Statistics salkind 4e test bank ch16

Chapter 16: Predicting Who’ll Win the Super Bowl: Using Linear Regression
Test Bank
MULTIPLE CHOICE
1. What can be used as the basis for prediction?
a. t-test
b. Correlation
c. F-test
d. Cohen’s d
ANS:
REF:
OBJ:
COG:

B
PTS: 1
DIF: Easy
What Is Prediction All About?
How prediction works and how it can be used in the social and behavioral sciences
Knowledge

2. What statistical technique is used to make predictions of future outcomes based on present

data?
a. Analysis of variance
b. Repeated measures
c. Linear regression
d. Correlational analysis
ANS:
REF:
OBJ:
COG:

C
PTS: 1
DIF: Easy
What Is Prediction All About?
How and why linear regression works when predicting one variable from another
Knowledge

3. Which of the following is used to illustrate the “best guess” as to the predicted Y variable

score based on X?
a. Regression equation
b. Scatter plot
c. Standard error of the estimate
d. Regression line
ANS: D
PTS: 1
DIF: Medium
REF: The Logic of Prediction
OBJ: How and why linear regression works when predicting one variable from another
COG: Knowledge
4. More accurate predictions are associated with
a. Correlations having higher absolute values
b. Correlations having lower absolute values
c. Correlations having higher values
d. Correlations having lower values
ANS: A

PTS: 1

DIF: Medium


REF: What Is Prediction All About?
COG: Comprehension

OBJ: How to judge the accuracy of predictions

5. When computing a predicted value, you first
a. Add the slope to the value of the independent variable
b. Multiply the slope by the value of the independent variable
c. Add the constant to the value of the independent variable
d. Subtract the constant from the value of the independent variable
ANS:
REF:
OBJ:
COG:

B
PTS: 1
DIF: Medium
Drawing the World’s Best Line (for Your Data)
How and why linear regression works when predicting one variable from another
Comprehension

6. When computing a predicted value, your second step is to
a. Multiply the slope by the independent variable
b. Add the slope to the independent variable
c. Add the intercept, or a, to the value of step one
d. Subtract the constant

ANS:
REF:
OBJ:
COG:

C
PTS: 1
DIF: Medium
Drawing the World’s Best Line (for Your Data)
How and why linear regression works when predicting one variable from another
Comprehension

7. If the absolute value of your correlation coefficient is 1, your error in prediction will be

_______.
a. Very high
b. 1
c. 0
d. Unknown
ANS: C
PTS: 1
REF: How Good Is Our Prediction?
COG: Comprehension

DIF: Medium
OBJ: How to judge the accuracy of predictions

8. If the absolute value of your correlation is very close to 0, your error in prediction will be

_______.

a. High
b. Low
c. Very low
d. 0
ANS: A
PTS: 1
REF: How Good Is Our Prediction?
COG: Comprehension

DIF: Medium
OBJ: How to judge the accuracy of predictions


9. To predict one variable from another, you must first
a. Compute the mean
b. Compute the standard deviation
c. Compute the correlation
d. Compute the variance
ANS:
REF:
OBJ:
COG:

C
PTS: 1
DIF: Medium
Drawing the World’s Best Line (for Your Data)
How and why linear regression works when predicting one variable from another
Comprehension

10. In a scatter plot, if all data points were aligned along a 45° angle, your correlation would be

_______.
a. Of medium strength
b. Of weak strength
c. Perfect
d. 0
ANS: C
PTS: 1
DIF: Medium
REF: The Logic of Prediction
OBJ: How and why linear regression works when predicting one variable from another
COG: Knowledge
11. When adding additional predictors to a regression analysis, you should try to find predictors

that are related to _______ but not _______.
a. The independent variable; the dependent variables
b. The dependent variable; the independent variables
c. The predictors; the outcome
d. All main effects; any interaction effect
ANS: B
PTS: 1
DIF: Medium
REF: The Big Rule When It Comes to Using Multiple Predictor Variables
OBJ: What multiple regression is and why it is useful
COG: Comprehension
12. What is another name for a regression line?
a. Line of best fit
b. Scatter plot line
c. Line graph

