Microsoft Word - homework8_215_F2020 SOC / PSY 215 Homework #8 Spring 2020 30 points Due Tuesday, April 28, between 800am and 10:00am. 1. You are a graduate student who is examining the question of whether adolescent delinquency could be explained by certain early experiences in the lives of youth. You decide to use Add Health data to explore the relationship between delinquency and the age at which a youth may have smoked their first whole cigarette. Adolescent delinquency has been measured by summing the 15 delinquency variables in section 28 of the Add Health study. Your smoking variable comes from S28Q2, which ranges in value from 0 (never smoked a whole cigarette) to 20 yrs of age. (Respondents who never smoked were also coded as “0”). You conduct a linear regression analysis using SPSS and generate the following results: Model Summary Model R R Square Adjusted R Square Std. Error of the Estimate 1 .309a .095 .095 5.13782 a. Predictors: (Constant), S28Q2 AGE-SMOKED AN ENTIRE CIGARETTE-W1 Coefficientsa Model Unstandardized Coefficients Standardized Coefficients t Sig. B Std. Error Beta 1 (Constant) 2.994 .185 16.158 .000 S28Q2 AGE-SMOKED AN ENTIRE CIGARETTE-W1 .254 .022 .309 11.564 .000 a. Dependent Variable: delinq Please answer the following questions: A. In the “Model Summary” box, you’ll see a value for Adjusted R Square. i) The range of values that are possible for Adjusted R Square are 0 to 1. What would it mean if you saw a value of zero reported here? ii) What would it mean if you saw a value of 1 reported here? iii) Please provide an accurate interpretation of the actual value of Adjusted R Square reported by SPSS. B. Explain the difference between a “dependent” variable and an “independent” variable. In the research performed above, which variable is the “dependent” variable? C. SPSS provides two different solutions to your question. One solution is offered in standard deviation units, and the other solution is reported in raw (unstandardized) units. If the equation of a regression line is Y = a + b(X), what is the solution SPSS gave you in standard deviation units? D. Now, write out the solution SPSS gave you in raw (unstandardized) units. a. In this unstandardized equation, what does the value 2.994, associated with the constant, represent? b. What does the value .254, associated with the independent variable, represent? E. OK, now here are two “tricky” questions that you should nevertheless be able to answer if you understand the equation SPSS is giving you in unstandardized units. i. If a respondent smoked their first cigarette at age 16, what is the expected number of delinquent acts the respondent would report? ii. What is the expected difference in the number of delinquent acts between any two respondents who differ by 5 years in the age at which they smoked their first cigarette? (Your answer would be the same whether the kids are aged 11 and 16, or 13 and 18, or 7 and 12.) 2. Please use SPSS to analyze our Add Health data and evaluate the effect of adolescent depression on the desire of a youth to go to college. Copy and paste your “model summary” and “coefficients” results produced by the procedure (i.e., the same types of output I provided for you in Q1). Then, answer the following questions (Most are similar to the questions in Q1, but some are different, so please read carefully.) Please answer the following questions: A. In the “Model Summary” box, you’ll see a value for Adjusted R Square. i) The range of values that are possible for Adjusted R Square are 0 to 1. What would it mean if you saw a value of 1 reported here? ii) Please provide an accurate interpretation of the actual value of Adjusted R Square reported by SPSS. B. Explain the difference between a “dependent” variable and an “independent” variable. In the research performed above, which variable is the “independent” variable? C. SPSS provides two different solutions to the question. One solution is offered in standard deviation units, and the other solution is reported in raw (unstandardized) units. i. If the equation of a regression line is Y = a + b(X), what is the solution SPSS is giving you in standard deviation units? Why is SPSS not providing you with the value of “a”? ii. Now, write out the solution to the regression line SPSS is giving you in raw (unstandardized) units. D. In this unstandardized equation, what does the value associated with the constant? What does it mean? E. In the unstandardized equation, what is the coefficient associated with the independent variable? Please provide an interpretation of this value. F. OK, now here are two “tricky” questions that you should nevertheless be able to answer if you know the equation SPSS is giving you in unstandardized units. a. If a respondent has a depression score of 9, what is the expected value they should have for “what to go to college?” b. What is the expected difference in the value of “want to go to college” between any two respondents who differ in their depression scores by 6?