mice (version 2.2)

cbind.mids: Columnwise combination of a mids object.

Description

This function combines two mids objects columnwise into a single object of class mids, or combines a mids object with a vector, matrix, factor or data.frame columnwise into an object of class mids. The number of rows in the (incomplete) data x$data and y (or y$data if y is a mids object) should be equal. If y is a mids object then the number of imputations in x and y should be equal. Note: If y is a vector or factor its original name is lost and it will be denoted with y in the mids object.

Usage

cbind.mids(x, y, ...)

Arguments

x

A mids object.

y

A mids object or a data.frame, matrix, factor or vector.

...

Additional data.frame, matrix, vector or factor. These can be given as named arguments.

Value

• An S3 object of class mids

See Also

rbind.mids, ibind, mids

Examples

# append 'forgotten' variable bmi to imp
temp <- boys[,c(1:3,5:9)]
imp  <- mice(temp,maxit=1,m=2)
imp2 <- cbind.mids(imp, data.frame(bmi=boys$bmi))

# append maturation score to imp (numerical)
mat  <- (as.integer(temp$gen) + as.integer(temp$phb)
+ as.integer(cut(temp$tv,breaks=c(0,3,6,10,15,20,25))))
imp2 <- cbind.mids(imp, as.data.frame(mat))

# append maturation score to imp (factor)
# known issue: new column name is 'y', not 'mat'
mat  <- as.factor(mat)
imp2 <- cbind.mids(imp, mat)

# append data frame with two columns to imp
temp2 <- data.frame(bmi=boys$bmi,mat=as.factor(mat))
imp2  <- cbind.mids(imp, temp2)

# combine two mids objects
impa <- mice(temp, maxit=1, m=2)
impb <- mice(temp2, maxit=2, m=2)

# first a then b
impab <- cbind.mids(impa, impb)

# first b then a
impba <- cbind.mids(impb, impa)