Can't answer questions, didn't need an answer anyway
Via Eurekalert, one of those computerized "game theory" studies attempts to answer an old question that doesn't really need answering. "Game theory" can't answer any questions, so the effort is bilaterally futile.
This correlation is well established:
A language that covers a wider territory with more people tends to have simpler and more regular grammar.
We don't need research to establish the correlation. We could use some analysis of the
mechanism of causation.
One direction of causation is obvious but hard to establish experimentally. A simpler language is easier for newcomers to learn "well enough", so it will spread faster. English spreads faster than Chinese or Russian for this reason.
The other direction is more subtle. Simplification doesn't arise from increased
quantity of speakers. Simplification arises when populations speaking different languages
mix and merge. The 'invasion' can go either way. It's the intersection that counts.
When Roman soldiers brought Latin to areas speaking Celtic or Teutonic, the Latin lost its noun cases. When French soldiers brought their simplified Latin to England, English lost its noun cases and adopted French plurals.
Labels: defensible cases, Language update