-gologit2- is a user-written program that estimates generalized logistic regression models for ordinal dependent variables. The actual values taken on by the dependent variable are irrelevant except that larger values are assumed to correspond to "higher" outcomes. A major strength of -gologit2-...

Efficient data cleaning and management is critical to the success of any large research project. This is particularly true in the case of longitudinal studies and/or those in which the data management tasks are shared among many individuals. Faced with several such projects, we developed a...

While scales are an integral part of the measurements involved in many research projects, few researchers make the effort to ensure that these scales are valid, reliable, uni-dimensional and consistent with relevant correlates. This presentation outlines how the Stata routine –optifact- can be...

In a *nix-based environment such as Mac OSX it is very simple to set up 'cron jobs' that run at any periodic interval. This presentation illustrates how 'cron', the perl scripting language and Stata are used to generate a database of daily stock quotes from a regional index, compute an investor...

Mata is both an interactive environment for manipulating matrices and a full development environment that produces compiled and optimized code. This talk will cover both applications, with an emphasis on how you can use Mata to quickly program solutions and how you can easily create new Stata...

This talk discusses Stata's features for analyzing survey data and correlated data, and will explain how and when to use the three major variance estimators for survey and correlated data: the linearization estimator, balanced repeated replications, and the clustered jackknife (the latter two...

In this presentation we shall address two issues concerning the research process: (1) the need for an efficient way to transfer results obtained using a statistical package into a written report, and (2) the need to organize and to package one's work so that those results are easily...

Note: I hesitate somewhat to propose this session due to the general disdain that many feel toward word processors, so you should feel free to reject it or accept it if you need to fill out the program or find it particularly interesting. Confronted with the task of producing a large appendix to...

We describe regression-based methods for analyzing multiple-source data arising from complex sample survey designs in Stata. We use the term multiple-source data to encompass all cases where data are simultaneously obtained from multiple informants, or raters (e.g., self-reports, family members,...

It is fairly simple to add an interaction term (also known as “effect modification” to epidemiologists) to a linear or logistic regression model, and test whether that term is statistically significant. However, it is much more difficult to explain what a significant interaction means in an...