Imputes univariate missing data using linear discriminant analysis
Arguments
- y
Vector to be imputed
- ry
Logical vector of length
length(y)
indicating the the subsety[ry]
of elements iny
to which the imputation model is fitted. Thery
generally distinguishes the observed (TRUE
) and missing values (FALSE
) iny
.- x
Numeric design matrix with
length(y)
rows with predictors fory
. Matrixx
may have no missing values.- wy
Logical vector of length
length(y)
. ATRUE
value indicates locations iny
for which imputations are created.- ...
Other named arguments. Not used.
Details
Imputation of categorical response variables by linear discriminant analysis.
This function uses the Venables/Ripley functions lda()
and
predict.lda()
to compute posterior probabilities for each incomplete
case, and draws the imputations from this posterior.
This function can be called from within the Gibbs sampler by specifying
"lda"
in the method
argument of mice()
. This method is usually
faster and uses fewer resources than calling the function, but the statistical
properties may not be as good (Brand, 1999).
mice.impute.polyreg
.
Warning
The function does not incorporate the variability of the
discriminant weight, so it is not 'proper' in the sense of Rubin. For small
samples and rare categories in the y
, variability of the imputed data
could therefore be underestimated.
Added: SvB June 2009 Tried to include bootstrap, but disabled since bootstrapping may easily lead to constant variables within groups.
References
Van Buuren, S., Groothuis-Oudshoorn, K. (2011). mice
:
Multivariate Imputation by Chained Equations in R
. Journal of
Statistical Software, 45(3), 1-67.
doi:10.18637/jss.v045.i03
Brand, J.P.L. (1999). Development, Implementation and Evaluation of Multiple Imputation Strategies for the Statistical Analysis of Incomplete Data Sets. Ph.D. Thesis, TNO Prevention and Health/Erasmus University Rotterdam. ISBN 90-74479-08-1.
Venables, W.N. & Ripley, B.D. (1997). Modern applied statistics with S-PLUS (2nd ed). Springer, Berlin.
See also
mice
, link{mice.impute.polyreg}
,
lda
Other univariate imputation functions:
mice.impute.cart()
,
mice.impute.lasso.logreg()
,
mice.impute.lasso.norm()
,
mice.impute.lasso.select.logreg()
,
mice.impute.lasso.select.norm()
,
mice.impute.logreg()
,
mice.impute.logreg.boot()
,
mice.impute.mean()
,
mice.impute.midastouch()
,
mice.impute.mnar.logreg()
,
mice.impute.mpmm()
,
mice.impute.norm()
,
mice.impute.norm.boot()
,
mice.impute.norm.nob()
,
mice.impute.norm.predict()
,
mice.impute.pmm()
,
mice.impute.polr()
,
mice.impute.polyreg()
,
mice.impute.quadratic()
,
mice.impute.rf()
,
mice.impute.ri()