Find the maximum caliper width that will create a feasible problem.
Source:R/feasible.R
maxCaliper.RdLarger calipers permit more possible matches between treated and control
groups, which can be better for creating matches with larger effective sample
sizes. The downside is that wide calipers may make the matching problem too big
for processor or memory constraints. maxCaliper attempts to find a
caliper value, for a given vector of scores and a treatment indicator, that
will be possible given the maximum problem size constraints imposed by
fullmatch and pairmatch.
Arguments
- scores
A numeric vector of scores providing 1-D position of units
- z
Treatment indicator vector
- widths
A vector of caliper widths to try, will be sorted largest to smallest.
- structure
Optional factor variable that groups the scores, as would be used by
exactMatch. Including structure allows for wider calipers.- exact
A logical indicating if the exact problem size should be computed (
exact = TRUE) or if a more computationally efficient upper bound should be used instead (exact = FALSE). The upper bound may lead to narrower calipers, even if wider calipers would have sufficed using the exact method.