Full matching is a subclassification procedure and so you should look at a$subclass
Kosuke
Department of Politics
Princeton University
Hi Kosuke,
When I try to use fullmatching like so:
a <- matchit(glmForm, nData, method =
"full", min.controls = 1, max.controls = 5)
And then try to look at the matches like so:
a$match.matrix
I get a response of NULL, indicating that the object doesn't exist. However when I
use method = "nearest" or method = "optimal" it works just fine. How
can I see the matches that are produced using full-matching?
Thanks,
Skye
-----Original Message-----
From: Kosuke Imai [mailto:kimai@Princeton.EDU]
Sent: Wednesday, November 07, 2012 7:13 PM
To: Buckner-Petty, Skye
Cc: <matchit(a)lists.gking.harvard.edu>
Subject: Re: R MatchIt package
Yes, the variable has to be 0-1 I think.
Kosuke
Department of Politics
Princeton University
http://imai.princeton.edu
On Nov 7, 2012, at 1:53 PM, "Buckner-Petty, Skye"
<SBUCKNER(a)dom.wustl.edu> wrote:
Hi Kosuke,
I am doing some analysis that requires matching and recently come across your package.
However, when trying to run the following code, I get an error:
bbb= matchit(formula = compLbl ~ Age + Race_Code
+ Complexity_Subclass_Code, data = nData, method = "nearest")
Error in
weights.matrix(match.matrix, treat, discarded) :
No units were matched
In addition: Warning messages:
1: In max(pscore[treat == 0]) :
no non-missing arguments to max; returning -Inf
2: In max(pscore[treat == 1]) :
no non-missing arguments to max; returning -Inf
3: In min(pscore[treat == 0]) :
no non-missing arguments to min; returning Inf
4: In min(pscore[treat == 1]) :
no non-missing arguments to min; returning Inf
The variable "compLbl" is dichotomous (group A and group B), but it is not
binary coded (1s and 0s). Does the treatment variable need to be binary coded in order
for it to work?
Thanks,
Skye Buckner-Petty
Statistical Data Analyst
GMS
Department of Medicine
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