My Papers and ProgramsSome of my statistical papers, presentations and computer programs.
Articles and Chapters
Reprints by kind permission of [1] Wolters-Kluwer Publishers, [2] the American Statistical Association, and the [3] the International Biometric Society. Presentations
Web ArticlesThese are mostly online articles and do not include my other articles publications.
An old FAQ on Rasch models and software. Also has information on IRT and latent trait models.
Programs
Latent Trait Analysis and IRT modeling with dichotomous items or manifest variables. This program will estimate both normal-ogive and logistic-ogive IRT models using the marginal maximum likelihood method. Bayesian (expected a posteriori; EAP) scores are calculated for each respondent or response pattern. The program can be used to estimate a one-factor common factor analysis model for dichotomous items. The program is very user friendly. Located Latent Class Analysis---a discrete latent trait model, with latent classes located on a latent trait dimension, as described in Uebersax JS, JASA, 1993. Includes excecutable program, FORTRAN source, User's Guide, and examples. Latent Trait Mixture Analysis, as described in Uebersax JS, Grove WM, Biometrics, 1993. This model can be understood as a mixture of latent traits, or a form of conditional-dependence LCA. A common use is to estimate accuracy of diagnostic tests in the absence of a "gold standard." Includes excecutable program, FORTRAN source, User's Guide, and examples. Very user-friendly program to produce a matrix of tetrachoric correlations. Also supplies standard errors, confidence intervals, p-values, and item thresholds. Provisions for smoothing a potentially improper correlation matrix. POLYCORR 1.1, a program with advanced features to estimate the polychoric correlation coefficient. Calculates the polychoric correlation for a single table, but has many options.
Calculate the tetrachoric correlation coefficient. For a single table. Very easy to use--just enter the four frequencies and get the answer. Also reports standard error, item thresholds, etc. Simple program to test marginal homogeneity in 2-way tables using McNemar and Stuart-Maxwell tests. The Bhapkar test is also performed. An easy-to-use but technically solid program to generate random multivariate-normal data. Simple program to perform conditional dependence diagnostics on a latent class analysis solution. Includes executable code, QuickBASIC source, instructions, and example.
User-friendly program to estimate a mixture of binomials. Includes executable program and short documentation.
Simple utility to calculate the probit function.
Performs unidimensional scaling based on pair-comparison ratings.
Extremely easy to use program for average-linkage hierarchical cluster analysis. Executable code and source code (in both fortran and QuickBasic versions) included. User supplies similiarity/dissimilarity matrix. This version limited to 100 objects, but the limit can be increased. Ideal for cluster analysis of variables/items. Go to Latent Structure Analysis site Go to Rater Agreement site Last updated: 20 Apr 2010 (reprints) (c) 2000-2010 John Uebersax PhD email |