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PowerPoint for Regression Analyses
Powerpoint for Factor Analysis
Assignments for PSY6010 include weekly readings, with a statistical problem, which must be performed and results interpreted. SPSS Syntax and output must be provided. Please copy the spss table and paste it into the word document as a picture.
Using the Employee Survey, do the following exercises. 1. Our research question is: What is a good job? Explain why this is important (1 paragraph). Provide an example of a client. Select a measure of job satisfaction and explain why you think it.s a good one. (1 paragraph) Provide a set of factors that you think would determine job satisfaction. First discuss them as concepts, and then discuss the measurements of them. (1-2 paragraphs) 2. Using your measure of job satisfaction: Run a frequencies test, with mean and standard deviation. Run a frequencies test on all the IVs. Explain what your results mean for your potential analysis: will these variables work? 3. Do a compare means for your dependent variable and a dichotomous IV. Check the anova option. Then run a One-Way Anova (from Compare Means) Explain your results. 4. Run a correlation of your dependent variable and 3 other independent variables. Explain your results. 5. Try a simple regression: use only interval or continuous variables as IVs for this exercise. Explain your results. What do you conclude from your simple model? How might you go about improving it? Include your syntax and output with your explanation.
Using the Employee Survey, do the following exercises. 1. Run a crosstab of overall job satisfaction and .challenged and interested in my work.. Are there any logical outliers? Describe and explain how you might go about handling them. 2. For the missings in overall job satisfaction, replace them with the mean, and create a dummy variable for missing. 3. Change the string variable for race into a dummy variable for whites versus everyone else. 4. Change age (v54) into a numeric variable. Recode the values to the midpoint value. 5. Run a compare means for sufficient opportunity for career advancement by How long you.ve worked in this company (Tenure). Conduct a linearity check as well. Would you use tenure as an explanatory variable for career advancement perception? Why or why not? 6. Now try this with hours worked each week instead of tenure. Would you use hours worked as an explanatory variable? Now transform hours worked to 51 hours or more versus less. Explain why you might do this. Run the compare means again. What are the differences and what does that tell you about hours worked and career advancement attitudes? 7. Run a correlation of v20-v25. Is there evidence of multicollinearity? How would you address this if using these variables to explain overall job satisfaction? What would you do and then, make the variable changes, if any. Extra credit: Calculate a variable for how long it took to complete the survey (start date versus end date). What are the outliers? Include your syntax and output with your explanation.
Using the Employee Survey, do the following exercises. 1. Choose a dependent variable that is amenable to be used as a dependent variable in a regression. 2. Select two other continuous, interval or ratio variables (scale) as independents, and one dichotomous variable. 3. If the correlation is above .65 for any independent variable, choose another. 4. Explain your research question as done in the PowerPoint, develop the model and hypotheses, and write up your methods section. 5. Run the regression using the standard method. 6. Write up your results and interpretation. 7. Calculate two different levels of your dependent variable by slotting in different values of the IVs. Include your syntax and output with your explanation.
1. Create an interaction term by computing a new variable COMPUTE NEWVAR = oldvar1 * oldvar2.
2. Run an OLS regression where Y = your dependent variable (continuous, scale or interval) and x1 = one variable,
x2 = the second. y = a + b1x1 + b2x2.
3. Now run the regression adding in the interaction term as well interaction = x1*x2.
y = a + b1x1 + b2x2 + b3interaction.
4. interpret the differences in the two models.
Using the Employee Survey, do the following exercises. 1. Using one of the non-categorical variables as the dependent variable. Create a conceptual and hypothesized model, explaining your variables and method. 2. Run a regression with two dichotomous variables and one ratio or interval variable. 3. Calculate an interaction term with the two dichotomous variable and rerun the regression, providing logic for the interaction. Did it significantly contribute to the model? Explain what the result means. 4. Now calculate an interaction term for the dichotomous and the non-categorical variable, providing logic for this interaction. Run the regression. Explain the results. Include your syntax and output with your explanation.
Your homework is to do the assigned reading re: logistic regression (chapter 6A and 6B) Begin to use your dataset for your project by downloading a dataset or obtaining the data from me, and submitting the codebook to me for the assignment. Here is a link to instructions for working with a data set from the SDA archive. If you don't have another data set at this point, then you MUST use the GSS. However, if you do, then it's time to show me what you have and by that I mean a codebook with lists the variables you will use in your models (proposed), the question text, the number of cases, and frequencies for all values.
Using our Employee Survey, do the following exercises. A. 1. Identify a research question you want to explore where the DV will be a dichotomous variable. Identify 2 dichotomous independent and 1 interval independent variable, and state your hypotheses. 2. Conduct diagnostics.chi-square tests for the dichotomous IVs and compare means for your interval IV. Are your hypotheses supported? 3. Run a logistic regression with your variable and 2 dichotomous independent and 1 interval independent variable 4. Explain your results: the B coefficients, the Exp(B) (odds ratios), their statistical significance, and the model fit. 5. Interpret these results. B. Using your custom GSS data set, explain your conceptual model and how you.ve operationalized it. You will need to consider identifying multidimensional scale items for collapsing using either factor analysis, or some other variable transformation (don't worry about FA yet, we haven't covered it.) Include your syntax and output with your explanation.
Using our Employee Survey, or your own dataset, do the following exercises. 1. Identify a dependent variable suitable for ordinal logistic regression, and one suitable for multinomial logistic regression. Explain briefly. 2. Conduct diagnostics, that is, crosstabs with the chi-square tests for the dichotomous IVs and compare means for your interval IV with the anova. Do we see evidence of group definition? 3. Run the ordinal logistic regression and multinomial logistic regression for your respective DVs. Use the same independent variables if you wish. Explain your results: 4. Interpret these results. Include your syntax and output with your explanation.
1. Run the frequencies for all the variables you'll be using in your model.
2. Run a correlation of your dv(s) with your iv's.
3. Try out a very simplistic version of your model.
4. Describe your results.
This powerpoint will be used in class on April 7 and April 14: Powerpoint for Factor Analysis
Also for April 21 - The MIDTERM!
Read Schwab, Chapter 15 and 21.
Bring with you (at least) the methods section of your paper. We will be discussing them in class. Use the aforementioned
chapters as a guide. Also, here is a
document that
summarizes requirements for writing research papers.
Bring with you the articles we've read this year and be prepared to discuss how they've presented the results.
People will be presenting their work. Everyone will have a 20-30 minute
presentation using powerpoint. The numbers in parentheses are suggested
number of slides for each section.
IN it you will state your research questions (1), what it's important,
a little background (1-2), your hypotheses (1-2),
your results as they are now (2-3), and your discussion (1) conclusions (2).
Be prepared for questions from your classmates.
FINAL PAPER DUE BY JUNE 30!!!