A review of issues and controversy surrounding F-ratio denominator degrees of freedom (DDF) in linear mixed models. The presentation will look at the history of denominator degrees of freedom as well survey their use in various statistical packages.

As the title implies, EFA within a CFA framework combines aspects of both EFA and CFA. It uses CFA to produce a factor solution that is close to an EFA solution while providing features typically found in CFA, such as, standard errors, statistical tests and modification indices. The presentation...

Profile analysis is a multivariate method for examining differences in the shapes of profiles across groups. Profile analysis uses of Stata's -manova- command along with -manovatest- for estimation. This presentation will also demonstrate the use of the user written program -profileplot- to...

This presentation will show how to use of the new margins command, introduced in Stata 11, to explore interactions in regression and analysis of variance. The talk will cover three types of interactions: 1) categorical by categorical, 2) categorical by continuous, and 3) continuous by...

Stata's xi command performs dummy (indicator) coding on the fly and with the "*" operator allows for the interaction of two categorical variables or a categorical with a continuous variable. xi3 extends the capabilities of xi to include a number of additional coding systems and can create...

This presentation will give an overview of the three main approaches to analyzing repeated measures analysis of variance: 1) Multivariate models, 2) traditional anova models, and 3) linear mixed models along with discussion of the advantages and disadvantages of each. The presentation includes...

Three approaches to understanding 3-way anova interactions will be presented: 1) a conceptual approach, 2) an anova approach and 3) a regression approach using dummy coding. The three approaches are illustrated through the use of a synthetic dataset with a significant 3-way interaction.

This presentation will cover a collection of statistics teaching tools written in Stata. These programs involve demonstrations or simulations of various statistical topics that are used both in the classroom and individually by the students. Topics include probability (coin, dice, box models),...

The aim of this research project is to see how intra-social group mobility affected mortality patterns in Sweden; the project covers the transition from a preindustrial to an industrial society. According to previous studies (see Bengtsson 2010; Bengtsson and Van Poppel 2011; Bengtsson and Dribe 2011;...

The classical stochastic frontier panel-data models provide no mechanism to disentangle individual time-invariant unobserved heterogeneity from inefficiency. Greene (2005a,b) proposed the so-called true fixed-effects specification that distinguishes these two latent components and allows for...