Hi, I asked this question about six weeks ago, but had not heard anything back. Any help would be greatly appreciated. Thanks, Bill ---------- Forwarded message ---------- From: William Mabe <billmabe(a)gmail.com> Date: Wed, Apr 25, 2012 at 10:01 PM Subject: cem and multiply imputed data sets from Amelia To: cem(a)lists.gking.harvard.edu I am using cem to match treatment and control group members from 5 multiply imputed datasets from Amelia. I've encountered two types of problems. First, when I run a logit model after calling cem on the multiply imputed datasets: LOG_CA_SCORE + LOG_CM_SCORE, data = imputed, model = "logit") I get the following warning messages, one for each multiply imputed dataset: Warning messages: 1: In eval(expr, envir, enclos) : non-integer #successes in a binomial glm! 2: In eval(expr, envir, enclos) : non-integer #successes in a binomial glm! 3: In eval(expr, envir, enclos) : non-integer #successes in a binomial glm! 4: In eval(expr, envir, enclos) : non-integer #successes in a binomial glm! 5: In eval(expr, envir, enclos) : non-integer #successes in a binomial glm! My dependent variable had no missing cases, so the values for it were not imputed for any observations, and I have checked that the values of it are either 0 or 1. Any ideas why I am getting this warning? I've noticed from searching online that this warning arises when weights are included in a binomial glm model, so I wonder if it might have something to do with how cem is weighting the control observations. (2) The second issue relates to displaying the output of the model. When I type: I get: Logistic model on CEM matched data: SATT point estimate: 1.509872 (p.value=0.001640) 95% conf. interval: [0.570028, 2.449717] which is fine, but when I type: I get: Treatment effect estimation for data: NULL Logistic model estimated on matched data only Coefficients: Error in symnum(pv, corr = FALSE, na = FALSE, cutpoints = c(0, 0.001, : 'x' must be between 0 and 1 Any idea why I'm getting this error? Thanks for any help you can provide, Bill

this is not an error but a warning and it means that you are trying to fit a logit model with non binary variables as response or that the binary variable is essentially constant or the weights issue. It is impossible to say more without an example for replication but again, this is only a warning of glm sorry cannot say more without data and script bests stefano Sent from my StrawBerry® On 07/giu/2012, at 20:09, Matt Blackwell <blackwel(a)fas.harvard.edu> wrote: