Question 1

When high scores go with high scores, and low with low, the correlation coefficient will be between _________ and __________.

Accepted Answer

0, 1

Question 2

Provide two reasons why it is important to identify the pattern of correlation in a scatter diagram before proceeding to figure the linear correlation.

Accepted Answer

Identifying whether the pattern of correlation is linear tells you whether it is appropriate to use the standard procedures for calculating a linear correlation.
If the pattern is linear, identifying the direction and approximate strength of correlation before doing the figuring provides a check of the results you derive from the actual calculations.

Question 3

What is the difference between a positive correlation and a negative correlation?

Accepted Answer

A) In a negative correlation high scores go with high scores and low with low; in a positive correlation high scores go with low scores and low with high. 
B) In a negative correlation high scores go with low scores and low with high; in a positive correlation high scores go with high scores and low with low. 
C) Negative correlations are curvilinear; positive correlations are straight lines. 
D) Negative correlations represent a weak relationship; positive correlations represent a strong relationship. 
A) In a negative correlation high scores go with high scores and low with low; in a positive correlation high scores go with low scores and low with high. 
B) In a negative correlation high scores go with low scores and low with high; in a positive correlation high scores go with high scores and low with low. 
C) Negative correlations are curvilinear; positive correlations are straight lines. 
D) Negative correlations represent a weak relationship; positive correlations represent a strong relationship. B

Question 4

A health researcher conducts a survey of the relation of proportion of fat in a person's diet to proportion of time the person uses a seat belt. (The idea is that those who practice one kind of health-related behavior may be more likely to practice another kind.)Here are the scores for three participants.
   M = 36.67 SD = 10.27 M = 53.33 SD = 12.47 r = -.96
a. Give the Z score prediction formula for predicting seat belt usage from fat in their diet.
b. Predict the seat belt usage of a person who has 40% fat in their diet.
c. Explain what you have done to a person who is familiar with correlation but not with regression.

Accepted Answer

a. Predicted Z_Y = (-.96)(Z

Question 5

In a particular industry it is known that the standardized regression coefficient for predicting likely profit from number of advertisements is .7. A company is planning to place 18 advertisements. Which of the following pieces of information will be needed as part of predicting the actual amount of profit?

Accepted Answer

A) Length of time the company has been in business 
B) Mean number of advertisements in general and standard deviation 
C) This company's profit to date 
D) This company's number of advertisements in the previous year 
A) Length of time the company has been in business 
B) Mean number of advertisements in general and standard deviation 
C) This company's profit to date 
D) This company's number of advertisements in the previous year

Question 6

A research article reports that a score is statistically significant. This means that it is unlikely that a correlation this high would have been observed in the group studied if the correlation were in fact zero for __________.

Accepted Answer

people in

Question 7

Which of the following is a way for researchers to rule out alternative directions of causality?

Accepted Answer

A) conduct a longitudinal study 
B) conduct a cross-sectional study 
C) conduct a true experiment 
D) both A and C 
A) conduct a longitudinal study 
B) conduct a cross-sectional study 
C) conduct a true experiment 
D) both A and C

Question 8

A research article reports a significant correlation using the .01 significance level. How would this be presented in the article if the correlation coefficient was .43?

Accepted Answer

A) r = .43, p  .01, r = .43 
A) r = .43, p  .01, r = .43

Question 9

In the social sciences, a strategy to rule out at least one direction of causality is to conduct studies where people are measured:

Accepted Answer

A) on two different variables 
B) on three different variables 
C) at their peak level of performance 
D) in two different settings 
A) on two different variables 
B) on three different variables 
C) at their peak level of performance 
D) in two different settings

Question 10

Which of the alternatives best describes the pattern of scores on the scatter diagram below?

Accepted Answer

A) No correlation 
B) Curvilinear correlation 
C) Positive linear correlation 
D) Negative linear correlation 
A) No correlation 
B) Curvilinear correlation 
C) Positive linear correlation 
D) Negative linear correlation

Question 11

A study finds that the scarier the movie a person is watching, the more popcorn the person will eat. This relation between scariness of movies and popcorn is an example of a(n)__________ correlation.

Accepted Answer

positive,

Question 12

Which of the following represents the strongest linear correlation?

Accepted Answer

A) +)09 
B) +)88 
C) -.92 
D) -.18 
A) +)09 
B) +)88 
C) -.92 
D) -.18

Question 13

In prediction with one predictor variable, the optimal number to use for beta (the standardized regression coefficient)is the:

Accepted Answer

A) proportionate reduction in error 
B) correlation coefficient 
C) sum of squared roots 
D) regression constant 
A) proportionate reduction in error 
B) correlation coefficient 
C) sum of squared roots 
D) regression constant

Question 14

A scatter diagram shows a pattern of dots in which the dots generally go down and to the right. This pattern is an example of a(n)__________ correlation.

Accepted Answer

negative,

Question 15

A researcher surveys a group of working married women and reports the following results for the first four surveyed:
   M = 45 SD = 11.18 M = 82.5 SD = 10.9 r = -.92
a. Give the Z score prediction formula for predicting proportion of housework done from proportion of income contributed.
b. Predict the contribution to housework for a woman who provides 90% of the income.
c. Explain what you have done to a person who is familiar with correlation but not with regression.

Accepted Answer

a. Predicted Z_Y = (-.92)(Z

Question 16

Suppose that you want to be able to predict college grades from information about high school grades. In this case, the college grades would be called the:

Accepted Answer

A) predictor variable 
B) criterion variable 
C) independent variable 
D) causal variable 
A) predictor variable 
B) criterion variable 
C) independent variable 
D) causal variable

Question 17

A scatter diagram shows a pattern of dots in which the dots generally go up and to the right. This pattern is an example of a(n)__________ correlation.

