02 / THE MECHANISMS
State field model
Adjust the forces. Explore how dialect patterns could evolve.
Change across birth cohorts
Population-weighted frequencies among the included variants.
HOW TO READ THIS MAP
A sandbox for mechanisms.
This first version integrates the deterministic mean-field equations described in the supporting research. It starts from the 1950 empirical field, aggregated into 240 population-weighted regions for responsive interaction. The 4,000 map cells inherit their region’s simulated value.
Migration uses the Burridge and Vaux gravity-kernel parameters, recalibrated on the reduced mesh. Local copying has a 100 km length scale. The sandbox assigns an experimental east–west coefficient to each variant, forming a regional bias vector. It is not the study’s fitted spatial bias field. No stochastic noise or parameter fitting runs here. Results illustrate mechanisms and do not reproduce the map-based study’s full-resolution forecasts.
KL divergence compares simulation with the empirical field aggregated to the same regions (unweighted region mean, in nats). Smaller values indicate closer distributions; it is not a validated forecast score.