na.omit, but adds frequency of missing values
for each predictor
to the
"na.action" attribute of the returned model frame.
Optionally stores further details if
options(na.detail.response=TRUE).
na.delete(frame)
"na.action" attribute added.
Frank Harrell
Department of Biostatistics
Vanderbilt University
f.harrell@vanderbilt.edu
# options(na.action="na.delete") # ols(y ~ x)