Generate a random spatial weight matrix.

Description

Generate a spatial weight matrix of given size and number of nearest neighbors from randomly-located observations on the unit square.

Usage

1
generate_W(n, nneigh, seed=123)

Arguments

n

the size of the matrix.

nneigh

the number of nearest neighbors.

seed

an integer to set the seed for the random generated locations.

Details

The output matrix has zero diagonal and it is row-standardised. The n observations are allocated randomly in the unit square. For each observation, the nneigh closests observations w.r.t. the Euclidean distance are assigned with a weight equal to 1/nneigh.

Value

a matrix of class dgCMatrix (sparse matrix).

See Also

sim_binomial_probit.

Examples

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W <- generate_W(100,4,seed=12)
image(W)