mice (version 1.14)

mids: Multiply Imputed Data Set

Description

An object containing a multiply imputed data set. The "mids" object is generated by the mice and mice.mids functions. The "mids" class of objects has methods for the following generic functions: print, summary, plot

Usage

## S3 method for class 'mids':
print(x, \dots)
## S3 method for class 'mids':
summary(object, \dots)
## S3 method for class 'mids':
plot(x, y, \dots)

Arguments

x
A mids object.
object
A mids object.
y
Not used.
...
Not used.

Value

  • callThe call that created the object.
  • dataA copy of the incomplete data set.
  • mThe number of imputations.
  • nmisAn array containing the number of missing observations per column.
  • impA list of nvar components with the generated multiple imputations. Each part of the list is a nmis[j] by m matrix of imputed values for variable j.
  • imputationMethodA vector of strings of length(nvar) specifying the elementary imputation method per column.
  • predictorMatrixA square matrix of size ncol(data) containing 0/1 data specifying the predictor set.
  • visitSequenceThe sequence in which columns are visited.
  • seedThe seed value of the solution.
  • iterationLast Gibbs sampling iteration number.
  • lastSeedValueThe most recent seed value.
  • chainMeanA list of m components. Each component is a length(visitSequence) by maxit matrix containing the mean of the generated multiple imputations. The array can be used for monitoring convergence. Note that observed data are not present in this mean.
  • chainCovA list with similar structure of itermean, containing the covariances of the imputed values.
  • padA list containing various settings of the padded imputation model, i.e. the imputation model after creating dummy variables. Normally, this array is only useful for error checking.

References

Van Buuren, S. & Oudshoorn, C.G.M. (2000). Multivariate Imputation by Chained Equations: MICE V1.0 User's manual. Report PG/VGZ/00.038, TNO Prevention and Health, Leiden.