Skip to contents

Between-country population-weighted Gini of per-capita food supply.

Source: R/food_gini.R
calculate_food_gini.Rd

Reduces a per-capita nourishment series to a per-year, between-country, population-weighted Gini coefficient, a diagnostic of how unequally per-capita supply is shared across countries (it does not rescale the per-country nourishment score). Within each year, countries are sorted in descending per-capita supply; each country's population fraction pop_frac and its share of the total supply mass value_frac (per-capita supply times population, over the world total) give a score value_frac * (pop_frac + 2 * richer_frac), where richer_frac is the cumulative population fraction of the strictly richer countries. The Gini is 1 - sum(score) over the countries in that year, 0 under a perfectly equal distribution and rising toward 1 as supply concentrates. Protein per-capita supply is the SJOS-N nourishment axis, so it is the default; passing a different value_col (for example energy_kcal_cap_day) takes the Gini of that axis instead. Rows with a missing supply or population value are dropped before the computation.

Usage

calculate_food_gini(x, value_col = protein_g_cap_day, pop_col = population)

Arguments

x

A tibble with a year column, the per-capita supply column named by value_col and the population column named by pop_col (for example a build_food_supply() output).

value_col

The unquoted per-capita supply column whose between-country inequality is measured. Defaults to protein_g_cap_day.

pop_col

The unquoted population column used as the inequality weight. Defaults to population.

Value

A tibble keyed by year with the gini coefficient.

Examples

calculate_food_gini(
  tibble::tribble(
    ~year, ~area_code, ~protein_g_cap_day, ~population,
    2000L, 10L, 40, 100,
    2000L, 20L, 40, 100,
    2000L, 30L, 40, 100
  )
)
#> # A tibble: 1 × 2
#>    year  gini
#>   <int> <dbl>
#> 1  2000     0