Statistics 4F03/6F03

Categorical Data Analysis

Dr P.D.M. Macdonald

2006-2007

Announcements

Calendar Description & Course Outline

STATS 4F03/6F03: Categorical Data Analysis

Two-way and three-way contingency tables, logistic regression, loglinear models for contingency tables, collapsibility, ordinal associations, multicategory logit models.

Course Outline

Timetable

Monday 12:30, Tuesday 13:30, Thursday 12:30 in UH-103

Textbooks

Agresti, A. (2002) Categorical Data Analysis, Second Edition, Wiley.
This is an expanded edition of the 1996 text.

Agresti, A. (1996) An Introduction to Categorical Data Analysis, Wiley.

Dobson, A.J. (2002) An Introduction to Generalized Linear Models, Second Edition, Chapman & Hall.
This text gives very a accessible account of the theory and is aimed at anyone who needs to use GLMs to analyse data.

Bishop, Y.M.M., Fienberg, S.E. & Holland, P.W. (1975) Discrete Multivariate Analysis, Theory and Practice, MIT.
This is the first major monograph on the subject; the notation and some of the methods are outdated but the data sets and discussions are excellent.

Course Notes

• Exact Methods for Odds Ratio in a 2 x 2 Table
• R Functions for ROC Curves and the Hosmer-Lemeshow Test

Computing Resources

• R for Beginners - a 31-page introduction to R, in pdf format - and other online manuals
• Download R - an open code language and environment for statistical computing, distributed free of charge, available for unix, Windows, Macintosh, and Linux.
  You want the "Precompiled binary distribution", not the "source code". For Windows installation, go to the link for "Windows (95 and later)", open folder "base", and click on R-2.3.1-win32.exe to download the installer. Run R-2.3.1-win32.exe to install R on your computer.
• An Online Splus Tutorial from Dalhousie University

Assignments

• Assignment #1 - Due 2006-10-02 12:30
  • Hints: Drawing ellipses in R; Drawing confidence regions.
• Assignment #2 - Due 2006-11-13 12:30
  • Problems from Agresti (2002): 2.12, 2.18, 2.27, 2.35, 3.4, 3.11, 3.13, 3.31.
• Assignment #3 - Due 2006-12-04 16:30
  • The handout Exact Methods for Odds Ratio has many examples where nlm() is used to minimize a function or solve an equation. For each example, draw a graph that shows the function and the solutions. Also, in some of the examples the fitted odds ratio is infinite; in these cases, rearrange the table so that the odds ratio is 0 and re-do the analysis.
  • Cancer survival data from Bishop, Fienberg & Holland, Section 3.7, log-linear and logistic analysis.
  • Mantel-Haenszel example from Rosner, Section 13.5, log-linear and logistic analysis.
  • Horseshoe crab data from Agresti (2002), Table 4.3. You can find the data online. Do a loglinear analysis with the response variable the number of satellites and a logistic analysis with binary absent/present response. You may find ROC curves and the Hosmer-Lemeshow test useful.

Tests

Test #1	2006-10-12 (Thursday)	18:00-20:00	BSB-241 Student Technology Centre*
Test #2	2006-11-14 (Tuesday)	13:30	Take-home test due 2006-11-20 12:30

Aids permitted: Open book.

*You must have a valid userid, password and laser printing account for the BSB Student Technology Centre. Tests MUST be submitted on paper; electronic submission is NOT permitted.

If you are unable to write a test at the scheduled time, please e-mail me at least 3 days before to make special arrangements.

Final Exam

The problems are from Agresti (2002). You may use any resources but you may not communicate with anyone other than the instructor. Your completed work must be submitted to me by 9 am on Thursday December 14.

Problems 3.40, 3.42, 3.43, 4.13.
Analyse the data in Table 6.9 on p. 230.

Some Other Links

• My work on mixture distributions
• Statistical Society of Canada / Société statistique du Canada

Need more help?

• If you have concerns about preparing for tests and examinations, improving your study habits, giving class presentations, or mastering English as a second language, the Centre for Student Development can help.