d. Line of the estimate
ANS: A
PTS: 1
DIF: Medium
REF: The Logic of Prediction
OBJ: How and why linear regression works when predicting one variable from another
COG: Knowledge
13. What is the distance between each data point and the regression line called?
a. Error of the estimate
b. Standard error of the estimate


c. Standard deviation
d. Standardized error
ANS: A
PTS: 1
REF: How Good Is Our Prediction?
COG: Knowledge

DIF: Medium
OBJ: How to judge the accuracy of predictions

14. Which of the following is the correct formula for linear regression?
a.
= aY + b
b.

= aX + b

c.

= bX + a

d.

= bY + a

ANS:
REF:
OBJ:
COG:

C
PTS: 1
DIF: Hard
Drawing the World’s Best Line (for Your Data)
How and why linear regression works when predicting one variable from another
Knowledge

15. Which of the following symbols is associated with the predicted score in the regression

equation?
a. X
b.
c. a
d. b
ANS:
REF:
OBJ:
COG:

B
PTS: 1
DIF: Medium
Drawing the World’s Best Line (for Your Data)
How and why linear regression works when predicting one variable from another
Knowledge

16. Which of the following symbols is associated with the independent variable in the regression

equation?
a. X
b.
c. a
d. b
ANS:
REF:
OBJ:
COG:

A
PTS: 1
DIF: Medium
Drawing the World’s Best Line (for Your Data)
How and why linear regression works when predicting one variable from another
Knowledge

17. Which of the following symbols is associated with the slope in the regression equation?
a. X

b.
c. a
d. b
ANS:
REF:
OBJ:
COG:

D
PTS: 1
DIF: Medium
Drawing the World’s Best Line (for Your Data)
How and why linear regression works when predicting one variable from another
Knowledge

18. Which of the following symbols is associated with the y-intercept in the regression equation?
a. X
b.
c. a
d. b
ANS:
REF:
OBJ:
COG:

C
PTS: 1
DIF: Medium
Drawing the World’s Best Line (for Your Data)

How and why linear regression works when predicting one variable from another
Knowledge

19. In regression, the criterion variable is also known as the _______.
a. Dependent variable
b. Independent variable
c. Predictor variable
d. Correlated variable
ANS:
REF:
OBJ:
COG:

A
PTS: 1
DIF: Medium
Drawing the World’s Best Line (for Your Data)
How and why linear regression works when predicting one variable from another
Knowledge

20. How would you represent the predicted score of Y based on a known value of X?
a. y
b. y-intercept
c.
d. Y = Xa
ANS:
REF:
OBJ:
COG:

C
PTS: 1
DIF: Medium
Drawing the World’s Best Line (for Your Data)
How and why linear regression works when predicting one variable from another
Comprehension

21. Which of the following determines the direction of the regression line?
a. Intercept
b. Predicted score


c. Criterion score
d. Slope
ANS:
REF:
OBJ:
COG:

D
PTS: 1
DIF: Medium
Drawing the World’s Best Line (for Your Data)
How and why linear regression works when predicting one variable from another
Knowledge

22. Which of the following is the point at which the regression line crosses the y-axis?
a. Intercept
b. Predicted point
c. Criterion point

d. Slope
ANS:
REF:
OBJ:
COG:

A
PTS: 1
DIF: Medium
Drawing the World’s Best Line (for Your Data)
How and why linear regression works when predicting one variable from another
Knowledge

23. Using the regression formula with a slope = .704 and an intercept = .719, what would the

predicted college GPA be for a student whose current high school GPA = 3.2?
a. 2.69
b. 2.97
c. 3.00
d. 3.20
ANS:
REF:
OBJ:
COG:

B
PTS: 1
DIF: Medium
Drawing the World’s Best Line (for Your Data)
How and why linear regression works when predicting one variable from another

