make_areal_domain: Create an areal spatial domain for SAR/CAR models

In sdmTMB: Spatial and Spatiotemporal SPDE-Based GLMMs with 'TMB'

Create an areal spatial domain for SAR/CAR models

Description

Build an areal domain object with adjacency weights and unit labels. The returned object can be supplied to mesh in sdmTMB() in areal SAR/CAR workflows.

Usage

make_areal_domain(
  spatial_domain,
  space_column = NULL,
  id_column = NULL,
  adjacency = c("rook", "queen")
)

Arguments

spatial_domain	A named igraph object or an sf/sfc polygon object.
space_column	Column name in model data that identifies areal unit membership. For sf polygon input, defaults to id_column when id_column is supplied; otherwise defaults to "area".
id_column	Optional column name in an sf polygon spatial_domain containing areal unit IDs. If omitted for sf polygons, stable IDs are generated.
adjacency	Polygon adjacency type for sf polygon input: "rook" for shared edges or "queen" for any touching boundary.

Value

A list with class c("sdmTMBareal", "sdmTMBdomain").

Examples

data(ohio_df)
data(ohio_sf)

domain <- make_areal_domain(ohio_sf, id_column = "county")
domain$n_s
domain$unit_names


fit <- sdmTMB(
  cases ~ pct_male,
  data = ohio_df,
  mesh = domain,
  spatial_model = "car",
  family = poisson(link = "log"),
  offset = log(ohio_df$pop)
)

sdmTMB documentation built on July 4, 2026, 1:06 a.m.