sar {brms} | R Documentation |
Set up an spatial simultaneous autoregressive (SAR) term in brms. The function does not evaluate its arguments – it exists purely to help set up a model with SAR terms.
sar(M, type = "lag")
M |
An object specifying the spatial weighting matrix.
Can be either the spatial weight matrix itself or an
object of class |
type |
Type of the SAR structure. Either |
The lagsar
structure implements SAR of the response values:
y = ρ W y + η + e
The errorsar
structure implements SAR of the residuals:
y = η + u, u = ρ W u + e
In the above equations, η is the predictor term and e are
independent normally or t-distributed residuals. Currently, only families
gaussian
and student
support SAR structures.
An object of class 'sar_term'
, which is a list
of arguments to be interpreted by the formula
parsing functions of brms.
## Not run: data(oldcol, package = "spdep") fit1 <- brm(CRIME ~ INC + HOVAL + sar(COL.nb, type = "lag"), data = COL.OLD, data2 = list(COL.nb = COL.nb), chains = 2, cores = 2) summary(fit1) plot(fit1) fit2 <- brm(CRIME ~ INC + HOVAL + sar(COL.nb, type = "error"), data = COL.OLD, data2 = list(COL.nb = COL.nb), chains = 2, cores = 2) summary(fit2) plot(fit2) ## End(Not run)