Download and optionally downscale the friction surface layer to conduct location-allocation analysis.

This function retrieves the friction surface layer from the Malaria Atlas Project database and optionally downscales it to the spatial resolution of the analysis using road network data from OpenStreetMap. The function returns the friction surface layer, the transition matrix, and the geocorrection matrix.

Usage

friction(bb_area, mode, res_output, dowscaling_model_type)

Arguments

bb_area

A spatial object representing the area of interest.

mode

The mode of transport. Options are "fastest" and "walk".

res_output

The spatial resolution of the friction raster (and of the analysis), in meters. If <1000, a spatial downscaling approach is used.

dowscaling_model_type

The type of model used for the spatial downscaling of the friction layer. Options are "lm" (linear model) and "rf" (random forest).