SC 704: Topics in Multivariate Statistics Fall 2012 Monday/Wednesday 1:30 – 2:45 pm O’Neill 245 Professor: Sara Moorman Office: 404 McGuinn Hall Office hours: Mondays 10:15-11:15; Wednesdays 3:00-4:00 E-mail: moormans@bc.edu Phone: (617) 552 - 4209 About the Course This applied course is designed for students in sociology, education, nursing, organizational studies, political science, psychology, or social work with a prior background in statistics at the level of SC703: Multivariate Statistics. It assumes a strong grounding in multivariate regression analysis. The major topics of the course will include OLS regression diagnostics, binary, ordered, and multinomial logistic regression, models for the analysis of count data (e.g., Poisson and negative binomial regression), treatment of missing data, and the analysis of clustered and stratified samples. All analyses in the course will be conducted using Stata, but no previous Stata experience is necessary. Readings Required textbooks: Enders, Craig K. 2010. Applied Missing Data Analysis. ISBN: 9781606236390 Long, J. Scott. 1997. Regression Models for Categorical and Limited Dependent Variables. ISBN: 0803973748 Long, J. Scott and Jeremy Freese. 2006. Regression Models for Categorical Dependent Variables Using Stata. 2nd ed. ISBN: 1597180114 Recommended textbook: Acock, Alan C. 2010. A Gentle Introduction to Stata. 3rd ed. ISBN: 1597180750 Course reserves online: Access “*” entries as .pdf files through the library website (http://www.bc.edu/libraries/) or through the link on the course Blackboard page (https://cms.bc.edu/webct/entryPageIns.dowebct). SC 704 Topics in Multivariate Statistics page 2 of 6 Software This course requires the use of the program Stata. The most current version is available on the computers in the Sociology graduate student lounge. For use on your own computer, you have two options: (1) access the program through remote connection to apps.bc.edu, or (2) purchase the program through BC’s Research Services. Ask your department administrator about Campuswide GradPlan. Prices start at $32 (price for a six-month student license). Assessment Grading scale A 93 – 100% B 83 – 86% F 0 – 59% Task Article critique Project update I Project update II Peer review Presentation Final paper draft AB- 90 – 92% 80 – 82% Due date Weekly, see schedule (N = 10) October 15 November 14 November 26 December 3, 5, or 10 December 17 B+ C 87 – 89% 60 – 79% Percentage of grade 10 at 3% each: 30% 5% 5% 5% 25% 30% Article Critique For each week, I’ve selected a recent publication from a major sociology journal that uses the method we’re covering in class that week. You should read the article, and then complete two tasks: (1) Outline the analysis: What are the hypotheses or research questions, and how did the authors go about testing them statistically? (2) Critique the article: Make a list of what you think the authors did well and what they did poorly. Specific questions to consider include: Does this analysis best answer the research question given the data the researchers had available, or is there a discrepancy between the research question and its empirical operationalization? Would you have chosen different statistics instead of or in addition to the statistics employed? Were you left with any critiques of the data or methods, or did the authors anticipate your concerns? If you had the data at hand, would you be able to replicate the analysis? Were the results interpreted clearly and correctly? Were the results presented effectively in tables and/or figures? Are the interpretations fair, or do they seem to go beyond what the data can really support? The purpose of this exercise is to prepare to discuss the article in class, so be sure to outline and list rather than write an essay. You’ll submit your outline and list to receive credit. I will simply note whether your work is complete or incomplete rather than judge the content of your responses, so don’t worry if you don’t understand every last thing the authors did. Bring your questions to class and we’ll work them out. Research Project (More detail on each step to follow later in the semester) I find that the best way to learn statistics is to practice them on real data that mean something to you. Therefore, the major product of this course will be a journal-style research article (i.e., 20- SC 704 Topics in Multivariate Statistics page 3 of 6 35 pages in length, including the standard sections: title page, abstract, introduction, methods, results, discussion, references, tables/figures). The article is required to include two or more of the methods covered in class from September 19 onward. For example, you might run (a) a test of mediation in a complex survey dataset, or (b) one outcome that requires binary logistic regression and a second that requires Poisson regression, or (c) a multinomial logistic regression on multiply-imputed data. Neither using Stata for your analyses nor testing a simple OLS regression model “count” towards your two methods. In mid-October and mid-November you will submit written “updates” that will be drafts of sections of the paper. For instance, for one update you might submit the introduction and methods sections, and for the next update you