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Summary of a collection of spatial interaction models

Source: R/sim_list_summary.R
summary.sim_list.Rd

This function computes summary statistics on a collection of spatial interaction models (in a sim_list).

Usage

# S3 method for class 'sim_list'
summary(object, ...)

# S3 method for class 'summary_sim_list'
print(x, ...)

Arguments

object

a collection of spatial interaction models, an object of class sim_list summary.sim_list()

...

additional parameters (not used currently)

x

an object of class summary_sim_list produced by

Value

an object of class summary_sim_list and list with a set of summary statistics computed on the collection of spatial interaction models

Details

The list returned by the function contains the following elements:

  • median: the median of the collection, as return by the median.sim_list() function

  • distortion: the average distance of all elements of the collection to the median model

  • withinss: the sum of all pairwise distances between the elements of the collection

  • nb_sims: the size of the collection

In addition, if the collection contains non bipartite models, the result has another element, nb_configurations which gives the number of distinct terminal sets in the collection, where the terminals are computed by terminals(), using the "RW" definition.

See also

median.sim_list(), terminals()

Examples

positions <- matrix(rnorm(15 * 2), ncol = 2)
distances <- as.matrix(dist(positions))
production <- rep(1, 15)
attractiveness <- rep(1, 15)
all_flows <- grid_blvim(distances,
  production,
  c(1.1, 1.25, 1.5),
  c(1, 2, 3),
  attractiveness,
  epsilon = 0.1,
  bipartite = FALSE,
)
summary(all_flows)
#> 
#> ── Summary of a collection of 9 spatial interaction models ──
#> 
#> All models have 15 origin locations and 15 destination locations.
#> 
#> ── Median representation ──
#> 
#> ── Median spatial interaction model 
#> Spatial interaction model with 15 origin locations and 15 destination locations
#> • Model: Wilson's production constrained
#> • Parameters: return to scale (alpha) = 1.25 and inverse cost scale (beta) = 2
#> ℹ The BLV model converged after 700 iterations.
#> 
#> ── Homogeneity 
#> distortion: 1.779
#> within variance: 86.926
#> 
#> ── Terminals ──
#> 
#> The list has 7 different terminal configurations