(Internal) Helper function to create an InfinitySparseMatrix from a set of scores, a treatment indicator, and a caliper width.
Source:R/match_on.R
      scoreCaliper.Rd(Internal) Helper function to create an InfinitySparseMatrix from a set of scores, a treatment indicator, and a caliper width.
Value
An InfinitySparseMatrix object, suitable to be
  passed to match_on as an within argument.