Return the conversion factors between attractivenesses and incoming flows

Some spatial interaction models use conversion factors between attractivenesses and incoming flows to check whether they are at equilibrium (see for instance blvim()). This function returns the conversion factors used to build the spatial interaction model when applicable, and NA otherwise.

Usage

sim_conversion(sim, ...)

Arguments

sim

a spatial interaction model object (an object of class sim)

...

additional parameters

Value

NA or a vector of conversion factors (one per destination location), see above.

See also

blvim(), sim_potential(), sim_residual_jacobian()

Examples

distances <- french_cities_distances[1:10, 1:10] / 1000 ## convert to km
production <- log(french_cities$population[1:10])
attractiveness <- log(french_cities$area[1:10])
model <- static_blvim(distances, production, 1.5, 1 / 250, attractiveness)
sim_conversion(model) ## must be NA
#> [1] NA
dyn_model <- blvim(distances, production, 1.5, 1 / 250, attractiveness)
sim_conversion(dyn_model) ## the default value 1, for each destination
#>  [1] 1 1 1 1 1 1 1 1 1 1