MODULE 5 - SELF TEST 1. When interested in examining how one variable changes in relation to another, which of the following descriptive statistics would you want to use? a. Mean b. Variance c. Correlation d. Standard deviation 2. A correlation coefficient can range in value. Which of the following illustrates this range? a. -.01 to .01 b. -1.0 to 1.0 c. -2.0 to 2.0 d. -3.0 to 3.0 3. If variables change in the same direction, what type of correlation is this called? a. Positive correlation b. Negative correlation c. Positive causation d. Negative causation 4. If variables change in the opposite direction, what type of correlation is this called? a. Positive correlation b. Negative correlation c. Positive causation d. Negative causation 5. The correlation between variable X and variable Y is represented by which of the following? a. RA(xy)2 b. rxy c. rx(y) d. Rx/y 6. Which of the following represent the Excel function to be used when computing correlation coefficients? a. CORREL(A:10; B:10) b. CORREL(A:1-10; B:1-10) c. CORREL(A1:A10, B1:B10) d. CORREL(A10:B10) 7. What would you use to represent a correlation visually? a. Histogram b. Polygon c. Line graph d. Scatterplot 8. When data points group together in a cluster from the lower left-hand side of the xy axis to the upper right-hand side, what is this? a. Negative slope b. Positive slope c. Negative intercept d. Positive intercept 9. If the correlation between variables is .70, what percent of the variance is shared variance? a. 70% b. 30% c. 49% d. 51% 10. If the correlation between variables is .80, what is the coefficient of determination? a. .20 b. .36 c. .64 d. .80 11. Which of the following correlations would be interpreted as a very strong relationship? a. .80 b. .70 c. .60 d. .50 12. If you wanted to compute the correlation between two interval-level variables, which type of correlation should you use? a. Point biserial b. Phi c. Spearman rank d. Pearson 13. If you wanted to compute the correlation between two nominal-level variables, which type of correlation should you use? a. Point biserial b. Phi c. Spearman rank d. Pearson 14. If you wanted to compute the correlation between two ordinal-level variables, which type of correlation should you use? a. Point biserial b. Phi c. Spearman rank d. Pearson 15. If you wanted to compute the correlation between one nominal-level variable and one intervallevel variable, which type of correlation should you use? a. Point biserial b. Phi c. Spearman rank d. Pearson 16. What is the most important characteristic of a correlation coefficient? a. Sign b. Absolute value c. One-tailed d. Two-tailed 17. Which of the following is an example of a research hypothesis for testing a correlation coefficient? a. H1: rxy does not equal 0 b. H1: rxy equals 0 c. H0: rxy equals 0 d. H0: rxy does not equal 0 18. The level of risk or Type I error typically set for testing the level of significance of a correlation coefficient is which of the following? a. .01 b. .50 c. .05 d. .10 19. Which of the following represents the test statistic for a correlation coefficient? a. p b. F c. t d. r 20. Which of the following is another use for correlation coefficients? a. Testing mean differences b. Testing causal relationships c. Estimating reliability d. Estimating power 21. If the correlation between two variables is .496, how much of the variance has not been accounted for? a. 24.6% b. 49.6% c. 50.4% d. 75.4% 22. What statistical technique is used to make predictions of future outcomes based on present data? a. Analysis of variance b. Repeated measures c. Linear regression d. Correlational analysis 23. Which of the following is used to illustrate the \"best guess\" as to the predicted Y variable score based on X? a. Regression equation b. Scatterplot c. Standard error of the estimate d. Regression line 24. What is another name for a regression line? a. Line of best fit b. Scatterplot line c. Line graph d. Line of the estimate 25. Which of the following symbols is associated with the independent variable in the regression equation? a. X b. Y c. a d. b 26. In regression, the criterion variable is also known as the ____________. a. Independent variable b. Dependent variable c. Predictor variable d. Correlated variable 27. A positive trend line is associated with what type of slope? a. Negative slope b. Direct slope c. Positive slope d. Nondirectional slope 28. Which of the following is like a standard deviation for all error scores in regression? a. Error of the estimate b. Error standard deviation c. Standard error of estimate d. Precision of error