Compute Standardized Getis-Ord G*i

Returns standardized local Getis-Ord G*i scores using either an sf object, a zero-indexed adjacency list, or a spatial weights matrix.

gstar_i(shp, adj, wts, spatial_mat, epsg = 3857)

Arguments

shp

sf dataframe. Optional if adj or spatial_mat is supplied.

adj

Zero-indexed adjacency list. Optional if shp or spatial_mat is supplied.

wts

Numeric vector of observed values.

spatial_mat

Square spatial weights matrix. Optional if shp or adj is supplied.

epsg

numeric EPSG code to planarize to. Default is 3857.

Value

numeric vector of standardized G*i scores, one per observation

Examples

library(dplyr)
data('checkerboard')
checkerboard <- checkerboard |> mutate(m = as.numeric((id + i) %% 2 == 0))
gstar_i(shp = checkerboard, wts = checkerboard$m)
#> Warning: Planarizing skipped. `x` missing CRS.
#>  [1]  1.425573 -1.760216  1.760216 -1.760216  1.760216 -1.760216  1.760216
#>  [8] -1.425573 -1.760216  2.049390 -2.049390  2.049390 -2.049390  2.049390
#> [15] -2.049390  1.760216  1.760216 -2.049390  2.049390 -2.049390  2.049390
#> [22] -2.049390  2.049390 -1.760216 -1.760216  2.049390 -2.049390  2.049390
#> [29] -2.049390  2.049390 -2.049390  1.760216  1.760216 -2.049390  2.049390
#> [36] -2.049390  2.049390 -2.049390  2.049390 -1.760216 -1.760216  2.049390
#> [43] -2.049390  2.049390 -2.049390  2.049390 -2.049390  1.760216  1.760216
#> [50] -2.049390  2.049390 -2.049390  2.049390 -2.049390  2.049390 -1.760216
#> [57] -1.425573  1.760216 -1.760216  1.760216 -1.760216  1.760216 -1.760216
#> [64]  1.425573