lowerBound {RankAggregator}

Lower bound value

Description

This function is called by RankAggregator::consensusRanking. The lower bound is the absolute lowest value a complete candidate ranking could attain. Note, this value is not always achievable, so may differ from the value returned by upperBound.

     For each pair of \code{Item}s, there are three possible calculations, depending
     on whether both \code{Item}s are in the \code{partial.ranking}, one is in
     and the other is out the \code{partial.ranking}, or both are not in
     the \code{partial.ranking}.

Usage

lowerBound(umat, partial.ranking)

Arguments

umat

a matrix, which is either the output of evaluationMatrix, or a subset of the output of evaluationMatrix.

partial.ranking

a vector of rank positions for each Item in umat that is ranked so far; partial rankings may contain some - or all - NA values.

Value

A numeric value for the lower bound of a partial.ranking