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Data preparation

Functions for sampling background/pseudo-absences points and thinning the data.

sample_background()
Sample background points for SDM analysis
sample_background_time()
Sample background points for SDM analysis for points with a time point.
sample_pseudoabs()
Sample pseudo-absence points for SDM analysis
sample_pseudoabs_time()
Sample pseudo-absence points for SDM analysis for points with a time point.
thin_by_cell()
Thin point dataset to have 1 observation per raster cell
thin_by_cell_time()
Thin point dataset to have 1 observation per raster cell per time slice
thin_by_dist()
Thin points dataset based on geographic distance
thin_by_dist_time()
Thin points dataset based on geographic and temporal distance
make_mask_from_presence()
Make a mask from presence data

Choice of predictor variables

Functions for removing collinearity and visualising the distribution of predictors.

filter_collinear()
Filter to retain only variables that have low collinearity
plot_pres_vs_bg()
Plot presences vs background
geom_split_violin()
Split violin geometry for ggplots
dist_pres_vs_bg()
Distance between the distribution of climate values for presences vs background

Recipes

Functions for recipes with spatial SDM data (additional steps can be added with standard recipes functions).

recipe(<sf>) spatial_recipe()
Recipe for sf objects
check_sdm_presence()
Check that the column with presences is correctly formatted

Models specification

Predefined model specifications (custom models can be added with standard parsnip model specifications).

sdm_spec_glm()
Model specification for a GLM for SDM
sdm_spec_gam()
Model specification for a GAM for SDM
gam_formula()
Create a formula for gam
sdm_spec_rand_forest() sdm_spec_rf()
Model specification for a Random Forest for SDM
sdm_spec_boost_tree()
Model specification for a Boosted Trees model for SDM
sdm_spec_maxent()
Model specification for a MaxEnt for SDM
maxent()
MaxEnt model
regularization_multiplier() feature_classes()
Parameters for maxent models

Data splitting

Functions for splitting the data into folds (in additiona to standard spatialsample functions.

spatial_initial_split()
Simple Training/Test Set Splitting for spatial data
blockcv2rsample()
Convert an object created with blockCV to an rsample object
check_splits_balance()
Check the balance of presences vs pseudoabsences among splits
autoplot(<spatial_initial_split>)
Create a ggplot for a spatial initial rsplit.
grid_offset()
Get default grid cellsize for a given dataset
grid_cellsize()
Get default grid cellsize for a given dataset

Metrics

Specialised metrics for SDM, and methods of metrics from yardstick adapted to work on sf objects

sdm_metric_set()
Metric set for SDM
optim_thresh()
Find threshold that optimises a given metric
boyce_cont() boyce_cont_vec()
Boyce continuous index (BCI)
kap_max() kap_max_vec()
Maximum Cohen's Kappa
tss_max() tss_max_vec()
Maximum TSS - True Skill Statistics
tss()
TSS - True Skill Statistics
average_precision(<sf>) brier_class(<sf>) classification_cost(<sf>) gain_capture(<sf>) mn_log_loss(<sf>) pr_auc(<sf>) roc_auc(<sf>) roc_aunp(<sf>) roc_aunu(<sf>)
Probability metrics for sf objects

Ensemble

Functions for creating an ensemble selecting the best set of parameters for each model.

simple_ensemble()
Simple ensemble
autoplot(<simple_ensemble>)
Plot the results of a simple ensemble
repeat_ensemble()
Repeat ensemble
add_member()
Add best member of workflow to a simple ensemble
add_repeat()
Add repeat(s) to a repeated ensemble
collect_metrics(<simple_ensemble>) collect_metrics(<repeat_ensemble>)
Obtain and format results produced by tuning functions for ensemble objects
control_ensemble_grid() control_ensemble_resamples() control_ensemble_bayes()
Control wrappers
explain_tidysdm()
Create explainer from your tidysdm ensembles.

Project SDM to present, past and future

Functions for making predictions.

calib_class_thresh()
Calibrate class thresholds
predict(<repeat_ensemble>)
Predict for a repeat ensemble set
predict(<simple_ensemble>)
Predict for a simple ensemble set
predict_raster()
Make predictions for a whole raster

Managing extrapolation

Functions for managing extrapolation.

clamp_predictors()
Clamp the predictors to match values in training set
extrapol_mess()
Multivariate environmental similarity surfaces (MESS)

Other

Additional helpful functions.

niche_overlap()
Compute overlap metrics of the two niches
km2m()
Convert a geographic distance from km to m
y2d()
Convert a time interval from years to days
filter_high_cor()
Deprecated: Filter to retain only variables below a given correlation threshold
pairs(<stars>)
This is a wrapper around graphics::pairs() that accepts stars objects. It is adapted from a similar function in the terra package.

Example data

Example datasets and simple models used in the documentation

horses
Coordinates of radiocarbon dates for horses
lacerta
Coordinates of presences for Iberian emerald lizard
lacertidae_background
Coordinates of presences for lacertidae in the Iberian peninsula
lacerta_ensemble
A simple ensemble for the lacerta data
lacerta_rep_ens
A repeat ensemble for the lacerta data