MissMech (version 1.0.4)

DelLessData: Removes groups with identical missing data patterns having at most a given number of cases

Description

Removes groups of missing data patterns with number of cases less than or equal to a specified value (ncases).

Usage

DelLessData(data, ncases = 0)

Value

data

A matrix of reaaranged data, according to missing data patterns, with missing data patterns having less than ncases number of cases removed.

patused

A matrix indicating the missing data patterns in the data set; observed variable(s) are indiated by 1's' and missing variables are indicated by NA's.

patcnt

A vector consisting of the number of cases corresponding to each pattern in patused.

spatcnt

Cumulative sum of elements of patcnt.

g

Number of missing data patterns.

caseorder

A mapping of case number indices from output data (rearranged data) to input data.

removedcases

The index of cases that were removed from the original data set

Arguments

data

A matrix consisting of at least two columns. Values must be numerical with missing data indicated by NA.

ncases

Missing data pattern groups with ncases number of cases or less will be removed from the data set.

Author

Mortaza Jamshidian, Siavash Jalal, and Camden Jansen

Examples

set.seed <- 50
n <- 200
p <- 4
pctmiss <- 0.2
y <- matrix(rnorm(n * p),nrow = n)
missing <- matrix(runif(n * p), nrow = n) < pctmiss
y[missing] <- NA
out <- DelLessData(data=y, ncases = 4)
dim(y)
dim(out$data)