na.roughfix: Rough Imputation of Missing Values
In iRF: iterative Random Forests

Description Usage Arguments Value Note Author(s) See Also Examples

Impute Missing Values by median/mode.

1	na.roughfix(object, ...)

`object`	a data frame or numeric matrix.
`...`	further arguments special methods could require.

A completed data matrix or data frame. For numeric variables, NAs are replaced with column medians. For factor variables, NAs are replaced with the most frequent levels (breaking ties at random). If object contains no NAs, it is returned unaltered.

This is used as a starting point for imputing missing values by random forest.

Andy Liaw

rfImpute, randomForest.

data(iris)
iris.na <- iris
set.seed(111)
## artificially drop some data values.
for (i in 1:4) iris.na[sample(150, sample(20)), i] <- NA
iris.roughfix <- na.roughfix(iris.na)
iris.narf <- randomForest(Species ~ ., iris.na, na.action=na.roughfix)
print(iris.narf)