Application

24. Using the regression formula with a slope = 2,000 and an intercept = 15,000, what would the

predicted income be for someone who has 16 years of education?
a. $40,000
b. $42,000
c. $45,000
d. $47,000
ANS:
REF:
OBJ:
COG:

D
PTS: 1
DIF: Medium
Drawing the World’s Best Line (for Your Data)
How and why linear regression works when predicting one variable from another
Application

25. Using the regression formula with a slope = 1,000 and an intercept = 25,000, what would the

predicted income be for someone who has 20 years of education?
a. $40,000
b. $42,000


c. $45,000
d. $47,000

ANS:
REF:
OBJ:
COG:

C
PTS: 1
DIF: Medium
Drawing the World’s Best Line (for Your Data)
How and why linear regression works when predicting one variable from another
Application

26. How is the

symbol interpreted?

a. Y intercept
b. Y predictor
c. Y prime
d. Y score
ANS:
REF:
OBJ:
COG:

C
PTS: 1
DIF: Medium
Drawing the World’s Best Line (for Your Data)
How and why linear regression works when predicting one variable from another

Comprehension

27. A positive trend line is associated with what type of slope?
a. Negative slope
b. Direct slope
c. Positive slope
d. Nondirectional slope
ANS:
REF:
OBJ:
COG:

C
PTS: 1
DIF: Medium
Drawing the World’s Best Line (for Your Data)
How and why linear regression works when predicting one variable from another
Comprehension

28. Which of the following is like a standard deviation for all error scores in regression?
a. Error of the estimate
b. Error standard deviation
c. Standard error of the estimate
d. Precision of error score
ANS: C
PTS: 1
REF: How Good Is Our Prediction?
COG: Knowledge

DIF: Medium

OBJ: How to judge the accuracy of predictions

29. What must be done to categorical variables in order to use them in a regression analysis?
a. Nothing
b. Dummy coding
c. Problem coding
d. Categorical coding
ANS: B

PTS: 1

DIF: Medium


REF: How Good Is Our Prediction?
COG: Knowledge

OBJ: How to judge the accuracy of predictions

30. What must be used to examine an outcome that is predicted from two independent variables?
a. Multivariate regression
b. Multiple regression
c. Simple regression
d. Complicated regression
ANS: B
PTS: 1
DIF: Medium
REF: The More Predictors, the Better? Maybe
OBJ: What multiple regression is and why it is useful

COG: Comprehension

31. Which of the following is also known as a regression weight?
a. X
b.
c. a
d. b
ANS:
REF:
OBJ:
COG:

D
PTS: 1
DIF: Medium
Drawing the World’s Best Line (for Your Data)
How and why linear regression works when predicting one variable from another
Knowledge

32. When using two predictor variables, these variables should be _______.
a. Correlated
b. Related
c. Independent
d. Dependent
ANS: C
PTS: 1
DIF: Medium
REF: The Big Rule When It Comes to Using Multiple Predictor Variables
OBJ: How to judge the accuracy of predictions
COG: Comprehension

33. In the multiple-regression formula, what does X2 represent?
a. Value of the second dependent variable
b. Value of the second independent variable
c. Value of the criterion variable
d. Value of the predicted score
ANS:
REF:
OBJ:
COG:

B
PTS: 1
DIF: Medium
Drawing the World’s Best Line (for Your Data)
How and why linear regression works when predicting one variable from another
Knowledge

34. If the correlation between X and Y is equal to -1.0, what do we know about the prediction of Y

by X?


a. It’s weak.
b. It’s positive.
c. It’s perfect.
d. It’s direct.
ANS: C
PTS: 1
REF: How Good Is Our Prediction?
COG: Comprehension

