Question 1

Under what circumstances is the phi-coefficient used?

Accepted Answer

A) When one variable consists of ranks and the other is regular, numerical scores. 
B) When both variables consists of ranks. 
C) When both X and Y are dichotomous variables 
D) When one variable is dichotomous and the other is regular, numerical scores. 
A) When one variable consists of ranks and the other is regular, numerical scores. 
B) When both variables consists of ranks. 
C) When both X and Y are dichotomous variables 
D) When one variable is dichotomous and the other is regular, numerical scores.

Question 2

The value obtained for the sum of products, SP, determines the sign (+/-) for the correlation.

Accepted Answer

A) True 
 B)False

Question 3

The results from a research study indicate that adolescents who watch more violent content on television also tend to engage in more violent behavior than their peers.The correlation between amount of TV violent content and amount of violent behavior is an example of

Accepted Answer

A) a positive correlation. 
B) a negative correlation. 
C) a correlation near zero. 
D) a correlation near one. 
A) a positive correlation. 
B) a negative correlation. 
C) a correlation near zero. 
D) a correlation near one.

Question 4

If the Spearman correlation for a set of scores is equal to +1.00, then the Pearson correlation for the same scores would also be equal to +1.00.
definitely

Accepted Answer

A) True 
 B)False

Question 5

Which of the following best describes the Pearson correlation for these data? $\begin{array}{ll}
\mathrm{X} & \mathrm{Y} \
\hline 2 & 5 \
5 & 1 \
3 & 4 \
4 & 2
\end{array}$

Accepted Answer

A)  ispositive 
B)  is negative 
C)  is zero 
D)  cannot be determined 
A)  ispositive 
B)  is negative 
C)  is zero 
D)  cannot be determined

Question 6

What is the value of SP for the following set of data? $\begin{array}{cc}
\mathrm{X} & \mathrm{Y} \
\hline 1 & 4 \
2 & 4 \
9 & 1
\end{array}$

Accepted Answer

A)  5 
B)  $ -5 $ 
C)  15 
D)  $ -15 $ 
A)  5 
B)  $ -5 $ 
C)  15 
D)  $ -15 $

Question 7

Using a two-tailed test with α = .05, a sample correlation of r = 0.355 for a sample of n = 30 individuals is large enough to conclude that there is a real correlation in the general population.

Accepted Answer

A) True 
 B)False

Question 8

Under what circumstances is the point-biserial correlation used?

Accepted Answer

A) in the same circumstances when a repeated-measures t test would be used 
B) in the same circumstances when an independent-measures t test would be used 
C) when both X and Y are dichotomous variables 
D) when both X and Y are measured on an ordinal scale (ranks) 
A) in the same circumstances when a repeated-measures t test would be used 
B) in the same circumstances when an independent-measures t test would be used 
C) when both X and Y are dichotomous variables 
D) when both X and Y are measured on an ordinal scale (ranks)

Question 9

If the following seven scores are ranked from smallest (#1) to largest, then what rank should be assigned to a score of X = 1? Scores: 1, 1, 1, 1, 3, 6, 6, 6, 9

Accepted Answer

A) 1 
B) 2 
C) 2.5 
D) 4 
A) 1 
B) 2 
C) 2.5 
D) 4

Question 10

A scatter plot shows data points that are widely scattered around a line that slopes down to the right.Which of the following values would be closest to the correlation for these data?

Accepted Answer

A) 0.80 
B) 0.40 
C) -0.40 
D) -0.80 
A) 0.80 
B) 0.40 
C) -0.40 
D) -0.80

Question 11

If people are classified by age (over 30/under 30) and by political affiliation (Democrat/Republican), then the point-biserial correlation would be the proper technique to measure the relationship between the two variables.

Accepted Answer

A) True 
 B)False

Question 12

A researcher obtains a correlation of r = 0.390 for a sample of n = 25 individuals.This correlation is significant using a two-tailed test with $\alpha$ = .05.

Accepted Answer

A) True 
 B)False

Question 13

Which of the following sets of correlations is correctly ordered from the highest to the lowest degree of relationship?

