Major site update (October 2001)
New LCA software!
Drs. Jeroen Vermunt and Jay Magidson have released their Latent GOLD software for latent class analysis. The program is superb! A technical breakthrough on several fronts. Visit the Statistical Innovations web site for details. (Summer 2000)
New online articles!
Anyone using latent class models should understand the two potential problems of local maximum solutions and local dependence of manifest variables:
I have a new site, the Latent Trait Analysis web pages. It has information on latent trait models, item response theory (IRT) models, and methods for factor analysis of binary data. There's also a separate page that discusses the Tetrachoric and Polychoric Correlation Coefficients . (June 2000)
The Statistical Methods for Rater Agreement web site is now up and running. Information on raw agreement indices, kappa statistics, odds ratio measures, latent class and latent trait models, tetrachoric and polychoric correlations, and other methods for analyzing rater and diagnostic agreement data. (May 2000)
New page, Estimating a Latent Trait Model by Factor Analysis of Tetrachoric Correlations . It explains the method and shows how to apply it with LISREL or SAS. (May 2000)
The paper, "Probit Latent Class Analysis," is now in print (December 1999 issue of Applied Psychological Measurement).
Here is an open letter
Latent Class Analysis and Psychiatric Research
by me and William Grove. It critiques
a series of articles that have used Latent Class Analysis to identify subtypes
of psychiatric disorders. These studies have been good overall, but have
had certain, recurring methodological problems. We wish to encourage
researchers to address these problems in future studies. (March 1999)
Go to Statistical Methods for Rater Agreement
Go to My papers and programs
18 Sep 2009 (Modeling agreement reprint)
14 Oct 2009 (added counter; new references)
22 Mar 2010 (added reprints)
15 Apr 2010 (new page)
John Uebersax Enterprises LLC
(c) 2000-2010 John Uebersax PhD email