I have a data set of 170K observations with 5 variables and want to match the treated and non-treated observations. So I used the following commands in R:

mat <-  cem(treatment = "treated", data = data, drop = todrop)

psample <- pair(mat, data = data)

The first command runs in couple of seconds. However, the second command runs for a day and then RStudio gets aborted and needs to be restarted.

Any idea how to fix this?

Many thanks,

Meysam 
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