Try creating larger strata.
Kosuke Imai
Professor, Department of Politics
Center for Statistics and Machine Learning
Princeton University
On Mon, May 15, 2017 at 12:30 PM, Guogen Shan <guogen.shan(a)unlv.edu> wrote:
Dear Prof. Imai, Thanks for your prompt response.
This strata approach
works great when the control group has at least one subject having the same
age as one subject from the treatment group. The control group in our study
is not large enough to meet that assumption. Any comments? Thank you.
Guogen
On May 15, 2017 6:52 AM, "Kosuke Imai" <kimai(a)princeton.edu> wrote:
> You can stratify the age variable and then do a matching with an extract
> restriction on that strata.
>
> Kosuke Imai
> Professor, Department of Politics
> Center for Statistics and Machine Learning
> Princeton University
>
http://imai.princeton.edu
>
> On Sun, May 14, 2017 at 11:58 PM, Guogen Shan <guogen.shan(a)unlv.edu>
> wrote:
>
>> Dear Prof. Imai,
>>
>> Thanks for developing the MatchIt package. I have a data set from a
>> treatment, and I want to match it with another data base (control), by age,
>> race, education. Age is the primary match criteria, followed by race, and
>> education. In other words, I want to give more weights to the age
>> difference than those to race difference. Any suggestion how to use your
>> package for this type of matching?
>>
>> Thank you.
>>
>> Guogen
>>
>
>