http://groups.yahoo.com/group/election-methods-list/message/9223
Thumbnail sketch of the proposed idea:
1) Treat the census blocks as "atoms" of the eventual districts, i.e. they cannot be split up into two districts.
2) Form a graph of the states where the nodes are census blocks, and the edges represent physically adjacent census blocks.
3) Weight each edge by the amount of road connectivity between the adjacent bolocks. The simplest metric would be number of lanes of traffic that fall on the dividing line. Basically, you want the edge weight to represent how connected those two census blocks are in reality. Ideally, what you'd want is a count of how many people cross the border per year, but that's obviously unrealistic, so the road bandwidth is a good approximation.
4) When you set up districts, you are essentially taking the large graph of the entire state and dividing it into several small sub-graphs which each represent a district. To do so, you cut every census block-to-census block edge along the district boundary.
5) THE AUTOMATED ALGORITHM would take the weighted graph that represents the entire state, and divide it up into the equal population solution THAT MINIMIZES the total weight of the severed edges.
Such an algorithm may be difficult to write, but writing a program that could iterate on an approximate solution could be pretty easily.
-Adam
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