Soil Chemistry Properties Data

Source: R/mcglm.R

Soil chemistry properties measured on a regular grid with 10 x 25 points spaced by 5 meters.

  • COORD.X - X coordinate.

  • COORD.Y - Y coordinate.

  • SAND - Sand portion of the sample.

  • SILT - Silt portion of the sample.

  • CLAY - Clay portion of the sample.

  • PHWATER - Soil pH at water.

  • CA - Calcium content.

  • MG - Magnesium content.

  • K - Potassio content.

data(soil)

Format

a data.frame with 250 records and 9 variables.

Source

Bonat, W. H. (2018). Multiple Response Variables Regression Models in R: The mcglm Package. Journal of Statistical Software, 84(4):1--30.

Examples

data(soil, package="mcglm")
## neigh <- spdep::tri2nb(soil[,1:2])
## Spatial model
## Z1 <- mc_car(neigh) take too long
Z1 <- mc_id(soil)
# Linear predictor
form.ca <- CA ~ COORD.X*COORD.Y + SAND + SILT + CLAY + PHWATER
fit.ca <- mcglm(linear_pred = c(form.ca), matrix_pred = list(Z1),
               link = "log", variance = "tweedie", covariance = "inverse",
               power_fixed = TRUE, data = soil,
               control_algorith = list(max_iter = 1000, tuning = 0.1,
               verbose = FALSE, tol = 1e-03))
#> Automatic initial values selected. 
## mc_compute_rho(fit.ca) only for spatial model