Folks, I'm having trouble with a new installation of R on a macbook pro (OS X). This code used to work on my PC, but now doesn't. I'm wondering what the problem might be. Any help would be much appreciated. -Don Here's what I've been running (and running up against): + male + white, + model = "logit", + data = sd.data) How to cite this model in Zelig: Kosuke Imai, Gary King, and Oliva Lau. 2008. "logit: Logistic Regression for Dichotomous Dependent Variables" in Kosuke Imai, Gary King, and Olivia Lau, "Zelig: Everyone's Statistical Software," http://gking.harvard.edu/zelig Call: zelig(formula = bc.guilty.bin ~ male + white, model = "logit", data = sd.data) Deviance Residuals: Min 1Q Median 3Q Max -1.101 -0.854 -0.803 1.321 1.606 Coefficients: Estimate Std. Error z value Pr(>|z|) (Intercept) -0.331 0.157 -2.11 0.03490 * male 0.148 0.156 0.95 0.34367 white -0.637 0.170 -3.74 0.00018 *** --- Signif. codes: 0 ‘***’ 0.001 ‘**’ 0.01 ‘*’ 0.05 ‘.’ 0.1 ‘ ’ 1 (Dispersion parameter for binomial family taken to be 1) Null deviance: 970.45 on 765 degrees of freedom Residual deviance: 956.24 on 763 degrees of freedom AIC: 962.2 Number of Fisher Scoring iterations: 4 Error in sim(z.out, x = x.out) : unused argument(s) (list(coefficients = c(-0.33055376498435, 0.147796121774405, -0.636859852954591), residuals = c(-1.38006476068037, -1.38006476068037, -1.44060015352681, -1.44060015352681, -1.44060015352681, -1.44060015352681, -1.44060015352681, -1.44060015352681, -1.44060015352681, 3.26963152871244, -1.38006476068037, -1.38006476068037, 2.20052341781859, 3.26963152871244, -1.38006476068037, -1.38006476068037, -1.38006476068037, -1.44060015352681, -1.44060015352681, -1.44060015352681, -1.44060015352681, -1.83297000721323, Error in summary(s.out) : object "s.out" not found