questionr (version 0.2)

freq.na: Generate frequency table of missing values.

Description

Generate a frequency table of missing values as raw counts and percentages.

Usage

freq.na(data, ...)

Arguments

data

either a vector or a data frame object

...

if x is a data frame, the names of the variables to examine. When no variable names are provided, the function examines the full data frame and returns the five variables with most missing values.

Value

• The result is an object of class data.frame.

See Also

table, is.na

Examples

data(hdv2003)
## Examine a single vector.
freq.na(hdv2003$qualif)
## Examine a data frame.
freq.na(hdv2003)
## Examine several variables.
freq.na(hdv2003, "nivetud", "trav.satisf")
## Examine all variables.
freq.na(hdv2003, names(hdv2003))