PubH 6052 FINAL EXAM PubH 6052 FINAL EXAM Please answer the following questions to the best of your ability on this document and upload it as a PDF on the 2GW online platform. Make sure that your name appears on your submission (see instructions on the Final Exam page in the Assignments section)....

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Please answer the following questions to the best of your ability on this document and upload it as a PDF on the 2GW online platform. Make sure that your name appears on your submission (see instruc... tions on the Final Exam page in the Assignments section). You may use your notes, your book, or any other fixed written sources as you work on this. But please work alone on this assignment, and direct any questions or concerns to your course director or section leader. Good luck! 1. What is a codebook? Who might create one, what would she or he include in it, and what purpose or purposes would it serve? A codebook is a separate document such as a Word document or Excel spreadsheet that stores all the critical information about the data. It includes the variables, name of the variables, a brief description of the variables, questionnaire items, a sentence explaining what each variable represents, and an explanation of each numerical code. A codebook serves as a record that we can refer to if we cannot remember what was in the dataset. 2. Explain the distinction between variable labels and value labels in an electronic dataset. Variable labels describe what that variable is or what it represents. Value labels describe coded data (numbers) within a variable. For example, education levels could have the variable label “Education,” and the values labels would describe the numbers associated with a certain level of education. 3. True or False: The linear regression model cannot handle curvilinear relationships between independent and dependent variables. False 4. True or False: By convention, if we conduct a statistical hypothesis test and obtain a p-value of .3, we would reject the null hypothesis. True 5. Suppose you have two SPSS datasets. The first contains the variables ID, X1, X2, and X3 for participants 1 through 100; the second contains the variables ID, X4, X5, and X6 for the same 100 participants. Suppose that the datasets are named EvalPre.sav and EvalPost.sav, and are saved on your computer in following file location: C:\Documents and Settings\Evaluation\EvalData\ And suppose, finally, that you want to combine these datasets to create a new dataset, to be named EvalPrePost.sav, containing ID and X1 through X6 for all 100 participants. What SPSS syntax would you use to accomplish this? I would open EvalPre.sav and use Star Join to add EvalPost.sav with this syntax: STAR JOIN /SELECT t0.ID, t0.X4, t0.X5, t0.X6 /FROM * AS t0 /JOIN ‘C:\Documents and Settings\Evaluation\EvalData\EvalPost.sav' AS t1 ON t0.id=t1.id /OUTFILE FILE=*. 6. A research team is studying cognitive decline in old age. They collect data on 300 people between the ages of 75 and 95 years. One of the key variables is a measure of one particular aspect of cognitive functioning: Executive function (named EXFUNC in the dataset). For this study it is measured using a test that produces values ranging from 0 to 100, with higher values representing better executive function. The investigators fit a linear regression model to their data and obtain the following estimated model: [Show More]

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