DIF: Medium
OBJ: How to judge the accuracy of predictions

35. A regression equation can be visually represented on a(n) _______.
a. Histogram
b. Scatter plot
c. Ogive
d. Pie chart
ANS: B
PTS: 1
DIF: Medium
REF: The Logic of Prediction
OBJ: How and why linear regression works when predicting one variable from another
COG: Knowledge
36. If you are trying to predict Y scores from X scores, Y is referred to as the _______.
a. Nominal variable
b. Independent variable
c. Predictor variable
d. Criterion variable
ANS:
REF:
OBJ:
COG:

D
PTS: 1
DIF: Medium
Drawing the World’s Best Line (for Your Data)
How and why linear regression works when predicting one variable from another

Comprehension

37. If you are trying to predict Y scores from X scores, X is referred to as the _______.
a. Nominal variable
b. Dependent variable
c. Predictor variable
d. Criterion variable
ANS:
REF:
OBJ:
COG:

C
PTS: 1
DIF: Medium
Drawing the World’s Best Line (for Your Data)
How and why linear regression works when predicting one variable from another
Comprehension

38. The general formula for a regression line is _______.
a. a2 + b2 = c2
b. aX + b = Y
c. bX + a =


d. dX + a =
ANS:
REF:
OBJ:
COG:

C
PTS: 1
DIF: Hard
Drawing the World’s Best Line (for Your Data)
How and why linear regression works when predicting one variable from another
Knowledge

39. Based on the formula for a regression line, what does b represent?
a. Known value of X
b. Slope of a line
c. y-intercept
d. Predictor score
ANS:
REF:
OBJ:
COG:

B
PTS: 1
DIF: Medium
Drawing the World’s Best Line (for Your Data)
How and why linear regression works when predicting one variable from another
Knowledge

40. Based on the formula for a regression line, what does a represent?
a. Known value of X
b. Slope of a line
c. y-intercept
d. Predictor score

ANS:
REF:
OBJ:
COG:

C
PTS: 1
DIF: Medium
Drawing the World’s Best Line (for Your Data)
How and why linear regression works when predicting one variable from another
Knowledge

41. Not all lines that are the best fit for a bunch of data points are straight. Rather, they could be

_______.
a. Linear
b. Invalid
c. Curvilinear
d. Parallel-linear
ANS:
REF:
OBJ:
COG:

C
PTS: 1
DIF: Hard
Drawing the World’s Best Line (for Your Data)
How and why linear regression works when predicting one variable from another
Knowledge

42. The INTERCEPT function in Excel computes the location where the regression line crosses

the _______.
a. c-axis
b. b-axis
c. x-axis


d. y-axis
ANS: D
PTS: 1
DIF: Medium
REF: And Now . . . Using Excel’s INTERCEPT Function
OBJ: How to use the INTERCEPT and SLOPE functions

COG: Knowledge

43. The Excel output for a completed regression includes the following EXCEPT _______.
a. Intercept value
b. p value
c. r value
d. L value
ANS:
REF:
OBJ:
COG:

D
PTS: 1

DIF: Medium
Using the Amazing Data Analysis Tools to Compute the Regression Equation
How to use the always cool Data Analysis Regression tool
Comprehension

44. When setting up the regression line in the Excel dialog box, you should define the _______ of

the data you want Excel to use.
a. Validity
b. Error of estimate
c. Standard error of estimate
d. Range
ANS:
REF:
OBJ:
COG:

D
PTS: 1
DIF: Medium
Using the Amazing Data Analysis Tools to Compute the Regression Equation
How to use the always cool Data Analysis Regression tool
Comprehension

45. When determining the number of predictor variables to use to predict a criterion variable, you

need to keep all of the following guidelines in mind EXCEPT this:
a. The unique contribution of each predictor
b. The practical costs of adding new predictors
c. The relationship between predictors and the criterion variable

d. The length of the dialog box
ANS: D
PTS: 1
DIF: Medium
REF: The Big Rule When It Comes to Using Multiple Predictor Variables
OBJ: What multiple regression is and why it is useful
COG: Comprehension
46. In multiple regression, added variables must be related to the outcome variable but
a. Correlated with and unrelated to each other
b. Independent of and correlated with each other
c. Independent of and uncorrelated with each other
d. Dependent of and uncorrelated with each other
ANS: C

