Dear All: I am using R with Zelig and Amelia to do logistic regression for a dataset (finished Multiple Imputation using Amelia). After experimenting with my own dataset, I have a bunch of questions as below. I have provided an executable example FYI. * How do I ask zelig to report, combine the results of odds ratio and its std. error under five datasets ? * How do I plug weight variable into Zelig function? * How can extract the peusudo R-square for models, i.e., z.outft1 and z.out.ft2 ? * Under SPSS, there is a step method to run regression models. It will show the R square(and adjusted Rsquare) change and the significance of adding additional covariates in subsequent models. Or like Stata, I can use chow test to test whether second model bring statistically significant explanatory power. Does R or Zelig package has such function? I know not many people care about R square, but our professor requires us to report the number in the final table. Thank you! Best, Li Chang Below is the example: library(Zelig) library(Hmisc) library(Amelia) data(freetrade) attach(freetrade) tariff[freetrade$tariff < 31.65] <- 1; tariff[freetrade$tariff >= 31.65] <- 0 a.out.freetrade <- amelia(freetrade, m = 5, ts = "year", cs = "country", noms="tariff") ## I want to know odds ratio and std.error , pseudo R square( it will be great if you can also tell me how to extract regular R-square and Adjusted R-square without manual calculation) z.out.ft1 <- zelig(tariff ~ polity + pop + gdp.pc, data = freetrade, model = "logit") summary(z.out.ft1) ## and then under model 2, I want to know the r-square change by adding "year" and "country" z.out.ft2 <- zelig(tariff ~ polity + pop + gdp.pc + year + country, data = freetrade, model = "logit") summary(z.out.ft2)