Hi Bill,

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!

As you guessed, this occurs when weights are applied to a logit model in R. CEM uses weights to correctly estimate treatment effects because multiple controls could be matched to multiple treated units. See Section 2.5 here:

http://gking.harvard.edu/files/political_analysis-2011-iacus-pan_mpr013.pdf

Sorry to say I don't know anything about the error you're seeing.

Hope that helps!

Cheers,

matt.

~~~~~~~~~~~

Matthew Blackwell

Institute for Quantitative Social Science

Department of Government

Harvard University

url: http://www.mattblackwell.org

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:

> run

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:

> summary(run)

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

-
--
cem Mailing List, served by HUIT
Send messages: cem@lists.gking.harvard.edu
[un]subscribe Options: http://lists.gking.harvard.edu/?info=cem
More information on cem: http://gking.harvard.edu/cem
Cem mailing list
Cem@lists.gking.harvard.edu
https://lists.gking.harvard.edu/mailman/listinfo/cem