Question 1

One important function of the least-squares regression equation is that________.

Accepted Answer

A)  we can use it to tell if a relationship is linear. 
B)  it summarizes all possible scores on the two variables. 
C)  it makes the scattergram symmetrical. 
D)  it allows us to predict Y scores for any value of X. 
A)  we can use it to tell if a relationship is linear. 
B)  it summarizes all possible scores on the two variables. 
C)  it makes the scattergram symmetrical. 
D)  it allows us to predict Y scores for any value of X. D

Question 2

In a study of the relationship between geographical mobility (number of times a person has changed residences) and number of friends, Pearson's r is reported as .40. Which of the following would be a correct interpretation?

Accepted Answer

A)  Mobility explains 16% of the variation in number of friends. 
B)  There is a strong positive relationship between number of friends and mobility. 
C)  As mobility increases, number of friends decreases. 
D)  Mobility explains 40% of the variation in number of friends. 
A)  Mobility explains 16% of the variation in number of friends. 
B)  There is a strong positive relationship between number of friends and mobility. 
C)  As mobility increases, number of friends decreases. 
D)  Mobility explains 40% of the variation in number of friends. D

Question 3

In addition to random sampling, interval-ratio level of measurement, and a normal sampling distribution, model assumptions for testing Pearson's r for significance include________.

Accepted Answer

A)  bivariate normal distributions. 
B)  a linear relationship. 
C)  uniformity in the variance of the Y scores around the regression line for all values of X. 
D)  All of the answer choices 
A)  bivariate normal distributions. 
B)  a linear relationship. 
C)  uniformity in the variance of the Y scores around the regression line for all values of X. 
D)  All of the answer choices D

Question 4

The appropriate measure of association for situations in which both variables are interval-ratio in level of measurement is________.

Accepted Answer

A)  Pearson's r. 
B)  gamma. 
C)  chi square. 
D)  the slope (b). 
A)  Pearson's r. 
B)  gamma. 
C)  chi square. 
D)  the slope (b).

Question 5

One important limitation of the study of poverty and crime reported in the text is that________.

Accepted Answer

A)  the variables were nominal. 
B)  the sample was non-random. 
C)  prediction is not the same thing as association. 
D)  correlation is not the same thing as causation. 
A)  the variables were nominal. 
B)  the sample was non-random. 
C)  prediction is not the same thing as association. 
D)  correlation is not the same thing as causation.

Question 6

The Y intercept is the point where________.

Accepted Answer

A)  the horizontal axis connects to the vertical axis. 
B)  the regression line crosses the horizontal axis of the scattergram. 
C)  the regression line meets the conditional mean of Y. 
D)  the regression line crosses the vertical axis of the scattergram. 
A)  the horizontal axis connects to the vertical axis. 
B)  the regression line crosses the horizontal axis of the scattergram. 
C)  the regression line meets the conditional mean of Y. 
D)  the regression line crosses the vertical axis of the scattergram.

Question 7

If you wanted to measure the association between the age of people (in years) and the number of arrests for driving while intoxicated, the most appropriate measure of association would be________.

Accepted Answer

A)  gamma. 
B)  lambda. 
C)  phi. 
D)  Pearson's r. 
A)  gamma. 
B)  lambda. 
C)  phi. 
D)  Pearson's r.

Question 8

The direction of a relationship between variables can be detected on a scatterplot by considering the angle of the regression line. The relationship is________.

Accepted Answer

A)  positive when the line slopes upward from left to right. 
B)  positive when the line slopes downward from left to right. 
C)  negative when the line slopes upward from left to right. 
D)  negative when the line slopes downward from right to left. 
A)  positive when the line slopes upward from left to right. 
B)  positive when the line slopes downward from left to right. 
C)  negative when the line slopes upward from left to right. 
D)  negative when the line slopes downward from right to left.

Question 9

After scores of all cases have been located on a scatterplot, a straight line drawn so that it comes as close as possible to touching every score is called the________.

Accepted Answer

A)  regression line. 
B)  line of approximation. 
C)  cluster line. 
D)  scatterplot summary. 
A)  regression line. 
B)  line of approximation. 
C)  cluster line. 
D)  scatterplot summary.

Question 10

For a sample of 15 rural counties in one state, a researcher has collected information about the rate of deaths due to traffic accidents per 1,000,000 population and the percentage of the population which consists of males, age 16 to 25. For these variables, find the least squares regression line and compute r and r squared. Write a sentence or two summarizing and explaining your results.

Accepted Answer

The answer of For a sample of 15 rural counties...

Question 11

The explained variation represents________.

Accepted Answer

A)  the conditional distributions of Y. 
B)  the amount that Y varies. 
C)  the improvement in our ability to predict Y when taking X into account. 
D)  the sum of the squares of all scores of Y. 
A)  the conditional distributions of Y. 
B)  the amount that Y varies. 
C)  the improvement in our ability to predict Y when taking X into account. 
D)  the sum of the squares of all scores of Y.

Question 12

If a = 2 and b = 4, what would the value of Y be when X = 1?

Accepted Answer

A)  4 
B)  6 
C)  2 
D)  1 
A)  4 
B)  6 
C)  2 
D)  1

Question 13

A perfect association between variables can be seen on a scatterplot when________.

Accepted Answer

A)  all dots lie an equal distance from the regression line. 
B)  all dots lie on the regression line. 
C)  the regression line forms a right angle at its intersection with the X axis. 
D)  the regression line is parallel to the X axis. 
A)  all dots lie an equal distance from the regression line. 
B)  all dots lie on the regression line. 
C)  the regression line forms a right angle at its intersection with the X axis. 
D)  the regression line is parallel to the X axis.

Question 14

A study of traffic safety shows a correlation of 0.57 between average speed of traffic and number of fatal accidents for a particular stretch of highway. This means that________.

Accepted Answer

A)  drivers should speed up to get through this area as quickly as possible. 
B)  as speed increases, fatalities decrease. 
C)  fatalities tend to increase as average speed increases. 
D)  every 1 mile per hour increase in average speed increases the number of traffic fatalities by .57. 
A)  drivers should speed up to get through this area as quickly as possible. 
B)  as speed increases, fatalities decrease. 
C)  fatalities tend to increase as average speed increases. 
D)  every 1 mile per hour increase in average speed increases the number of traffic fatalities by .57.

Question 15

Dummy variables make it possible to include ________ in regression analysis.

Accepted Answer

A)  nominal variables 
B)  variables measuring intelligence 
C)  interval-ratio variables 
D)  variables with more than two scores 
A)  nominal variables 
B)  variables measuring intelligence 
C)  interval-ratio variables 
D)  variables with more than two scores

Question 16

The conditional mean of Y for any value of X is found by________.

Accepted Answer

A)  adding the Y scores for the specific value of X and dividing by N. 
B)  adding all the Y scores and dividing by X. 
C)  subtracting the mean of Y from the overall mean of X. 
D)  Any of the answer choices 
A)  adding the Y scores for the specific value of X and dividing by N. 
B)  adding all the Y scores and dividing by X. 
C)  subtracting the mean of Y from the overall mean of X. 
D)  Any of the answer choices

Question 17

If the slope of a regression line is 1.5, then________.

Accepted Answer

A)  for every unit of change in X, there is a change of 1.5 units in Y. 
B)  for every unit of change in Y, there is a change of 1.5 in X. 
C)  the score of each case is 1.5 times higher on Y than on X. 
D)  Y causes X 
A)  for every unit of change in X, there is a change of 1.5 units in Y. 
B)  for every unit of change in Y, there is a change of 1.5 in X. 
C)  the score of each case is 1.5 times higher on Y than on X. 
D)  Y causes X

Question 18

When testing Pearson's r for significance, the null hypothesis is that________.

Accepted Answer

A)  there is no difference between the variables in the population from which the sample was drawn. 
B)  there is no linear association between the variables in the population from which the sample was drawn. 
C)  there is no difference between the sample and the population from which the sample was drawn. 
D)  r = 1.00. 
A)  there is no difference between the variables in the population from which the sample was drawn. 
B)  there is no linear association between the variables in the population from which the sample was drawn. 
C)  there is no difference between the sample and the population from which the sample was drawn. 
D)  r = 1.00.

Question 19

In the study reported in the text, the Pearson's r between the measures of poverty and homicide was 0.57. Which of the following is a reasonable interpretation of this result?

Accepted Answer

A)  Poverty causes homicide. 
B)  Homicide causes poverty. 
C)  As poverty increases, homicide decreases. 
D)  There is a moderate, positive correlation between homicide and poverty. 
A)  Poverty causes homicide. 
B)  Homicide causes poverty. 
C)  As poverty increases, homicide decreases. 
D)  There is a moderate, positive correlation between homicide and poverty.

Question 20

By convention, the independent variable is arrayed along the ______________ in a scatterplot.

Accepted Answer

A)  vertical axis (the ordinate) 
B)  regression line 
C)  horizontal axis (the abscissa) 
D)  calibration line 
A)  vertical axis (the ordinate) 
B)  regression line 
C)  horizontal axis (the abscissa) 
D)  calibration line

One important function of the least-squares regression equation is that________.

