48, find the coefficient of determination.

A regression line was calculated as y′=9.7−32xy ^ { \prime } = 9.7 - 32 xy′=9.7−32x . The slope of this line is -3.2.

If r=−0.879r = - 0.879r=−0.879 and n=6n = 6n=6 , test the significance of the correlation coefficient at ≠=.05\neq = .05==.05

Compute the correlation coefficient for the data below X values -5 -2 6 11 12 Y values 3 2 -4 3 -2

A regression line can be used to show trends in data.

An analysis results in a multiple regression equation of y′=93+23x1+4x2y ^ { \prime } = 93 + 23 x _ { 1 } + 4 x _ { 2 }y′=93+23x1​+4x2​ We can conclude that

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

The symbol used for the multiple correlation coefficient is R.

Compute the standard error of the estimate for the data below values -3 -2 4 6 8 Y values 3 6 -1 0 -3

The standard error of estimate is the standard deviation of the observed x-values about the predicted values.

The range of the correlation coefficient is from 0 to 1.

If the equation for the regression line is y = 7x - 6, then a value of x = 3 will result in a predicted value for y of

With enough variables, it is possible to get an R2\mathrm { R } ^ { 2 }R2 value close to 1, even if the variables have no particular meaning in the model.

What is the value of y′y ^ { \prime }y′ when x = 3, if the equation of the regression line is y′=23.1−3.8x?y ^ { \prime } = 23.1 - 3.8 x ?y′=23.1−3.8x?

The Nature of Probability and Statistics

Frequency Distributions and Graphs

Data Description

Discrete Probability Distributions

The Normal Distribution

Confidence Intervals and Sample Size

Hypothesis Testing

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

Chi-Square and Analysis of Variance Anova

Tables

Data Bank

Glossary

Filters

If there is a strong negative linear relationship between the variables, the value of will be close to -1. ______________________________

Using a regression line of $y ^ { \prime } = 17.3 + 34 x$ , a value of x = 3.6 would result in a predicted value of $y ^ { \prime } = 31.7$ .

Ten pairs of points yielded a correlation coefficient $r$ of $0.79$ . If $\alpha = 0.05$ , which of the following statements is correct if $\mathrm { H } _ { 0 } : \rho = 0$ ? (Do not calculate a $t$ -value.)

A regression line was calculated as $y ^ { \prime } = 9.7 - 32 x$ . The slope of this line is -3.2.

If $r = - 0.879$ and $n = 6$ , test the significance of the correlation coefficient at $\neq = .05$

An analysis results in a multiple regression equation of $y ^ { \prime } = 93 + 23 x _ { 1 } + 4 x _ { 2 }$ We can conclude that

With enough variables, it is possible to get an $\mathrm { R } ^ { 2 }$ value close to 1, even if the variables have no particular meaning in the model.

What is the value of $y ^ { \prime }$ when x = 3, if the equation of the regression line is $y ^ { \prime } = 23.1 - 3.8 x ?$