Question 1

The numerical value for a correlation _____.

Accepted Answer

A) can never be greater than 1.00 
B) can never be less than -1.00 
C) can never be greater than 1.00 and can never be less than -1.00 
D) can be greater than 1.00 and can be less than -1.00 
A) can never be greater than 1.00 
B) can never be less than -1.00 
C) can never be greater than 1.00 and can never be less than -1.00 
D) can be greater than 1.00 and can be less than -1.00

Question 2

The Pearson and the Spearman correlations are both computed for the same set of data.If the Pearson correlation is r = +1.00, then what can you conclude about the Spearman correlation?

Accepted Answer

A) It will be positive. 
B) It will have a value of 1.00 
C) It will be positive and have a value of 1.00 
D) There is no predictable relationship between the Pearson and the Spearman correlations. 
A) It will be positive. 
B) It will have a value of 1.00 
C) It will be positive and have a value of 1.00 
D) There is no predictable relationship between the Pearson and the Spearman correlations.

Question 3

If you measured hearing acuity and age for a group of people who are 50 to 90 years old, you should obtain a negative correlation between the two variables.

Accepted Answer

A) True 
 B)False

Question 4

For a positive correlation, decreases in X tend to be accompanied by decreases in Y.

Accepted Answer

A) True 
 B)False

Question 5

A set of n = 15 pairs of scores (X and Y values) produces a correlation of r = 0.40.If each of the X values is multiplied by 2 and the correlation is computed for the new scores, what value will be obtained for the new correlation?

Accepted Answer

A) r = 0.20 
B) r = 0.40 
C) r = 0.80 
D) cannot be determined without knowing all the X and Y scores 
A) r = 0.20 
B) r = 0.40 
C) r = 0.80 
D) cannot be determined without knowing all the X and Y scores

Question 6

A correlation of r = -0.95 means that there is essentially no consistent relationship between X and Y.

Accepted Answer

A) True 
 B)False

Question 7

The Spearman correlation can be +1.00 or -1.00 even when there is no linear relationship between the two variables.

Accepted Answer

A) True 
 B)False

Question 8

For a two-tailed hypothesis test evaluating the significance of a Pearson correlation, the null hypothesis states that the correlation for the population is zero.

Accepted Answer

A) True 
 B)False

Question 9

The sign of the correlation (+/-) is generally meaningless for the point-biserial correlation and the phi-coefficient.

Accepted Answer

A) True 
 B)False

Question 10

A Spearman correlation of rS = 0.45 is computed for a sample of n = 22 people.This is sufficient to conclude that there is a real (non-zero) correlation in the population.

Accepted Answer

A) True 
 B)False

Question 11

The effect size for the data from an independent-measures t test can be measured by r2 which is the percentage of variance accounted for.Which of the following also produces the value for r2?

Accepted Answer

A) squaring the Spearman correlation for the same data 
B) squaring the point-biserial correlation for the same data 
C) squaring the Pearson correlation for the same data 
D) None of the other options will produce r2. 
A) squaring the Spearman correlation for the same data 
B) squaring the point-biserial correlation for the same data 
C) squaring the Pearson correlation for the same data 
D) None of the other options will produce r2.

Question 12

A Pearson correlation of r = -0.90 indicates that the data points are clustered close to a line that slopes down to the right.

Accepted Answer

A) True 
 B)False

Question 13

If the Pearson correlation is calculated for a sample of n = 20 individuals, what value for df should be used to determine whether or not the correlation is significant?

Accepted Answer

A) 18 
B) 19 
C) 20 
D) 21 
A) 18 
B) 19 
C) 20 
D) 21

Question 14

A set of n = 5 pairs of X and Y values has SSX = 16, SSY = 4 and SP = 2.For these data, the Pearson correlation is _____.

Accepted Answer

A)  $ \mathrm{r}=2 / 64 $ 
B)  $ r=2 / 8 $ 
C)  $ \mathrm{r}=\sqrt{2 / 8} $ 
D)  $ r=64 / 64 $ 
A)  $ \mathrm{r}=2 / 64 $ 
B)  $ r=2 / 8 $ 
C)  $ \mathrm{r}=\sqrt{2 / 8} $ 
D)  $ r=64 / 64 $

Question 15

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

Accepted Answer

A) 3 
B) 4 
C) 5 
D) 6 
A) 3 
B) 4 
C) 5 
D) 6

Question 16

A negative correlation means that decreases in the X variable tend to be accompanied by decreases in the Y variable.

Accepted Answer

A) True 
 B)False

Question 17

Suppose that there is a correlation of r = -0.41 between the amount of time that each student reports studying for an exam and the student's grade on the exam.This correlation would mean that there is a tendency for people who study more to get better grades.

Accepted Answer

A) True 
 B)False

Question 18

For a set of n = 10 pairs of scores with $\Sigma $X = 10, $\Sigma $Y = 40, and $\Sigma $XY = 50, the sum of products of deviation is SP = 10.

Accepted Answer

A) True 
 B)False

Question 19

The scatter plot for a set of X and Y values shows the data points clustered in a nearly perfect circle.For these data, what is the most likely value for the Pearson correlation?

Accepted Answer

A) a positive correlation near 0 
B) a negative correlation near 0 
C) either positive or negative near 0 
D) a value near +1.00 or -1.00 
A) a positive correlation near 0 
B) a negative correlation near 0 
C) either positive or negative near 0 
D) a value near +1.00 or -1.00

Question 20

A Pearson correlation is computed for a sample of n = 18 pairs of X and Y values.What correlations are statistically significant with α = .05, two tails.

