Solitaire, Voting And The Monte Carlo Method

[L. Coyote]

Last edited Wed Sep 9, 2015, 09:28 PM - Edit history (1)

Solitaire, Voting And The Monte Carlo Method
http://www.forbes.com/sites/kevinknudson/2015/09/08/solitaire-voting-and-the-monte-carlo-method/

........... Duke University mathematician Jonathan Mattingly and his student Christy Vaughn created a model. Congressional districts in a given state must divide the population evenly and be “compact.” There are roughly 102785 possible maps that could be drawn in North Carolina (talk about a big number!). So to get a sense of what sorts of outcomes are likely they had to use a Monte Carlo procedure to estimate the probabilities of various results. The upshot: out of 100 randomly chosen districting maps, about 80% had seven or eight Democratic candidates elected, and all 100 had between six and nine. Not once did only four Democrats win. So it seems that the state’s districts might not be drawn fairly after all. ............

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Redistricting and the Will of the People
Jonathan C. Mattingly, Christy Vaughn
http://arxiv.org/abs/1410.8796

We introduce a non-partisan probability distribution on congressional redistricting of North Carolina which emphasizes the equal partition of the population and the compactness of districts. When random districts are drawn and the results of the 2012 election were re-tabulated under the drawn districtings, we find that an average of 7.6 democratic representatives are elected. 95% of the randomly sampled redistrictings produced between 6 and 9 Democrats. Both of these facts are in stark contrast with the 4 Democrats elected in the 2012 elections with the same vote counts. This brings into serious question the idea that such elections represent the "will of the people." It underlines the ability of redistricting to undermine the democratic process, while on the face allowing democracy to proceed.