PTS: 1

DIF: Medium


REF: The Big Rule When It Comes to Using Multiple Predictor Variables
OBJ: What multiple regression is and why it is useful
COG: Comprehension
TRUE/FALSE
1. Linear regression uses correlations between variables as the basis for the prediction of the

value of one variable based on the value of another.
ANS: T
PTS: 1
DIF: Medium
REF: The Logic of Prediction

OBJ: How and why linear regression works when predicting one variable from another
COG: Knowledge
2. The higher the absolute value of the correlation coefficient, the less accurate the prediction is

of one variable based on the other variable.
ANS: F
PTS: 1
REF: What Is Prediction All About?
COG: Comprehension

DIF: Medium
OBJ: How to judge the accuracy of predictions

3. A perfect correlation would translate into perfect prediction in the case of linear regression.
ANS: T
PTS: 1
DIF: Medium
REF: The Logic of Prediction
OBJ: How and why linear regression works when predicting one variable from another
COG: Comprehension
4. In linear regression, a regression equation is determined, which can be used to plot a

regression line.
ANS: T
PTS: 1
DIF: Medium
REF: The Logic of Prediction
OBJ: How and why linear regression works when predicting one variable from another
COG: Comprehension
5. The regression line reflects the best estimate of predicted scores for the independent variable

based on levels of the dependent variable.
ANS: F
PTS: 1
DIF: Medium
REF: The Logic of Prediction
OBJ: How and why linear regression works when predicting one variable from another
COG: Knowledge
6. Error in prediction (error of estimate) is calculated as the distance between each individual

data point and the regression line.
ANS: T
PTS: 1
REF: How Good Is Our Prediction?
COG: Knowledge

DIF: Medium
OBJ: How to judge the accuracy of predictions

7. Standard error of estimate is computed as the variance of all values for error in prediction.
ANS: F

PTS: 1

DIF: Medium


REF: How Good Is Our Prediction?
COG: Comprehension

OBJ: How to judge the accuracy of predictions

8. The standard error of estimate tells you how much imprecision there is overall in regard to the

predictive power of the linear regression analysis.
ANS: T
PTS: 1
REF: How Good Is Our Prediction?
COG: Comprehension

DIF: Medium
OBJ: How to judge the accuracy of predictions

9. In linear regression, the outcome variable is called the criterion or dependent variable.
ANS:
REF:
OBJ:
COG:

T
PTS: 1
DIF: Medium
Drawing the World’s Best Line (for Your Data)
How and why linear regression works when predicting one variable from another
Comprehension

10. Simple linear regression consists of a type of regression in which more than one independent

variable is included in the analysis.
ANS:

REF:
OBJ:
COG:

F
PTS: 1
DIF: Medium
The More Predictors, the Better? Maybe
How and why linear regression works when predicting one variable from another
Comprehension

11. One of the values of regression is that you can use data from past events (such as the existing

relationship between two variables) and then apply it later with different cases in which you
have knowledge of only one variable.
ANS:
REF:
OBJ:
COG:

T
PTS: 1
DIF: Medium
What Is Prediction All About?
How prediction works and how it can be used in the social and behavioral sciences
Comprehension

12. Prediction through regression is the computation of past outcomes based on knowledge of

present ones.