might submit the results and discussion sections, or you might want me to look at revisions of your introduction and methods sections. Precisely what you turn in will be up to you, although I’m happy to make recommendations on a case-bycase basis. Updates have two purposes: (a) to ensure that you pace your work throughout the semester, rather than try to write the whole paper the night before it is due, and (b) to provide opportunities for my feedback on your work. As such, updates are required but not graded. If you turn one in, you will receive full credit. It is all right if every last thing you have done in the update is wrong, so please do not hide or avoid things you are uncertain about. The updates are precisely the time for us to find those problems and fix them, not the time for me to assess your work for a grade. You will also exchange your second update with a classmate and complete peer reviews for one another. I’ll match you up later in the semester based on the similarity of your topic, data, or methods. Finally, you’ll give a conference-style presentation of your project in class, and about a week later, submit your completed paper. Although it’s certainly not a requirement, you should seriously consider using this project as an opportunity to meet a degree requirement (e.g., area exams), prepare a conference presentation, and/or develop a submission for publication. If you’re already working on a project, I encourage you to use this course to develop it. If you’re starting from scratch, many datasets are publicly available from universities and government agencies, and many more are available to researchers through BC’s subscription to the Inter-University Consortium for Political and Social Research (ICPSR) at the University of Michigan. Be aware that the deadline to submit a paper for presentation at ASA 2013 in NYC will be in mid-January, and your course paper will fit their submission criteria. Submitting Your Work x You should bring hard copy of your article critiques to class on their due dates. They are due at 2:45 pm. x You should e-mail me the updates and final draft of the research project as Word documents. I’ll use the track changes function to give you feedback. They are due at 11:59 pm on their due dates. x I’ll give you details later regarding what materials I need and how/when you should submit them for the peer review and presentation assignments. x I will not accept late work. If you have a conflict with a deadline, then make arrangements with me well ahead of time. SC 704 Topics in Multivariate Statistics page 4 of 6 Academic Honesty Your work must be your words and ideas. When writing papers, use quotation marks around someone else’s exact words and identify whose words they are. If you come across a good idea, by all means use it in your writing, but be sure to acknowledge whose idea it is. Do not allow another student to copy your work. Failure to comply will result in (a) automatic failure of the assignment, and (b) a report to the Dean and the Committee on Academic Integrity. For further information, please review the College’s policies on academic integrity here: http://www.bc.edu/offices/stserv/academic/resources/policy.html#integrity Schedule Date Topic September 5 Using Stata September 10 Locating and using data for secondary research Ordinary least squares (OLS) regression: Review and diagnostics Ordinary least squares (OLS) regression: Review and diagnostics Complex survey data September 12 September 17 September 19 September 24 September 26 Complex survey data Mediation October 1 Mediation October 3 Moderation October 8 NO CLASS: Columbus Day Reading Due x Long chapter 2 x Long & Freese chapters 1-3 x Choi and David* x x x x Johnson and Elliott* Kreuter and Valliant* Reynolds and Johnson* Winship and Radbill* Choi and David x x x x Baron and Kenny* Flippen* Hayes* MacKinnon, Fairchild, and Fritz* Reynolds and Johnson x Fairchild and McQuillin* x Stets and Carter* x Wu and Zumbo* Flippen SC 704 Topics in Multivariate Statistics Date Topic October 10 Moderation October 15 Missing data October 17 Missing data October 22 Multiple imputation October 24 October 29 Multiple imputation Binary outcomes October 31 Binary outcomes November 5 Ordinal outcomes November 7 Ordinal outcomes November 12 Nominal outcomes November 14 NO CLASS November 19 Nominal outcomes November 21 November 26 NO CLASS: Thanksgiving Count data November 28 Count data page 5 of 6 Reading Due x Enders chapters 1, 2, and 10 x Hallerd* Stets and Carter; Update 1 x Enders chapters 7, 8, and 9 x Silver, Silver, Siennick, and Farkas* Hallerd x Kim and Pfaff* x Long chapter 3 x Long & Freese chapter 4 Silver, Silver, Siennick, and Farkas x Cech, Rubineau, Silbey, and Seron* x Long chapter 5 x Long & Freese chapter 5 Kim and Pfaff x Long chapter 6 x Long & Freese chapters 6 and 7 x McCammon* Cech, Rubineau, Silbey, and Seron Update 2 x Long chapter 8 x Long & Freese chapter 8 x Warner, Manning, Giordano, and Longmore* McCammon; peer review SC 704 Topics in Multivariate Statistics Date Topic December 3 Class presentations December 5 Class presentations December 10 Class presentations December 17 Reading page 6 of 6 Due Warner, Manning, Giordano, and Longmore Final paper