Part 1: Correlation and Regression Analysis

Please open the file name personality.sav. Focus on the relationship of two variables, beckdep (a measure of depression), and emcontot (measure of emotional control using the Courtauld Emotional Control Scale [CECS]). Two instruments used in psychology are the Beck Depression Inventory, which is used to measure characteristics related to depression; and the CECS, which is used to measure subjective control of feelings of depression, anger, and anxiety in uncomfortable situations; this is a self-description instrument.

Scenario:

You are interested in assessing the relationship between these two instruments, with the goal of using the emcontot scores as a predictor of the beckdep scores.

1. In SPSS, calculate the Pearson's correlation between beckdep and emcontot.
2. What are the null and alternative hypotheses?
3. Present a scatterplot with beckdep scores in the Y-axis, and emcontot in the X-axis.
4. What type of relationship is depicted in the scatterplot, positive or negative?
5. Conduct the correlation analysis using the correlate menu in SPSS.
6. Report the results of the correlation analysis.
7. What was the amount of variance shared by the two variables?
8. What is your decision regarding the null hypothesis based on the results of the correlation analysis?
9. In SPSS, develop a regression model between the variables emcontot and beckdep.
10. Which of these variables is the dependent (predicted) variable?
11. Conduct the regression analysis using the regression menu in SPSS.
12. What is the mean and standard deviation for emcontot and beckdep?
13. What is the R-value? Is the value similar to the correlation coefficient conducted above? If so, why do you think it is similar?
14. What is the value of the R square? What does that value tell you about the amount of variance predicted by emcomtot on beckdep?
15. Was the model significant? How could you determine this?
16. Report the results of the regression
17. Develop the regression equation for the predicted variable
18. Using the Regression equation developed above, please estimate the Beck Depression Inventory score for an individual who scores 2.50 in the emcontot (CECS).

Part 2: t-test Analyses

Scenario

You are now interested in examining differences in the Beck Depression Inventory score exist between individuals who are married and not married. In order to determine if differences exist, you will use the variable namemaritalas the independent variable, and beckdep as the dependent variable. Once you examine the variable marital, you realize that the variable included six different categories. Therefore, the variable needs to be recoded in two categories, single (including separated, divorce, or widowed) and married; because the independent samples t-test is used to compare differences between two groups.

In SPSS, conduct an independent samples t-test:

1. Conduct the independent samples t-test, including the assumptions tests.
2. There are three main assumptions needing to be satisfied before using the independent-samples t-test for testing differences between the genders. Use SPSS to generate the output needed to test the assumptions. Please discuss each one and explain whether each has been met using SPSS output as needed to include the Shapiro-Wilk test for normality (used when the sample size is less than 50), histograms, and the Levene's test. Remember, if the population value is unknown, it is permissible to infer from sample values. Regardless of sample size, test whether these assumptions are met.
3. What are the null and alternative hypotheses?
4. What is the mean of the Beck Depression Inventory for the single and married groups?
5. What is the value of t?
6. What is the associated probability?
7. Report the results
8. What might be concluded from this hypothetical study?