Accepted Answer

A) -0.91, +0.83, +0.10, -0.03 
B) -0.91, +0.83,-0.03, -0.10 
C) +0.83, +0.10, -0.91, -0.03 
D) +0.83, +0.10, -0.03, -0.91 
A) -0.91, +0.83, +0.10, -0.03 
B) -0.91, +0.83,-0.03, -0.10 
C) +0.83, +0.10, -0.91, -0.03 
D) +0.83, +0.10, -0.03, -0.91

Question 14

The phi-coefficient is the correct correlation to use when both X and Y are dichotomous variables.

Accepted Answer

A) True 
 B)False

Question 15

Which of the following Pearson correlations shows the greatest strength or consistency of relationship?

Accepted Answer

A) -0.90 
B) +0.74 
C) +0.85 
D) -0.33 
A) -0.90 
B) +0.74 
C) +0.85 
D) -0.33

Question 16

What is the value of SP for the following set of data? $\begin{array}{ll}
\mathrm{X} & \mathrm{Y} \
\hline 4 & 3 \
1 & 2 \
1 & 5 \
2 & 6
\end{array}$

Accepted Answer

A)  $ -1 $ 
B)  $ -5 $ 
C)  5 
D)  None of the other 3 choices is correct. 
A)  $ -1 $ 
B)  $ -5 $ 
C)  5 
D)  None of the other 3 choices is correct.

Question 17

A set of n = 10 pairs of scores has ΣX = 20, ΣY = 30, and ΣXY = 74.What is the value of SP for these data?

Accepted Answer

A) 74 
B) 24 
C) 14 
D) -14 
A) 74 
B) 24 
C) 14 
D) -14

Question 18

A college professor reports that students who finish exams early tend to get better grades than students who hold on to exams until the last possible moment.The correlation between exam score and amount of time spent on the exam is an example of

Accepted Answer

A) a positive correlation. 
B) a negative correlation. 
C) a correlation near zero. 
D) a correlation near one. 
A) a positive correlation. 
B) a negative correlation. 
C) a correlation near zero. 
D) a correlation near one.

Question 19

As the sample size gets larger, what happens to the size of the correlation that is needed for significance?

Accepted Answer

A) It also gets larger. 
B) It gets smaller. 
C) It stays constant. 
D) There is no consistent relationship between sample size and the critical value for a significant correlation. 
A) It also gets larger. 
B) It gets smaller. 
C) It stays constant. 
D) There is no consistent relationship between sample size and the critical value for a significant correlation.

Question 20

If the Pearson correlation for a set of scores is equal to +1.00, then the Spearman correlation for the same scores would also be equal to +1.00.

Accepted Answer

A) True 
 B)False

Under what circumstances is the phi-coefficient used?

The value obtained for the sum of products, SP, determines the sign (+/-) for the correlation.

The results from a research study indicate that adolescents who watch more violent content on television also tend to engage in more violent behavior than their peers.The correlation between amount of TV violent content and amount of violent behavior is an example of

If the Spearman correlation for a set of scores is equal to +1.00, then the Pearson correlation for the same scores would also be equal to +1.00. definitely

Which of the following best describes the Pearson correlation for these data? 2 5 5 1 3 4 4 2

What is the value of SP for the following set of data? 1 4 2 4 9 1

Using a two-tailed test with α = .05, a sample correlation of r = 0.355 for a sample of n = 30 individuals is large enough to conclude that there is a real correlation in the general population.

Under what circumstances is the point-biserial correlation used?

If the following seven scores are ranked from smallest (#1) to largest, then what rank should be assigned to a score of X = 1? Scores: 1, 1, 1, 1, 3, 6, 6, 6, 9

A scatter plot shows data points that are widely scattered around a line that slopes down to the right.Which of the following values would be closest to the correlation for these data?

If people are classified by age (over 30/under 30) and by political affiliation (Democrat/Republican), then the point-biserial correlation would be the proper technique to measure the relationship between the two variables.

A researcher obtains a correlation of r = 0.390 for a sample of n = 25 individuals.This correlation is significant using a two-tailed test with $\alpha$ = .05.

Which of the following sets of correlations is correctly ordered from the highest to the lowest degree of relationship?

