Multilevel Modeling of Non-Normal Data
A 2-Day Seminar Taught by Donald Hedeker, Ph.D.
Multilevel models are increasingly used for analysis of clustered and longitudinal data, and methods for continuous outcomes are commonly used and applied. However, many research studies have non-normal outcomes, for example, outcomes that are dichotomous, ordinal, or nominal. Although methods for such non-normal outcomes have been available for quite some time, they are perhaps not as routinely applied as models for continuous outcomes.
This workshop will focus on analysis of dichotomous, ordinal and nominal multilevel outcomes. Both clustered and longitudinal data will be considered, and the following models will be described: multilevel logistic regression for dichotomous outcomes, multilevel logistic regression for nominal outcomes, and multilevel proportional odds and non-proportional odds models for ordinal outcomes. The latter models are useful because the proportional odds assumption of equal covariate effects across the cumulative logits of the model is often unreasonable.
Who should attend?
If you plan on analyzing multilevel data (either clustered or longitudinal) and have categorical outcomes of interest, this course is for you. Analyzing multilevel categorical data is necessary in many research fields where normally distributed continuous outcomes are not obtained or relevant.
Participants should be thoroughly familiar with multiple linear regression, and have some knowledge of logistic regression.
In all cases, methods will be illustrated using software, with SAS, Stata, and SuperMix examples and syntax. Some familiarity with reading in data and performing basic statistical analyses in either SAS or Stata is recommended.
This is a hands-on course with at least one hour each day devoted to carefully structured and supervised assignments. To do the exercises, you will need to bring your own laptop computer with a recent version of SAS or Stata and the free student version of SuperMix installed. SuperMix can be downloaded at http://www.ssicentral.com/supermix/downloads.html. Power outlets will be provided at each seat.
NOTE: If you have Windows 7 or older, please run Supermix as administrator. Windows 8 and more recent should run as a regular user.
LOCAtions, Format, And Materials
The seminar meets Thursday, July 23 and Friday, July 24 at Temple University Center City, 1515 Market Street, Philadelphia, PA 19103.
The class will meet from 9 to 5 each day with a 1-hour lunch break.
Participants receive a bound manual containing detailed lecture notes (with equations and graphics), examples of computer printout, and many other useful features. This book frees participants from the distracting task of note taking.
Registration and lodging
The fee of $995.00 includes all seminar materials.
Lodging Reservation Instructions
A block of guest rooms has been reserved at the Club Quarters Hotel, 1628 Chestnut Street, Philadelphia, PA at a special rate of $127 per night. This location is about a 5 minute walk to the seminar location. In order to make reservations, call 203-905-2100 during business hours and identify yourself by using group code STA722. For guaranteed rate and availability, you must reserve your room no later than June 22, 2015.
- Introduction to multilevel analysis
- Multilevel analysis of clustered dichotomous outcomes
- Multilevel analysis of clustered ordinal outcomes
- Testing of the proportional odds assumption
- Multilevel non-proportional odds models for ordinal data
- Multilevel analysis of longitudinal dichotomous outcomes
- Subject-specific and population-averaged estimates
- Marginalization of the subject-specific estimates
- Multilevel analysis of longitudinal ordinal outcomes
- Multilevel analysis of longitudinal nominal outcomes