Description

This dataset pertains to children and their families in the United States and is intended to illustrate missing data issues. Note that although the original data are longitudinal, this extract is not.

Usage

Format

A data frame with 400 randomly subsampled observations on the following 7 variables.

ppvtr.36

a numeric vector with data on the Peabody Picture Vocabulary Test (Revised) administered at 36 months

first

indicator for whether child was first-born

b.marr

indicator for whether mother was married when child was born

income

a numeric vector with data on family income in year after the child was born

momage

a numeric vector with data on the age of the mother when the child was born

momed

educational status of mother when child was born (1 = less than high school, 2 = high school graduate, 3 = some college, 4 = college graduate)

momrace

race of mother (1 = black, 2 = Hispanic, 3 = white)

Note that momed would typically be an ordered factor while momrace would typically be an unorderd factor but both are numeric in this data.frame in order to illustrate the mechanism to change the type of a missing_variable

Source

National Longitudinal Survey of Youth, 1997, http://www.bls.gov/nls/nlsy97.htm

Examples