The phi-coefficient is the correct correlation to use when both X and Y are dichotomous variables.

Which of the following Pearson correlations shows the greatest strength or consistency of relationship?

What is the value of SP for the following set of data? 4 3 1 2 1 5 2 6

A set of n = 10 pairs of scores has ΣX = 20, ΣY = 30, and ΣXY = 74.What is the value of SP for these data?

A college professor reports that students who finish exams early tend to get better grades than students who hold on to exams until the last possible moment.The correlation between exam score and amount of time spent on the exam is an example of

As the sample size gets larger, what happens to the size of the correlation that is needed for significance?

If the Pearson correlation for a set of scores is equal to +1.00, then the Spearman correlation for the same scores would also be equal to +1.00.

Introduction to Statistics

Frequency Distributions

Central Tendency

Variability

Z-Scores

Probability

The Distribution of Sample Means

Introduction to Hypothesis Testing

Introduction to the T Statistic

The T Test for Two Independent Samples

The T Test for Two Related Samples

Introduction to Analysis of Variance

Repeated-Measures Anova

Two-Factor Analysis of Variance

Introduction to Regression

Chi-Square Tests

The Binomial Test

Choosing the Right Statistics

Filters

Exam 15: Correlation

Under what circumstances is the phi-coefficient used?

The value obtained for the sum of products, SP, determines the sign (+/-) for the correlation.

The results from a research study indicate that adolescents who watch more violent content on television also tend to engage in more violent behavior than their peers.The correlation between amount of TV violent content and amount of violent behavior is an example of

If the Spearman correlation for a set of scores is equal to +1.00, then the Pearson correlation for the same scores would also be equal to +1.00. definitely

Which of the following best describes the Pearson correlation for these data? 2 5 5 1 3 4 4 2

What is the value of SP for the following set of data? 1 4 2 4 9 1

Using a two-tailed test with α = .05, a sample correlation of r = 0.355 for a sample of n = 30 individuals is large enough to conclude that there is a real correlation in the general population.

Under what circumstances is the point-biserial correlation used?

If the following seven scores are ranked from smallest (#1) to largest, then what rank should be assigned to a score of X = 1? Scores: 1, 1, 1, 1, 3, 6, 6, 6, 9

A scatter plot shows data points that are widely scattered around a line that slopes down to the right.Which of the following values would be closest to the correlation for these data?

If people are classified by age (over 30/under 30) and by political affiliation (Democrat/Republican), then the point-biserial correlation would be the proper technique to measure the relationship between the two variables.

A researcher obtains a correlation of r = 0.390 for a sample of n = 25 individuals.This correlation is significant using a two-tailed test with α\alphaα = .05.

Which of the following sets of correlations is correctly ordered from the highest to the lowest degree of relationship?

The phi-coefficient is the correct correlation to use when both X and Y are dichotomous variables.

Which of the following Pearson correlations shows the greatest strength or consistency of relationship?

What is the value of SP for the following set of data? 4 3 1 2 1 5 2 6

A set of n = 10 pairs of scores has ΣX = 20, ΣY = 30, and ΣXY = 74.What is the value of SP for these data?

A college professor reports that students who finish exams early tend to get better grades than students who hold on to exams until the last possible moment.The correlation between exam score and amount of time spent on the exam is an example of

As the sample size gets larger, what happens to the size of the correlation that is needed for significance?

If the Pearson correlation for a set of scores is equal to +1.00, then the Spearman correlation for the same scores would also be equal to +1.00.

Introduction to Statistics

Frequency Distributions

Central Tendency

Variability

Z-Scores

Probability

The Distribution of Sample Means

Introduction to Hypothesis Testing

Introduction to the T Statistic

The T Test for Two Independent Samples

The T Test for Two Related Samples

Introduction to Analysis of Variance

Repeated-Measures Anova

Two-Factor Analysis of Variance

Introduction to Regression

Chi-Square Tests

The Binomial Test

Choosing the Right Statistics

Filters

A researcher obtains a correlation of r = 0.390 for a sample of n = 25 individuals.This correlation is significant using a two-tailed test with $\alpha$ = .05.