Question 1

The correlation coefficient between two variables varies depending on their underlying units of measurement.

Accepted Answer

The correlation coefficient is a unitless measure that only depends on the covariance between two variables and their individual standard deviations. It does not vary with the units of measurement used for the variables.

Question 2

When determining the correlation coefficient,r,it does matter which variable is considered to be the dependent variable and which the independent.

Accepted Answer

The correlation coefficient, r, does not depend on which variable is considered to be the dependent or independent variable. The value of r remains the same regardless of the labeling of the variables.

Question 3

The product moment correlation is also referred to as regression correlation.

Accepted Answer

The product moment correlation is not the same as regression correlation. Although they are related, regression correlation represents the degree of relationship between the dependent variable and the independent variable in a regression analysis, while the product moment correlation measures the strength of the linear association between two variables in a non-directional way.

Question 4

The first step involved in conducting bivariate analysis is the development of a scatter diagram.

Accepted Answer

The first step in bivariate analysis is to develop a scatter diagram to visualize the relationship between two variables.

Question 5

The covariance may be either positive or negative.

Accepted Answer

The covariance measures the direction of the relationship between two variables. If the two variables tend to increase or decrease together, the covariance is positive. If one variable tends to increase while the other decreases, the covariance is negative. Therefore, the covariance may be either positive or negative.

Question 6

Regression analysis is concerned with the nature and degree of association between variables and does not imply or assume any causality.

Accepted Answer

Regression analysis is a statistical tool used to measure the relationship between two or more variables. It is primarily concerned with establishing the strength of the association between the variables and determining how well one variable predicts another. However, regression analysis does not necessarily establish causality, as the relationship between the variables could be due to other underlying factors that were not considered in the analysis.

Question 7

The r² statistic measures the proportion of variation in one variable that is explained by the other.

Accepted Answer

The r² statistic, also known as the coefficient of determination, measures the amount of variation in the dependent variable (Y) that is explained by the independent variable (X). It ranges from 0 to 1, where 1 indicates that all of the variation in Y is explained by X, and 0 indicates that none of the variation is explained by X. Therefore, r² does measure the proportion of variation in one variable that is explained by the other.

Question 8

Regression analysis is a statistical procedure for analyzing associative relationships between a metric dependent variable and one or more independent variables.

Accepted Answer

Regression analysis is indeed a statistical procedure used to analyze the linear associative relationship between a metric dependent variable and independent variables. It helps to understand how much of the variation in the dependent variable can be explained by changes in the independent variable(s).

Question 9

When r = 0,this means that X and Y are unrelated.

Accepted Answer

The answer of When r = 0,this means that X...

Question 10

A systematic relationship between two variables in which a change in one implies a corresponding change in the other is called covariance.

Accepted Answer

This is the definition of covariance, so it is true that a systematic relationship between two variables in which a change in one implies a corresponding change in the other is called covariance.

Question 11

According to the text,a scatter diagram is also known as a scattergram.

Accepted Answer

The text states that a scatter diagram is also known as a scattergram.

Question 12

A scatter diagram is a plot of the values of two variables for all the cases or observations.

Accepted Answer

A scatter diagram is indeed a plot of the values of two variables for all the cases or observations. It allows us to visually evaluate the relationship between the variables and identify any patterns or trends.

Question 13

Both r and r² are symmetric measures of association.In other words,the correlation of X and Y is the same as the correlation of Y and X.

Accepted Answer

This statement is true. The correlation coefficient (r) and the coefficient of determination (r²) both measure the strength and direction of association between two variables, and are symmetric measures. This means that the correlation between variable X and Y is the same as the correlation between variable Y and X.

Question 14

The final step involved in conducting bivariate analysis is significance testing.

Accepted Answer

Significance testing is often a part of bivariate analysis, but the final step typically involves interpreting the results and drawing conclusions based on the analysis.

Question 15

The test statistic for evaluating the null hypothesis associated with the product moment correlation is the F-test.

Accepted Answer

The test statistic for evaluating the null hypothesis associated with the product moment correlation is the t-test, not the F-test. The F-test is used for comparing variances.

Question 16

A procedure for deriving a mathematical relationship,in the form of an equation,between a single metric dependent variable and a single metric independent variable is called univariate regression.

Accepted Answer

The answer of A procedure for deriving a mathematical relationship,in...

Question 17

Questionnaire development is a step involved in conducting bivariate regression analysis.

Accepted Answer

Questionnaire development is not directly related to conducting bivariate regression analysis. It involves creating a set of questions that will be used to collect data for the research study. However, developing a good questionnaire can be beneficial in collecting accurate data for analysis.

Question 18

The correlation coefficient between two variables will be the same regardless of their underlying units of measurement.

Accepted Answer

The correlation coefficient measures the strength and direction of the linear relationship between two variables and is unitless. Therefore, it is not affected by the units of measurement of the variables.

Question 19

The covariance correlation is the most widely used statistic that summarizes the strength and direction of association between two metric variables.

Accepted Answer

The correct term is "correlation coefficient," not "covariance correlation." The correlation coefficient, such as Pearson's r, is used to summarize the strength and direction of the association between two metric variables.

Question 20

A statistic summarizing the strength of association between two metric variables is called the product moment correlation.

Accepted Answer

The product moment correlation is a commonly used statistic that measures the strength of association between two metric variables. It is also known as the Pearson correlation coefficient.

Quiz 18: Correlation and Regression