I have put the new package bindata to CRAN, which provides a method for creating binary (i.e., 0-1-valued) random variables with correlation structures by converting multivariate random variables to binary variables. The package includes a postscript file of a technical report describing the method, here's the abstract: ********************************************************** The generation of random variates from multivariate binary distributions has not gained as much interest in the literature as, e.g., multivariate normal or Poisson distributions. Binary variables are important in many types of applications. Our main interest is in the segmentation of marketing data, where data come from customer questionnaires with ``yes/no'' questions. Artificial data provide a valuable tool for the analysis of segmentation tools, because data with known structure can be constructed to mimic situations from the real world (Dolnicar et al. 1998). Questionnaire data can be highly correlated, when several questions covering the same field are likely to be answered similarly by a subject. In this paper we present a computationally fast method to simulate multivariate binary distributions with a given correlation structure. The implementation of the algorithm in R, an implementation of the S statistical language, is described in the appendix. ********************************************************** -- ------------------------------------------------------------------- Friedrich Leisch Institut f?r Statistik Tel: (+43 1) 58801 4546 Technische Universit?t Wien Fax: (+43 1) 504 14 98 Wiedner Hauptstra?e 8-10/1071 Friedrich.Leisch at ci.tuwien.ac.at A-1040 Wien, Austria http://www.ci.tuwien.ac.at/~leisch PGP public key http://www.ci.tuwien.ac.at/~leisch/pgp.key ------------------------------------------------------------------- -.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.- r-help mailing list -- Read http://www.ci.tuwien.ac.at/~hornik/R/R-FAQ.html Send "info", "help", or "[un]subscribe" (in the "body", not the subject !) To: r-help-request at stat.math.ethz.ch _._._._._._._._._._._._._._._._._._._._._._._._._._._._._._._._._._._._._._._._