Matheron classical semivariogram estimator with its (4.25) variance

Equation (4.24). Provided alongside morie_cressie_hawkins() so the two can be read on identical lag classes; morie_spatial_variogram bins differently and is kept for backwards compatibility.

Usage

morie_matheron_estimator(coords, z, bins = NULL, cutoff = NULL, exact = FALSE)

Arguments

coords: Matrix of coordinates, one row per location.
z: Observed values.
bins: Lag-class count, or explicit bin edges.
cutoff: Largest separation used; half the maximum by default.
exact: Treat every distinct separation as its own lag class.

Value

A list with lag, gamma, n_pairs, variance, sparse_lags.

References

Schabenberger O, Gotway CA (2005), Sec 4.4.1, eq (4.24) and (4.25), pp. 153-158.

Examples

V <- c(1, 2, 3, 4, 5, 6, 7, 8)
morie_matheron_estimator(V, V)
#> $lag
#> [1] 1 2 3
#> 
#> $gamma
#> [1] 0.5 2.0 4.5
#> 
#> $n_pairs
#> [1] 7 6 5
#> 
#> $variance
#> [1] 0.07142857 1.33333333 8.10000000
#> 
#> $sparse_lags
#> [1] 0 1 2
#> 
#> $n
#> [1] 8
#> 
#> $method
#> [1] "Matheron classical semivariogram estimator"
#>