Question 1

Pearson's r is best used with variables at the nominal level of measurement.

Accepted Answer

A) True 
 B)False  False

Question 2

When there are many ties in the rank ordering of two ordinal variables, it is appropriate to calculate Kendall's tau-b.

Accepted Answer

A) True 
 B)False  True

Question 3

When comparing the means of two or more categories of a nominal variable, we can use the eta statistic to depict the strength of the relationship.

Accepted Answer

A) True 
 B)False  True

Question 4

Which of the following statements is correct about keeping or eliminating outliers when calculating the correlation coefficient?

Accepted Answer

A) They should always be eliminated. 
B) They should never be eliminated. 
C) The decision should be based on the option that best supports the hypothesis. 
D) None of these. 
A) They should always be eliminated. 
B) They should never be eliminated. 
C) The decision should be based on the option that best supports the hypothesis. 
D) None of these.

Question 5

A correlation of +.60 between quality of therapist-client relationship and the client's level of self-esteem means that improving the therapist-client relationship is likely to cause the client's self-esteem to improve.

Accepted Answer

A) True 
 B)False

Question 6

Which of the following statements is correct regarding obtaining a correlation coefficient of zero?

Accepted Answer

A) Because there is no correlation, there is no need to examine the scatterplot. 
B) If the scatterplot is curvilinear, that would further support the notion that there is no meaningful relationship between the variables. 
C) If the scatterplot is curvilinear, that might indicate that there is a relationship, but that its nature changes at different levels of the variables. 
D) None of these. 
A) Because there is no correlation, there is no need to examine the scatterplot. 
B) If the scatterplot is curvilinear, that would further support the notion that there is no meaningful relationship between the variables. 
C) If the scatterplot is curvilinear, that might indicate that there is a relationship, but that its nature changes at different levels of the variables. 
D) None of these.

Question 7

A study finds a statistically significant correlation showing that the more treatment appointments missed by spouse abusers, the more abusive incidents.This means that:

Accepted Answer

A) Treatment sessions lower the number of abusive incidents. 
B) Missing treatment sessions increases the risk of abusive incidents. 
C) There is a negative correlation between the number of treatment appointments missed by spouse abusers and the number of abusive incidents. 
D) None of these 
A) Treatment sessions lower the number of abusive incidents. 
B) Missing treatment sessions increases the risk of abusive incidents. 
C) There is a negative correlation between the number of treatment appointments missed by spouse abusers and the number of abusive incidents. 
D) None of these

Question 8

A strong correlation between an independent and dependent variable indicates that the independent variable is a cause of the dependent variable.

Accepted Answer

A) True 
 B)False

Question 9

A curvilinear scatterplot will usually be associated with a strong overall correlation coefficient.

Accepted Answer

A) True 
 B)False

Question 10

A correlation of -.40 is stronger than a correlation of +.30.

Accepted Answer

A) True 
 B)False

Question 11

A correlation of +.95:

Accepted Answer

A) Is stronger than a correlation of -.95. 
B) Signifies an important relationship between two different variables. 
C) Both of the above. 
D) None of these. 
A) Is stronger than a correlation of -.95. 
B) Signifies an important relationship between two different variables. 
C) Both of the above. 
D) None of these.

Question 12

In a study assessing the relationship between the number of close friends who drink alcohol regularly and the number of times a person in treatment for alcohol abuse drank alcohol after completing treatment, the appropriate correlation coefficient to calculate is:

Accepted Answer

A) Pearson's r 
B) Spearman's rho 
C) phi 
D) eta 
A) Pearson's r 
B) Spearman's rho 
C) phi 
D) eta

Question 13

When a correlation coefficient is near perfect:

Accepted Answer

A) One variable is a cause of the other. 
B) The same variable may have been measured in two different ways. 
C) The relationship is positive. 
D) All of these. 
A) One variable is a cause of the other. 
B) The same variable may have been measured in two different ways. 
C) The relationship is positive. 
D) All of these.

Question 14

In a study assessing whether experimental group participants spend fewer days incarcerated than do control group participants, the appropriate correlation coefficient to calculate is:

Accepted Answer

A) Pearson's r 
B) Spearman's rho 
C) phi 
D) eta 
A) Pearson's r 
B) Spearman's rho 
C) phi 
D) eta

Question 15

Just as in other tests of significance, sampling error when testing the statistical significance of correlation coefficients involves the use of theoretical sampling distributions with an assumed mean correlation of zero.

Accepted Answer

A) True 
 B)False

Question 16

When two variables are at the ratio level of measurement, which of the following statements is true about calculating Pearson's r?

Accepted Answer

A) We can disregard whether the degrees of variance in the two variables are similar. 
B) The degree of linearity in the scatterplot won't matter. 
C) The presence of outliers can influence the calculation and interpretation of the correlation coefficient. 
D) All of these. 
A) We can disregard whether the degrees of variance in the two variables are similar. 
B) The degree of linearity in the scatterplot won't matter. 
C) The presence of outliers can influence the calculation and interpretation of the correlation coefficient. 
D) All of these.

Question 17

Phi should be used to calculate the correlation between variables at the ratio level of measurement.

Accepted Answer

A) True 
 B)False

Question 18

Which of the following statements is correct regarding the table below?

Accepted Answer

A) There is a zero correlation between group and outcome. 
B) There is a positive correlation between group and outcome. 
C) There is a negative correlation between group and outcome.. 
D) There is a curvilinear correlation between group and outcome. 
A) There is a zero correlation between group and outcome. 
B) There is a positive correlation between group and outcome. 
C) There is a negative correlation between group and outcome.. 
D) There is a curvilinear correlation between group and outcome.

