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by jcwilde 2510 days ago
I fail to see how "per capita per square mile" is a useful measure.

_Anything_ measured in that way would show densely populated area vastly outnumbering rural areas, perhaps with the exclusion of things that essentially don't exist in cites, such as "number of farms per capita per square mile".

The measure appears to be concocted specifically for Lying With Statistics™.

1 comments

Should proximity to potential assailants not be taken into account?
The "murders per capita per square mile" metric really gets to the heart of the question on every American's mind: what percentage of face-to-face interactions are murders?
If you wanted to track that you'd need to do the opposite of what GP is suggesting.

That is, a dense urban area would have more face-to-face interactions than a sparse rural one. Given two areas with equal levels of per-capita violence, it would then follow that the more sparsely populated one would have more violence per face-to-face interaction, not less.

Right, I guess you'd actually want a measurement like "murders per population density" or "murders per (person per square mile)". Or, as it's more commonly known, murder-hectares per capita.

Murder-hectares per square capita? Murder-capitas per hectare? I'm not actually sure how the dimensional analysis works out.

This is absolutely absurd. We're talking about the US here, so it would be murder-acres, and that just sounds like a country club you really shouldn't join.
Wouldn't that assume that murderers do some kind of random walk, and randomly kill some person they happen to get close by?

I'm sure there are those, too, but IIRC in most violent crime the attacker and the victim know each other. Do people have substantially bigger social circles in cities?