Ordinary co-kriging — morie

Z1*(s0) = sum lambda_i Z1(s_i) + sum mu_j Z2(s_j), solved under the constraints sum lambda = 1 and sum mu = 0. The covariate contributes only through the cross-variogram: set it to zero and the mu weights vanish, leaving ordinary kriging on Z1.

Usage

morie_cokrig(coords, z1, z2, s0, cross_vario = NULL, model = NULL)

Arguments

coords: n x d matrix of coordinates
z1: primary variable
z2: secondary variable
s0: prediction location
cross_vario: cross-variogram function of distance
model: direct variogram function of distance

Value

list with prediction, variance, lambda and mu

Examples

morie_cokrig(coords = c(1, 2, 3, 4, 5, 6, 7, 8), z1 = c(1, 2, 3, 4, 5, 6, 7, 8),
  z2 = c(1, 2, 3, 4, 5, 6, 7, 8), s0 = c(1, 2, 3, 4, 5, 6, 7, 8))
#> $prediction
#> [1] 4.5
#> 
#> $variance
#> [1] 1.362849
#> 
#> $lambda
#> [1] 0.22355078 0.05639900 0.08279913 0.13725109 0.13725109 0.08279913 0.05639900
#> [8] 0.22355078
#> 
#> $mu
#> [1]  7.911723e-17 -5.572161e-18  2.083041e-16 -6.481594e-16  4.367447e-17
#> [6]  8.968107e-16 -7.280427e-16  2.001894e-16
#> 
#> $n
#> [1] 8
#> 
#> $range
#> [1] 3
#>