# NOT RUN {
# Acquire environmental variables
files <- list.files(path = file.path(system.file(package = "dismo"), "ex"),
pattern = "grd", full.names = TRUE)
predictors <- raster::stack(files)
# Prepare presence locations
p_coords <- condor[, 1:2]
# Prepare background locations
bg_coords <- dismo::randomPoints(predictors, 5000)
# Create SWD object
presence <- prepareSWD(species = "Vultur gryphus", coords = p_coords,
env = predictors, categorical = "biome")
bg <- prepareSWD(species = "Vultur gryphus", coords = bg_coords,
env = predictors, categorical = "biome")
# Split presence locations in training (80%) and testing (20%) datasets
datasets <- trainValTest(presence, test = 0.2)
train <- datasets[[1]]
test <- datasets[[2]]
# Train a model
model <- train(method = "Maxnet", p = train, a = bg, fc = "lq")
# Execute the Jackknife test for all the environmental variables using the
# metric AUC
jk <- doJk(model, metric = "auc", test = test)
# Plot Jackknife test result for training
plotJk(jk, type = "train", ref = auc(model))
#' # Plot Jackknife test result for testing
plotJk(jk, type = "test", ref = auc(model, test = test))
# }
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