Sightings-per-unit-effort (SPUE) effort proxy, per H3 cell (R reference)

Presence-only effort proxy: within the spatial footprint of a higher-order "effort" taxon (e.g. all Cetacea, from multi-species surveys), the fraction of records that are the target taxon. spue = n_num / n_den where the denominator is every record of the effort subtree in the cell and the numerator is the subset that are the target subtree. This is the pure-R reference pinned to obis_spue_sql() by the package tests.

Usage

calc_spue(df, num_aphiaid, den_aphiaid)

Arguments

df

data frame of species-level records with columns cell, aphiaid, records (as in occ_h3).

num_aphiaid

integer AphiaIDs of the target subtree (already resolved via obis_taxon_children()).

den_aphiaid

integer AphiaIDs of the effort subtree (denominator).

Value

data frame with cell, n_num, n_den, spue; only cells with effort records (n_den > 0) are returned.