# Week3.pdf

There are two parts to this assignment. The first part is about correlationand regression analysis. The second part is about an independentsamples t-test analysis.

Part I: Correlation and Regression Analysis

Please open the file name personality.sav. In this exercise, you will focuson the relationship of two variables, beckdep (measure of depression)and emcontot (measure of emotional control). These variables are fromtwo instruments used in psychology, the Beck Depression Inventory,which is used to measure characteristics related to depression, and theCourtauld Emotional Control Scale (CECS), which is used to measuresubjective control of feelings of depression, anger, and anxiety inuncomfortable situations; this is a self-description instrument.

Imagine that you are interested in assessing the relationship betweenthese two instruments, with the goal of using the emcontot scores as apredictor of the beckdep scores.

1. In SPSS, calculate the Pearson’s correlation between beckdep andemcontot.

a. What are the null and alternative hypotheses?b. Present a scatterplot with beckdep scores in the Y-axis, and

emcontot in the X-axis.c. What type of relationship is depicted in the scatterplot,

positive or negative?d. Conduct the correlation analysis using the correlate menu in

SPSS.e. Report the results of the correlation analysis.f. What was the amount of variance shared by the two

variables?g. What is your decision regarding the null hypothesis based on

the results of the correlation analysis?

2. In SPSS, develop a regression model between the variablesemcontot and beckdep.

a. Which of these variables is the dependent (predicted)variable?

b. Conduct the regression analysis using the regression menuin SPSS.

c. What is the mean and standard deviation for emcontot andbeckdep?

d. What is the R-value? Is the value similar to the correlationcoefficient conducted above? If so, why do you think it issimilar?

e. What is the value of the R square? What does that value tellyou about the amount of variance predicted by emcomtot onbeckdep?

f. Was the model significant? How could you determine this?g. Report the results of the regression in the APA format.h. Develop the regression equation for the predicted variablei. Using the Regression equation developed above, please

estimate the Beck Depression Inventory score for anindividual who scores 2.50 in the emcontot (CECS).

Part II: t – test Analysis

For Part II, you are now interested in examining differences in the BeckDepression Inventory score exist between individuals who are marriedand not married. In order to determine if differences exist, you will usethe variable name marital as the independent variable and beckdep asthe dependent variable.

Once you examine the variable marital, you realize that the variableincluded six different categories. Therefore, the variable needs to berecoded in two categories, single (including separated, divorce, orwidowed) and married; because the independent samples t – test is usedto compare differences between two groups.

In SPSS, conduct an independent samples t – test:

1. Conduct the independent samples t – test, including theassumptions tests.

2. There are three main assumptions needing to be satisfied beforeusing the independent-samples t – test for testing differencesbetween the genders. Use SPSS to generate the output needed totest the assumptions. Please discuss each one and explainwhether each has been met using SPSS output as needed toinclude the Shapiro-Wilk test for normality (used when the samplesize is less than 50), histograms, and the Levene’s test.Remember, if the population value is unknown, it is permissible toinfer from sample values. Regardless of sample size, test whetherthese 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 in APA format.8. What might be concluded from this hypothetical study? (Hint: The