rimu (version 0.6)

ms_flatten: Flatten a scored multiple-response object into a factor

Description

Convert a multiple-response object into a named numeric vector using a supplied ordering.

Usage

ms_flatten(x, priorities, fun, start=0)

Value

A factor

Arguments

x

mr object

priorities

Character vector of levels.

fun

Function for reducing two values to one.

start

starting value for fun

Details

Each observation is initially assigned the value start. Starting with the lowest-priority level, the current value is combined with the new value as fun(new, current). Using fun=function(x,y) x would return the value for the highest-priority level present; using fun=pmax would return the highest score for any level present; using fun="+" would return the sum of the scores.

Examples

data(ethnicity)
ethnicity

## NZ 'prioritised ethnicity'
eth <- mr_recode(ethnicity, `European/Other`="European", `European/Other` = "MELAA")
mr_flatten(ethnicity, c("Maori","Pacific","Asian","European/Other"))

data(nzbirds)
## hardest to see first
ms_flatten(nzbirds, c("kaki","ruru","kea","tui","tauhou"),"+")
ms_flatten(nzbirds, c("kaki","ruru","kea","tui","tauhou"),
  fun=function(x,y) x)
ms_flatten(nzbirds, c("kaki","ruru","kea","tui","tauhou"),pmin,start=Inf)