Compactness
When you click on the “Analytics” command in DRA 2020, the “Compactness” section helps you understand the degree to which the districts in your map are geometrically compact (or not).
You’ll see three parts.
Metrics
The first part shows two prominent measures of compactness:¹
Rating
The second part presents the rating:
Using historical data and ideal values, both raw values are normalized to a [0–100] scale where bigger is better and then averaged to create a single rating.² The thermometer shows that rating which is further categorized below using a 5-point scale.
Notes
The third part add two bits of context:
- How people judge compactness — The first note reports how people intuitively judge the compactness district shapes, using a common “know it when you see it” understanding of compactness.³
- Political geography — The second note highlights a frequent tension between compactness and proportionality due to political geography.
You can also see district-by-district compactness measurements in the Compactness section of Advanced view.
Footnotes
- See Measuring District Compactness in PostGIS and Measuring Compactness.
- For more details and context, see Ratings: Deep Dive.
- See How to Measure Legislative District Compactness If You Only Know it When You See It (Kaufman, King, and Komisarchik, forthcoming). We invert their [1–100] smaller-is-better ranks so that bigger is better like our other ratings.