In a study of the relationship between geographical mobility (number of times a person has changed residences) and number of friends, Pearson's r is reported as .40. Which of the following would be a correct interpretation?

In addition to random sampling, interval-ratio level of measurement, and a normal sampling distribution, model assumptions for testing Pearson's r for significance include________.

The appropriate measure of association for situations in which both variables are interval-ratio in level of measurement is________.

One important limitation of the study of poverty and crime reported in the text is that________.

The Y intercept is the point where________.

If you wanted to measure the association between the age of people (in years) and the number of arrests for driving while intoxicated, the most appropriate measure of association would be________.

The direction of a relationship between variables can be detected on a scatterplot by considering the angle of the regression line. The relationship is________.

After scores of all cases have been located on a scatterplot, a straight line drawn so that it comes as close as possible to touching every score is called the________.

The explained variation represents________.

If a = 2 and b = 4, what would the value of Y be when X = 1?

A perfect association between variables can be seen on a scatterplot when________.

A study of traffic safety shows a correlation of 0.57 between average speed of traffic and number of fatal accidents for a particular stretch of highway. This means that________.

Dummy variables make it possible to include ________ in regression analysis.

The conditional mean of Y for any value of X is found by________.

If the slope of a regression line is 1.5, then________.

When testing Pearson's r for significance, the null hypothesis is that________.

In the study reported in the text, the Pearson's r between the measures of poverty and homicide was 0.57. Which of the following is a reasonable interpretation of this result?

By convention, the independent variable is arrayed along the ______________ in a scatterplot.

Introduction

Basic Descriptive Statistics Tables Percentages Rates and Ratios and Graphs

Measures of Central Tendency

Measures of Variation

The Normal Curve

Introduction to Inferential Statistics Sampling and the Sampling Distribution

Estimation Procedures

Hypothesis Testing I the One Sample Case

Hypothesis Testing Ii the Two Sample Case

Hypothesis Testing Iii the Analysis of Variance

Hypothesis Testing Iv Chi Square

Bivariate Association for Nominal and Ordinal Level Variables

Elaborating Bivariate Tables

Partial Correlation and Multiple Regression and Correlation

Filters

Exam 13: Association Between Variables Measured at the Interval Ratio Level

One important function of the least-squares regression equation is that________.

In a study of the relationship between geographical mobility (number of times a person has changed residences) and number of friends, Pearson's r is reported as .40. Which of the following would be a correct interpretation?

In addition to random sampling, interval-ratio level of measurement, and a normal sampling distribution, model assumptions for testing Pearson's r for significance include________.

The appropriate measure of association for situations in which both variables are interval-ratio in level of measurement is________.

One important limitation of the study of poverty and crime reported in the text is that________.

The Y intercept is the point where________.

If you wanted to measure the association between the age of people (in years) and the number of arrests for driving while intoxicated, the most appropriate measure of association would be________.

The direction of a relationship between variables can be detected on a scatterplot by considering the angle of the regression line. The relationship is________.

After scores of all cases have been located on a scatterplot, a straight line drawn so that it comes as close as possible to touching every score is called the________.

The explained variation represents________.

If a = 2 and b = 4, what would the value of Y be when X = 1?

A perfect association between variables can be seen on a scatterplot when________.

A study of traffic safety shows a correlation of 0.57 between average speed of traffic and number of fatal accidents for a particular stretch of highway. This means that________.

Dummy variables make it possible to include ________ in regression analysis.

The conditional mean of Y for any value of X is found by________.

If the slope of a regression line is 1.5, then________.

When testing Pearson's r for significance, the null hypothesis is that________.

In the study reported in the text, the Pearson's r between the measures of poverty and homicide was 0.57. Which of the following is a reasonable interpretation of this result?

By convention, the independent variable is arrayed along the ______________ in a scatterplot.

Introduction

Basic Descriptive Statistics Tables Percentages Rates and Ratios and Graphs

Measures of Central Tendency

Measures of Variation

The Normal Curve

Introduction to Inferential Statistics Sampling and the Sampling Distribution

Estimation Procedures

Hypothesis Testing I the One Sample Case

Hypothesis Testing Ii the Two Sample Case

Hypothesis Testing Iii the Analysis of Variance

Hypothesis Testing Iv Chi Square

Bivariate Association for Nominal and Ordinal Level Variables

Elaborating Bivariate Tables

Partial Correlation and Multiple Regression and Correlation

Filters