Question 19

Suppose as the number of abusive incidents increases, the severity of traumatic symptoms increases.This would be:

Accepted Answer

A) A negative correlation. 
B) A positive correlation. 
C) An inverse correlation. 
D) Both a negative and an inverse correlation. 
A) A negative correlation. 
B) A positive correlation. 
C) An inverse correlation. 
D) Both a negative and an inverse correlation.

Question 20

When a scatterplot is clearly curvilinear:

Accepted Answer

A) The calculated correlation coefficient for all the data in the scatterplot may be low. 
B) The calculated correlation coefficient for all the data in the scatterplot will be significant. 
C) As one variable goes up, the other consistently goes down. 
D) None of these. 
A) The calculated correlation coefficient for all the data in the scatterplot may be low. 
B) The calculated correlation coefficient for all the data in the scatterplot will be significant. 
C) As one variable goes up, the other consistently goes down. 
D) None of these.

Pearson's r is best used with variables at the nominal level of measurement.

When there are many ties in the rank ordering of two ordinal variables, it is appropriate to calculate Kendall's tau-b.

When comparing the means of two or more categories of a nominal variable, we can use the eta statistic to depict the strength of the relationship.

Which of the following statements is correct about keeping or eliminating outliers when calculating the correlation coefficient?

A correlation of +.60 between quality of therapist-client relationship and the client's level of self-esteem means that improving the therapist-client relationship is likely to cause the client's self-esteem to improve.

Which of the following statements is correct regarding obtaining a correlation coefficient of zero?

A study finds a statistically significant correlation showing that the more treatment appointments missed by spouse abusers, the more abusive incidents.This means that:

A strong correlation between an independent and dependent variable indicates that the independent variable is a cause of the dependent variable.

A curvilinear scatterplot will usually be associated with a strong overall correlation coefficient.

A correlation of -.40 is stronger than a correlation of +.30.

A correlation of +.95:

In a study assessing the relationship between the number of close friends who drink alcohol regularly and the number of times a person in treatment for alcohol abuse drank alcohol after completing treatment, the appropriate correlation coefficient to calculate is:

When a correlation coefficient is near perfect:

In a study assessing whether experimental group participants spend fewer days incarcerated than do control group participants, the appropriate correlation coefficient to calculate is:

Just as in other tests of significance, sampling error when testing the statistical significance of correlation coefficients involves the use of theoretical sampling distributions with an assumed mean correlation of zero.

When two variables are at the ratio level of measurement, which of the following statements is true about calculating Pearson's r?

Phi should be used to calculate the correlation between variables at the ratio level of measurement.

Which of the following statements is correct regarding the table below?

Suppose as the number of abusive incidents increases, the severity of traumatic symptoms increases.This would be:

When a scatterplot is clearly curvilinear:

Why Study Statistics

Use of Statistics in Evidence-Based Practice

Review of Key Research Methodology Concepts and Terms

Frequency Distributions

Graphs and Charts

Measures of Central Tendency

Measures of Dispersion

Types of Distributions

Z-Scores, Percentiles and Effect Size

Probability and Sampling Distributions

Hypothesis Testing and Statistical Significance

Type I and Type Ii Errors

Interpreting the Strength and Importance of Relationships

The T-Test

Analysis of Variance

Cross Tabulation and Chi-Square

Regression Analysis

Applications to Single-System Evaluation Designs

Filters

Exam 17: Correlation

Pearson's r is best used with variables at the nominal level of measurement.

When there are many ties in the rank ordering of two ordinal variables, it is appropriate to calculate Kendall's tau-b.

When comparing the means of two or more categories of a nominal variable, we can use the eta statistic to depict the strength of the relationship.

Which of the following statements is correct about keeping or eliminating outliers when calculating the correlation coefficient?

A correlation of +.60 between quality of therapist-client relationship and the client's level of self-esteem means that improving the therapist-client relationship is likely to cause the client's self-esteem to improve.

Which of the following statements is correct regarding obtaining a correlation coefficient of zero?

A study finds a statistically significant correlation showing that the more treatment appointments missed by spouse abusers, the more abusive incidents.This means that:

A strong correlation between an independent and dependent variable indicates that the independent variable is a cause of the dependent variable.

A curvilinear scatterplot will usually be associated with a strong overall correlation coefficient.

A correlation of -.40 is stronger than a correlation of +.30.

A correlation of +.95:

In a study assessing the relationship between the number of close friends who drink alcohol regularly and the number of times a person in treatment for alcohol abuse drank alcohol after completing treatment, the appropriate correlation coefficient to calculate is:

When a correlation coefficient is near perfect:

In a study assessing whether experimental group participants spend fewer days incarcerated than do control group participants, the appropriate correlation coefficient to calculate is:

Just as in other tests of significance, sampling error when testing the statistical significance of correlation coefficients involves the use of theoretical sampling distributions with an assumed mean correlation of zero.

When two variables are at the ratio level of measurement, which of the following statements is true about calculating Pearson's r?

Phi should be used to calculate the correlation between variables at the ratio level of measurement.

Which of the following statements is correct regarding the table below?

Suppose as the number of abusive incidents increases, the severity of traumatic symptoms increases.This would be:

When a scatterplot is clearly curvilinear:

Why Study Statistics

Use of Statistics in Evidence-Based Practice

Review of Key Research Methodology Concepts and Terms

Frequency Distributions

Graphs and Charts

Measures of Central Tendency

Measures of Dispersion

Types of Distributions

Z-Scores, Percentiles and Effect Size

Probability and Sampling Distributions

Hypothesis Testing and Statistical Significance

Type I and Type Ii Errors

Interpreting the Strength and Importance of Relationships

The T-Test

Analysis of Variance

Cross Tabulation and Chi-Square

Regression Analysis

Applications to Single-System Evaluation Designs

Filters