pomp: Recode a Numeric Vector to Percentage of Maximum Possible (POMP) Units

Description

pomp recodes a numeric vector to percentage of maximum possible (POMP) units. This can be useful when data is measured with arbitrary units (e.g., Likert scale).

Usage

pomp(x, mini, maxi, relative = FALSE, unit = 1)

Value

numeric vector from recoding x to percentage of maximum possible (pomp) with units specified by unit.

Arguments

x: numeric vector.
mini: numeric vector of length 1 specifying the minimum numeric value possible.
maxi: numeric vector of length 1 specifying the maximum numeric value possible.
relative: logical vector of length 1 specifying whether relative POMP scores (rather than absolute POMP scores) should be created. If TRUE, then the mini and maxi arguments are ignored. See details for the distinction between absolute and relative POMP scores.
unit: numeric vector of length 1 specifying how many percentage points is desired for the units. Traditionally, POMP scores use unit = 1 (default) such that one unit is one percentage point. However, another option is to use unit = 100 such that one unit is all 100 percentage points (i.e., proportion of maximum possible). This argument also gives the flexibility of specifying units in between 1 and 100 percentage points. For example, unit = 50 would mean that one unit represents going from low (i.e., 25th percentile) to high (i.e., 75th percentile) on the variable.

Details

There are too common approaches to POMP scores: 1) absolute POMP units where the minimum and maximum are the smallest/largest values possible from the measurement instrument (e.g., 1 to 7 on a Likert scale) and 2) relative POMP units where the minimum and maximum are the smallest/largest values observed in the data (e.g., 1.3 to 6.8 on a Likert scale). Both will be correlated perfectly with the original units as they are each linear transformations.

Examples

Run this code

vec <- psych::bfi[[1]]
pomp(x = vec, mini = 1, maxi = 6) # absolute POMP units
pomp(x = vec, relative = TRUE) # relative POMP units
pomp(x = vec, mini = 1, maxi = 6, unit = 100) # unit = 100
pomp(x = vec, mini = 1, maxi = 6, unit = 50) # unit = 50