Hi,
I am using Coursened Exact Matching to improve balance in my sample. The summary matching
results after applying CEM are that 11,128 pixels have been matched:
Sample sizes:
Control Treated
All 19741 8283
Matched 6728 4400
Unmatched 13013 3883
Discarded 0 0
Firstly, is it possible to specify 1:1 matching with CEM? I want to only retain matched
pairs, which requires the same amount of pixels in my treatment & control groups.
I am also having trouble getting a unique identifier for each matched pair so that I can
calculate the difference between the treatment and control. I am using the code:
pair: Produces a paired sample out of a CEM match solution
When I execute the below command, it says there are 0 matches.
# we want a set of paired units
pairsample <- pair(match.out_cem, data)
Total number of units paired in CEM strata: 0
Total number of units matched: 0
Can anyone help or point me in the right direction?
Thanks, Tori
Victoria Graham | MPhil., PhD candidate
Macquarie University NSW 2109 Australia
T: +61 2 9850 6298 | E:
victoria.graham@mq.edu.au<mailto:victoria.graham@mq.edu.au>
Twitter:@ToriFGraham<https://twitter.com/ToriFGraham>
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