Welcome to my home page! This website collects a few pages related to my research and teaching. It has six main sections dealing with courses in statistics and demography and with statistical software tutorials. These can always be reached via the links at the very top.
My main research interest is statistical demography, the development and application of statistical modeling techniques to the study of human population. My subject areas include fertility and health.
See the multilevel section for some of my work on multilevel models, including my papers with Noreen Goldman, and links to the datasets used in those papers, including both actual and simulated data.
The Handbook of Multilevel Analysis, edited by Jan de Leeuw and Erik Meijer, was officially published on Friday December 21, 2007. I contributed Chapter 9 on 'Generalized Linear Mixed Models'.
In other recent work I have looked at tempo effects in fertility and mortality, and have a paper in Demographic Research with a critical view of tempo adjustments in mortality estimation. The paper also appeared in a 2008 monograph edited by Barbi, Bongaarts and Vaupel which is available online.
Each fall I teach a course on generalized linear models, which covers regression models for continuous data (multiple regression, analysis of variance and analysis of covariance), for binary data (including logistic regression and probit models), for count data (Poisson, over-dispersed Poisson and negative binomial models) and for time to event or survival data (mostly piece-wise exponential hazard models using the Poisson-trick). We usually include a bit on log-linear models for contingency tables, but the last couple of years we substituted a week on models for longitudinal and panel data, including fixed and random-effects models.
The course website includes a set of lecture notes, available in pdf format as well as html, and a collection of Stata logs that show how to obtain every result in the notes using the popular statistical package Stata. Depending on the time of the year you also see problem sets and exams, with solutions. Sometimes I hear from students in remote corners of the globe who have found these materials useful.
Last spring I taught two half-semester courses, one on Survival Analysis and one on Multilevel Models. I taught these courses before in the Spring terms of 2005, 2008 and 2010, and the plan is to offer them every other year. The corresponding sections of the website, while less extensive than the section on GLMs, have a collection of handouts with emphasis on computation.
In the Spring of 2006 I taught Research Methods in Demography. The demography section of the website has handouts that use Stata to do demographic calculations organized under 12 different topics ranging from rates and standardization to stable populations. There are also four problem sets with solutions. I taught this course again in the Spring of 2008 but with substantially less emphasis on demographic computation, with all calculations done in Excel.
In my spare time I have developed the web software used since 2002 by the Population Association of America (PAA) to manage its annual meetings, including online submissions and reviews. The system has also been used by the International Union for the Scientific Study of Population (IUSSP), the European Association for Population Studies (EAPS), and the Union for African Population Studies (UAPS). I am particularly proud of the 2005 IUSSP site, which is available in English, French, and Spanish. All these sites run from the same code base (written in C#), using resource strings for localization.