R/poverty.R

In validmeasures/wsup: An Implementation of the WSUP Urban Water and Sanitation Survey in R

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#
#' Calculate poverty indicators based on the Poverty Probability Index (PPI).
#' 
#' @param surveyData A data frame containing informatiom to be used for
#'     calculating the Poverty Probability Index (PPi)
#' @param index A numeric vector of length equal to \code{surveyData} containing 
#'     data on the calculated PPI score
#' @param ccode Three letter ISO code for a country
#' @param ppiTable Name of country PPI table to use from the ppitables package
#' @return A data frame containing calculated PPI scores, corresponding poverty
#'     probabilities and wealth quintile
#' @examples
#' ppiMatrixBGD <- washdata::ppiMatrixBGD
#' povertyDF <- get_poverty_vars(surveyData = washdata::surveyDataBGD, 
#'                               index = ppi, 
#'                               ccode = "BGD",
#'                               ppiTable = ppitables::ppiBGD2013)
#' 
#' @export
#'
#'
#
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get_poverty_vars <- function(surveyData, index, ccode, ppiTable) {
  ## Calculate PPI score
  ppi <- ppicalc::score_ppi_cohort(data = surveyData, ccode = ccode)
  ## Determine poverty probabilities
  povertyDF <- ppicalc::get_ppi_cohort(index = ppi, ppiTable = ppiTable)
  ## Get quintile cut-offs
  qCutOff <- quantile(ppi, probs = c(0.2, 0.4, 0.6, 0.8, 1))
  ## Classify households by wealth quintile
  pQuintile <- ifelse(ppi <= qCutOff[1], 1,
                 ifelse(ppi > qCutOff[1] & ppi <= qCutOff[2], 2,
                   ifelse(ppi > qCutOff[2] & ppi <= qCutOff[3], 3,
                     ifelse(ppi > qCutOff[3] & ppi <= qCutOff[4], 4, 5))))
  ## Create povertyDF
  povertyDF <- data.frame("uniqueID" = surveyData[ , "uniqueID"], ppi, 
                          pQuintile, povertyDF)
  ## Return output
  return(povertyDF)
}