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What Would a Good Electoral Map Even Look Like?

Using a score he named after the inventor of gerrymandering, one geographer discovers a huge variation in how well congressional districts match up with commuter regions consisting of interconnected urban, suburban, and rural areas.
The difference in "Elbridge scores" between Pennsylvania’s current gerrymandered map and the new map which the state Supreme Court handed down in February suggests that the current map cuts the state up into areas that don’t match very well with commuter-based communities.
The difference in "Elbridge scores" between Pennsylvania’s current gerrymandered map and the new map which the state Supreme Court handed down in February suggests that the current map cuts the state up into areas that don’t match very well with commuter-based communities.Garrett Dash Nelson

Everybody knows that gerrymandering is bad because it unfairly stacks the political decks. In addition to the lopsided electoral outcomes, a gerrymandered map is also objectionable because crazy, mangled voting districts in the shapes of corkscrews or tweezers don’t correspond at all to the relevant geographic units in which we actually live. People have emotional and political attachments to all sorts of geographic entities: jurisdictions like states and cities as well as culture regions like the Bay Area or Appalachia. But who ever introduced themselves a proud resident of NH-02, or got a tattoo with the outline of TN-03?

To quantify the political unfairness of gerrymandering, we can count up partisan demographics and look at election results. However, it’s much harder to test how well or how poorly a map matches with the patterns of human geography. Although many states require the districting process to respect so-called “communities of interest,” how to define and demarcate these communities remains an open question, and so these requirements have rarely exerted much legal force.