Hi there dear R users!

Anyone knows why does matchit function returns error whenever the "hull" option is used (either "hull.both", "hull.control" or "hull.treat"). Things work well with all the rest of discard options.

This is the error msg.

>m.out.base <- matchit(formula=f, data=d, method=m, discard="hull.control")
[1] "Preprocessing data ..."
[1] "Performing convex hull test ..."
[1] "Calculating distances ...."
[1] "Calculating the geometric variance..."
[1] "Calculating cumulative frequencies ..."
[1] "Finishing up ..."
Error in weights.matrix(match.matrix, treat, discarded) : 
  No units were matched

I hope someone has a clue why this is happening. I'll appreciate your help a lot.

Best regards,

Ana
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