Accepted Answer

A) correlations between 0.468 and -0.468 
B) correlations greater than or equal to 0.468 and correlation less than or equal to -0.468 
C) correlations between 0.456 and -0.456 
D) correlations greater than or equal to 0.456 and correlation less than or equal to -0.456 
A) correlations between 0.468 and -0.468 
B) correlations greater than or equal to 0.468 and correlation less than or equal to -0.468 
C) correlations between 0.456 and -0.456 
D) correlations greater than or equal to 0.456 and correlation less than or equal to -0.456

The numerical value for a correlation _____.

The Pearson and the Spearman correlations are both computed for the same set of data.If the Pearson correlation is r = +1.00, then what can you conclude about the Spearman correlation?

If you measured hearing acuity and age for a group of people who are 50 to 90 years old, you should obtain a negative correlation between the two variables.

For a positive correlation, decreases in X tend to be accompanied by decreases in Y.

A set of n = 15 pairs of scores (X and Y values) produces a correlation of r = 0.40.If each of the X values is multiplied by 2 and the correlation is computed for the new scores, what value will be obtained for the new correlation?

A correlation of r = -0.95 means that there is essentially no consistent relationship between X and Y.

The Spearman correlation can be +1.00 or -1.00 even when there is no linear relationship between the two variables.

For a two-tailed hypothesis test evaluating the significance of a Pearson correlation, the null hypothesis states that the correlation for the population is zero.

The sign of the correlation (+/-) is generally meaningless for the point-biserial correlation and the phi-coefficient.

A Spearman correlation of r_S = 0.45 is computed for a sample of n = 22 people.This is sufficient to conclude that there is a real (non-zero) correlation in the population.

The effect size for the data from an independent-measures t test can be measured by r² which is the percentage of variance accounted for.Which of the following also produces the value for r²?

A Pearson correlation of r = -0.90 indicates that the data points are clustered close to a line that slopes down to the right.

If the Pearson correlation is calculated for a sample of n = 20 individuals, what value for df should be used to determine whether or not the correlation is significant?

A set of n = 5 pairs of X and Y values has SS_X = 16, SS_Y = 4 and SP = 2.For these data, the Pearson correlation is _____.

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

A negative correlation means that decreases in the X variable tend to be accompanied by decreases in the Y variable.

Suppose that there is a correlation of r = -0.41 between the amount of time that each student reports studying for an exam and the student's grade on the exam.This correlation would mean that there is a tendency for people who study more to get better grades.

For a set of n = 10 pairs of scores with $\Sigma$ X = 10, $\Sigma$ Y = 40, and $\Sigma$ XY = 50, the sum of products of deviation is SP = 10.

The scatter plot for a set of X and Y values shows the data points clustered in a nearly perfect circle.For these data, what is the most likely value for the Pearson correlation?

A Pearson correlation is computed for a sample of n = 18 pairs of X and Y values.What correlations are statistically significant with α = .05, two tails.

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

The numerical value for a correlation _____.

The Pearson and the Spearman correlations are both computed for the same set of data.If the Pearson correlation is r = +1.00, then what can you conclude about the Spearman correlation?

If you measured hearing acuity and age for a group of people who are 50 to 90 years old, you should obtain a negative correlation between the two variables.

For a positive correlation, decreases in X tend to be accompanied by decreases in Y.

A set of n = 15 pairs of scores (X and Y values) produces a correlation of r = 0.40.If each of the X values is multiplied by 2 and the correlation is computed for the new scores, what value will be obtained for the new correlation?

A correlation of r = -0.95 means that there is essentially no consistent relationship between X and Y.

The Spearman correlation can be +1.00 or -1.00 even when there is no linear relationship between the two variables.

For a two-tailed hypothesis test evaluating the significance of a Pearson correlation, the null hypothesis states that the correlation for the population is zero.

The sign of the correlation (+/-) is generally meaningless for the point-biserial correlation and the phi-coefficient.

A Spearman correlation of rS = 0.45 is computed for a sample of n = 22 people.This is sufficient to conclude that there is a real (non-zero) correlation in the population.

The effect size for the data from an independent-measures t test can be measured by r2 which is the percentage of variance accounted for.Which of the following also produces the value for r2?

A Pearson correlation of r = -0.90 indicates that the data points are clustered close to a line that slopes down to the right.

If the Pearson correlation is calculated for a sample of n = 20 individuals, what value for df should be used to determine whether or not the correlation is significant?

A set of n = 5 pairs of X and Y values has SSX = 16, SSY = 4 and SP = 2.For these data, the Pearson correlation is _____.

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

A negative correlation means that decreases in the X variable tend to be accompanied by decreases in the Y variable.

Suppose that there is a correlation of r = -0.41 between the amount of time that each student reports studying for an exam and the student's grade on the exam.This correlation would mean that there is a tendency for people who study more to get better grades.

For a set of n = 10 pairs of scores with Σ\Sigma Σ X = 10, Σ\Sigma Σ Y = 40, and Σ\Sigma Σ XY = 50, the sum of products of deviation is SP = 10.

The scatter plot for a set of X and Y values shows the data points clustered in a nearly perfect circle.For these data, what is the most likely value for the Pearson correlation?

A Pearson correlation is computed for a sample of n = 18 pairs of X and Y values.What correlations are statistically significant with α = .05, two tails.

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 Spearman correlation of r_S = 0.45 is computed for a sample of n = 22 people.This is sufficient to conclude that there is a real (non-zero) correlation in the population.

The effect size for the data from an independent-measures t test can be measured by r² which is the percentage of variance accounted for.Which of the following also produces the value for r²?

A set of n = 5 pairs of X and Y values has SS_X = 16, SS_Y = 4 and SP = 2.For these data, the Pearson correlation is _____.

For a set of n = 10 pairs of scores with $\Sigma$ X = 10, $\Sigma$ Y = 40, and $\Sigma$ XY = 50, the sum of products of deviation is SP = 10.