Calculates a degree of spatial association between regionalizations
or categorical maps using the information-theoretical V-measure
(Nowosad and Stepinski (2018)
The sabre (Spatial Association Between
REgionalizations) is an R package for calculating a degree of
spatial association between regionalizations or categorical maps. This
package offers support for sf
spatial objects, and the following
methods:
You can install the released version of sabre
from
CRAN with:
install.packages("sabre")
You can install the development version from GitHub with:
# install.packages("devtools")devtools::install_github("Nowosad/sabre")
We use two simple regionalization, regions1
and regions2
to show the
basic concept of calculating a degree of spatial association.
library(sabre)library(sf)data("regions1")data("regions2")
The first map, regions1
consists of four regions of the same shape and
size, while the second one, regions2
has three irregular
regions.
The vmeasure_calc()
function allows for calculation of a degree of
spatial association between regionalizations or categorical maps using
the information-theoretical V-measure. It requires, at least, four
arguments:
x
- an sf
object containing the first regionalizationx_name
- a name of the column with regions names of the first
regionalizationy
- an sf
object containing the second regionalizationy_name
- a name of the column with regions names of the second
regionalizationregions_vm = vmeasure_calc(regions1, z, regions2, z)
The result is a list with three metrics of spatial association -
V-measure
, Homogeneity
, Completeness
- and two sf
objects with
preprocessed input maps - $map1
and $map2
.
regions_vm#> The SABRE results:#>#> V-measure: 0.36#> Homogeneity: 0.32#> Completeness: 0.42#>#> The spatial objects could be retrived with:#> $map1 - the first map#> $map2 - the second map
Both spatial outputs have two columns. The first one contains regions’
names/values and the second one (rih
) describes regions’
inhomogeneities.
plot(regions_vm$map1["rih"], main = "Map1: rih")plot(regions_vm$map2["rih"], main = "Map2: rih")
More examples can be found in the package vignette and in the sabre: or how to compare two maps? blog post.
Additionally, examples presented in the Spatial association between regionalizations using the information-theoretical V-measure article can be reproduced using data available at http://sil.uc.edu/cms/index.php?id=data-1#vmeasure.