ANS:
REF:
OBJ:
COG:

F
PTS: 1
DIF: Medium
What Is Prediction All About?
How prediction works and how it can be used in the social and behavioral sciences
Comprehension

13. The error of estimate and the error of prediction are not the same thing.
ANS: F
PTS: 1
REF: How Good Is Our Prediction?
COG: Knowledge
SHORT ANSWER

DIF: Easy
OBJ: How to judge the accuracy of predictions


1. What is linear regression?
ANS:

Linear regression is a statistical procedure used to predict a Y score from an X score based on
the correlation between a distribution of X scores and a distribution of Y scores.
PTS: 1
DIF: Hard

REF: The Logic of Prediction
OBJ: How and why linear regression works when predicting one variable from another
COG: Knowledge
2. If the correlation between variable X and variable Y is perfect, what do you know about the

prediction?
ANS:

The prediction will be perfect as well.
PTS: 1
DIF: Medium
REF: What Is Prediction All About?
OBJ: How prediction works and how it can be used in the social and behavioral sciences
COG: Comprehension
3. What does the regression line represent?
ANS:

The regression line represents four things. First, it is the line of best fit, which minimizes that
distance between the line and each of the points of the predicted variable on a scatter plot.
Second, the line allows us to predict one score given the value of the independent variable.
The regression line also represents the distance between each individual point and the
regression line, called the error in prediction or error in estimate. Finally, the line allows us to
see how far off each of the data points are from a perfect correlation. If the correlation were
perfect, all the data points would be lined up along a 45 angle.
PTS: 1
DIF: Hard
REF: The Logic of Prediction
OBJ: How and why linear regression works when predicting one variable from another
COG: Comprehension
4. Why is the regression line called the line of best fit?

ANS:

Because the regression line minimizes the distance between each individual point and the
regression line.
PTS: 1
DIF: Medium
REF: The Logic of Prediction
OBJ: How and why linear regression works when predicting one variable from another
COG: Knowledge


5. Why do we use

and not Y in the regression equation?

ANS:

We use

because it is the predicted value of Y, not the actual Y value.

PTS: 1
DIF: Medium
REF: Drawing the World’s Best Line (for Your Data)
OBJ: How and why linear regression works when predicting one variable from another
COG: Comprehension
6. What is the standard error of estimate?
ANS:

The standard error of estimate is the measurement for how well (or poorly) one variable

predicts another variable. When these differences from a distribution of data points are
averaged, the standard error of estimate reflects how good the prediction is.
PTS: 1
DIF: Hard
REF: How Good Is Our Prediction?
OBJ: How to judge the accuracy of predictions
COG: Knowledge
7. How does linear regression differ from multiple regression?
ANS:

Linear regression is a statistical technique using a regression equation to determine the line of
best fit from which a Y score can be predicted from an X score. Multiple regression has the
same goal as linear regression (determining the line of best fit) but uses two or more
independent variables rather than one independent variable (which is what is used in linear
regression).
PTS: 1
DIF: Hard
REF: The More Predictors, the Better? Maybe
OBJ: What multiple regression is and why it is useful
COG: Analysis
8. How is the regression line related to the correlation coefficient?
ANS:

The regression line is a direct reflection of the correlation between two variables. The
correlation coefficient is represented as a value while the regression line is a visual
representation.
PTS: 1
DIF: Hard
REF: The Logic of Prediction
OBJ: How and why linear regression works when predicting one variable from another

COG: Analysis
9. What does a unique contribution mean for a variable?
ANS:


A unique contribution means the variable explains differences in the predicted variable that
the other variables used did not.
PTS: 1
DIF: Medium
REF: The Big Rule When It Comes to Using Multiple Predictor Variables
OBJ: What multiple regression is and why it is useful
COG: Comprehension
10. What important guideline should you keep in mind when choosing independent variables for

multiple regression?
ANS:

When using a multiple-regression model, the predictor variables should be independent and
unrelated with one another but related to the outcome variable.
PTS: 1
DIF: Medium
REF: The Big Rule When It Comes to Using Multiple Predictor Variables
OBJ: What multiple regression is and why it is useful
COG: Comprehension
11. If you are not satisfied with the percentage of variability on your criterion variable accounted

for by the variability in the predictor variable, and if you have an idea of other variables that
could account for the variability in the criterion variable, you could run a _______.
ANS:

multiple regression
PTS: 1
DIF: Medium
REF: The More Predictors, the Better? Maybe
OBJ: What multiple regression is and why it is useful
COG: Comprehension