Digit preference test — digitPreference • nipnTK

Digit preference is the observation that the final number in a measurement occurs with a greater frequency that is expected by chance. This can occur because of rounding, the practice of increasing or decreasing the value in a measurement to the nearest whole or half unit, or because data are made up. The digitPreference() function assesses the level by which digit preference exists in a given dataset using a digit preference score (DPS).

Usage

digitPreference(x, digits = 1, values = 0:9)

Arguments

x: Numeric vector of measurements
digits: Number of decimal places in x. Using digits = 1 (e.g.) allows 105 to be treated as 105.0
values: A vector of possible values for the final digit (default = 0:9)

Value

A list of class "digitPreference" with:

Variable	Description
dps	Digit Preference Score (DPS)
tab	Table of final digit counts
pct	Table of proportions (\%) of final digit counts

Details

DPS definition from:

Kari Kuulasmaa K, Hense HW, Tolonen H (for the WHO MONICA Project), Quality Assessment of Data on Blood Pressure in the WHO MONICA Project, WHO MONICA Project e-publications No. 9, WHO, Geneva, May 1998 available from https://www.thl.fi/publications/monica/bp/bpqa.htm

Examples

# Digit preference test applied to anthropometric data from a single state
# from a DHS survey in a West African country
svy <- dp.ex01
digitPreference(svy$wt, digits = 1)
#> 
#> 	Digit Preference Score
#> 
#> data:	svy$wt
#> Digit Preference Score (DPS) = 11.86 (Good)
#>