Dispersion as pooled across a treatment and a control group. By default,
the measure of dispersion calculated within each group is not the
ordinary standard deviation as in stats::sd
but rather the robust alternative
encoded in stats::mad
. The dispersion measurements are combined
by squaring, averaging with weights proportional to one minus the sizes of
the groups and then taking square roots. Used in match_on.glm
.
standardization_scale(x, trtgrp, standardizer = NULL, svydesign_ = NULL)
numeric of length 1
numeric variable
logical or numeric. If numeric, coerced to logical via !
function, NULL
or numeric of length 1
ordinarily NULL
, but may also be a
survey.design2
; see Details.
A non-NULL svydesign_
parameter indicates that the dispersion
calculations are to be made respecting the weighting scheme implicit in
that survey.design2
object. If standardizer
is NULL
,
one gets a calculation in the style of stats::mad
but with weights,
performed by optmatch:::svy_sd
; for a pooling of weighted standard
deviations, one would pass a non-NULL
svydesign_
parameter along
with standardizer=optmatch:::svy_sd
.
(More generally, the provided standardizer
function should accept as a sole argument a survey.design2
object,
with nrows(svydesign_$variables)
equal to the lengths of x
and
trtgrp
. This object is expected to carry a numeric variable ‘x
’,
and the standardizer
function is to return the dispersion of this variable.)