In a linear model with no interactions, one can speak of "the"
difference in mean Y given X across treatments, independent of X.
In a nonparametric analysis, there is interaction by definition,
and one can only speak of differences across treatments for a
specific X value. Hence the need for the argument
sComparisonPts
.
The specified qeML
function will be called on the indicated data once
for each level of the sensitive variable. For each such level, estimated
regression function values will be obtained for each row in
sComparisonPts
.