Plot how far a monthly projection can be trusted

The companion to plot_projection(): the same cells, panelled by what is uncertain about them rather than by what is predicted. Whichever of the uncertainty surfaces the run produced are drawn, and nothing else.

Usage

plot_projection_uncertainty(predicted, year, month, species, path)

Arguments

predicted

a projection from predict_grid() with uncertainty columns

year

year being projected

month

month being projected

species

species name, for the title

path

where to write the PNG

Value

path invisibly, or NULL when there is nothing to draw

Details

The two panels are deliberately not merged into a single "confidence" layer. They measure different things and are free to disagree in either direction, and the disagreement is the informative part: a cell can be stable across every member and still be extrapolated, because agreement between members trained on the same data is not evidence about ground the data never covered. Blending the two would average that case away instead of showing it.

Diverging colour on the novelty panel, centred at zero, because zero is the meaningful break: above it the model is interpolating, below it the cell is outside the training range on some predictor and the model has no evidence for what it says there.

See also

novelty_surface() for how the novelty panel is computed