TAF Support

Member Training: Frailty Models

November 2nd, 2023 by

Most survival analysis models for time-to-event data, like Cox regression, assume independence. The survival time for one individual cannot influence the survival time for another.

This assumption doesn’t hold in many study designs. You may have animals clustered into litters, matched pairs, or patients in a multi-center trial with correlated survival times within a center.


Member Training: Operationalizing Research Questions

July 31st, 2023 by

One of the hardest steps in any project is learning to ask the right research question!

Member Training: Interactions in Poisson and Logistic Regression

May 1st, 2023 by

Interactions in statistical models are never especially easy to interpret. Throw in non-normal outcome variables and non-linear prediction functions and they become even more difficult to understand. (more…)

Member Training: Using Macros, Loops, and Functions in Stata to Manage Your Data Software Tutorial

March 31st, 2023 by

Many data sets are challenging and time consuming to work with because the data are seldom in an optimal format.


Member Training: Moderated Mediation, Not Mediated Moderation

February 28th, 2023 by

Moderated mediation, also known as Conditional Process Modeling, is great tool for understanding one type of complex relationship among variables.


Member Training: The Link Between ANOVA and Regression

January 31st, 2023 by

Stage 2If you’ve used much analysis of variance (ANOVA), you’ve probably heard that ANOVA is a special case of linear regression. Unless you’ve seen why, though, that may not make a lot of sense. After all, ANOVA compares means between categories, while regression predicts outcomes with numeric variables.ANOVA chart (more…)