Accepted Answer

positive,

Question 18

When calculating a correlation coefficient, why is it important to divide the sum of cross-products of Z scores by the number of people in the study?

Accepted Answer

The more people in a study, the larger t

Question 19

Suppose that you would like to predict a person's college GPA from the person's SAT score. In this situation, the SAT score is called the:

Accepted Answer

A) predictor variable 
B) dependent variable 
C) criterion variable 
D) positive variable 
A) predictor variable 
B) dependent variable 
C) criterion variable 
D) positive variable

Question 20

Which of the alternatives best describes the pattern of scores graphed below?

Accepted Answer

A) Strong positive linear correlation 
B) Weak negative linear correlation 
C) Strong curvilinear correlation 
D) Weak positive linear correlation 
A) Strong positive linear correlation 
B) Weak negative linear correlation 
C) Strong curvilinear correlation 
D) Weak positive linear correlation

When high scores go with high scores, and low with low, the correlation coefficient will be between _ and __.

Provide two reasons why it is important to identify the pattern of correlation in a scatter diagram before proceeding to figure the linear correlation.

What is the difference between a positive correlation and a negative correlation?

A research article reports that a score is statistically significant. This means that it is unlikely that a correlation this high would have been observed in the group studied if the correlation were in fact zero for __________.

Which of the following is a way for researchers to rule out alternative directions of causality?

A research article reports a significant correlation using the .01 significance level. How would this be presented in the article if the correlation coefficient was .43?

In the social sciences, a strategy to rule out at least one direction of causality is to conduct studies where people are measured:

Which of the alternatives best describes the pattern of scores on the scatter diagram below?

A study finds that the scarier the movie a person is watching, the more popcorn the person will eat. This relation between scariness of movies and popcorn is an example of a(n)__________ correlation.

Which of the following represents the strongest linear correlation?

In prediction with one predictor variable, the optimal number to use for beta (the standardized regression coefficient)is the:

A scatter diagram shows a pattern of dots in which the dots generally go down and to the right. This pattern is an example of a(n)__________ correlation.

Suppose that you want to be able to predict college grades from information about high school grades. In this case, the college grades would be called the:

A scatter diagram shows a pattern of dots in which the dots generally go up and to the right. This pattern is an example of a(n)__________ correlation.

When calculating a correlation coefficient, why is it important to divide the sum of cross-products of Z scores by the number of people in the study?

Suppose that you would like to predict a person's college GPA from the person's SAT score. In this situation, the SAT score is called the:

Which of the alternatives best describes the pattern of scores graphed below?

Displaying the Order in a Group of Numbers Using Tables and Graphs

The Mean, Variance, Standard Deviation, and Z Scores

Some Key Ingredients for Inferential Statistics: the Normal Curve, Sample Versus Population, and Probability

Introduction to Hypothesis Testing

Hypothesis Tests With Means of Samples

Making Sense of Statistical Significance: Effect Size and Statistical Power

Introduction to the T Test: Single Sample and Dependent Means

The T Test for Independent Means

Introduction to the Analysis of Variance

Chi-Square Tests and Strategies When Population Distributions Are Not Normal

Applying Statistical Methods in Your Own Research Project

Filters

Exam 3: Correlation and Prediction

When high scores go with high scores, and low with low, the correlation coefficient will be between _________ and __________.

Provide two reasons why it is important to identify the pattern of correlation in a scatter diagram before proceeding to figure the linear correlation.

What is the difference between a positive correlation and a negative correlation?

A research article reports that a score is statistically significant. This means that it is unlikely that a correlation this high would have been observed in the group studied if the correlation were in fact zero for __________.

Which of the following is a way for researchers to rule out alternative directions of causality?

A research article reports a significant correlation using the .01 significance level. How would this be presented in the article if the correlation coefficient was .43?

In the social sciences, a strategy to rule out at least one direction of causality is to conduct studies where people are measured:

Which of the alternatives best describes the pattern of scores on the scatter diagram below?

A study finds that the scarier the movie a person is watching, the more popcorn the person will eat. This relation between scariness of movies and popcorn is an example of a(n)__________ correlation.

Which of the following represents the strongest linear correlation?

In prediction with one predictor variable, the optimal number to use for beta (the standardized regression coefficient)is the:

A scatter diagram shows a pattern of dots in which the dots generally go down and to the right. This pattern is an example of a(n)__________ correlation.

Suppose that you want to be able to predict college grades from information about high school grades. In this case, the college grades would be called the:

A scatter diagram shows a pattern of dots in which the dots generally go up and to the right. This pattern is an example of a(n)__________ correlation.

When calculating a correlation coefficient, why is it important to divide the sum of cross-products of Z scores by the number of people in the study?

Suppose that you would like to predict a person's college GPA from the person's SAT score. In this situation, the SAT score is called the:

Which of the alternatives best describes the pattern of scores graphed below?

Displaying the Order in a Group of Numbers Using Tables and Graphs

The Mean, Variance, Standard Deviation, and Z Scores

Some Key Ingredients for Inferential Statistics: the Normal Curve, Sample Versus Population, and Probability

Introduction to Hypothesis Testing

Hypothesis Tests With Means of Samples

Making Sense of Statistical Significance: Effect Size and Statistical Power

Introduction to the T Test: Single Sample and Dependent Means

The T Test for Independent Means

Introduction to the Analysis of Variance

Chi-Square Tests and Strategies When Population Distributions Are Not Normal

Applying Statistical Methods in Your Own Research Project

Filters

When high scores go with high scores, and low with low, the correlation coefficient will be between _ and __.