path analysis
This solves part of my problem with the independent ordinal variables, but my dependent variable is truly categorial (illness/no illness). Polychoric correlation implies that data are continuous, which in not the case. Is possible to implement logistic regression in the path model? Thanks, Manel Salamero ---------- Original Message ---------------------------------- De: "John Fox" <jfox at mcmaster.ca> Data: Sat, 13 Aug 2005 19:35:24 -0400 Dear Manel,
-----Original Message----- From: r-help-bounces at stat.math.ethz.ch [mailto:r-help-bounces at stat.math.ethz.ch] On Behalf Of SALAMERO BARO, MANUEL Sent: Saturday, August 13, 2005 2:02 PM To: r-help at stat.math.ethz.ch Subject: [R] path analysis Someone knows if it is possible to perform a path analysis with sem package (or any other) to explain a dependent *dichotomus* variable?
Yes -- you can use the hetcor() function in the polycor package to generate a correlation matrix and boot.sem() in the sem package to get standard errors or confidence intervals. Make sure that the dichotomous variables are represented as factors. See ?boot.sem for an example. I hope this helps, John