Comment by at_a_remove | Hacker News Reader

Comment by at_a_remove | Hacker News Reader

The difficulty I always thrash around with is: proportional by area or proportional by population? I used to do some crime maps and some areas would look quite crime-ridden ... because they were areas with very little population, as the census counts it, like parks and such, so the crime would look rather high. So dividing by population isn't the cure-all, but it beats nothing. For giggles, I would do crimes in a given region, crimes in a region divided by that area, and crimes in a region divided by the population in that region. Very different-looking results.

I have often considered dividing by some kind of combination of area and population, but even that seems not quite right. Disregarding "victimless crimes," much crime is interactive: two or more parties must be involved, therefore the population ought to have some kind of exponent attached to it, like particles bouncing against one another in a container.

I never did puzzle this out, I am sure brighter minds than I would have come to some conclusions.

The answer ends up being: Why not Both? Both are useful but tells us different things. For COVID-19, the number of infections has real meaning regardless of its proportion of the population: Each are instances of viral infections that can spread that infection further. But proportion infected can give information about virulence, etc.

>therefore the population ought to have some kind of exponent attached to it, like particles bouncing against one another in a container.

Population squared? That gives you the number of potential connections.

That was my first thought, yes, but then I think area ought to be involved somewhere; if the area is large enough, even a medium population will not have people ("particles") interacting ("colliding") as often.

In the rather clumsy taxonomy of crime I created from the UCR, most violent crime -- excepting suicide -- would be collision-based. Some drug crimes like possession would not be collision-based (although it could be argued that possession involves buying which involves another person) while drug sales would be. Crimes against property are interesting -- is that another person by proxy, or should that merely be collision-less?

What about something like property crimes/100,000 people and violent crimes/100,000 people? Disease rates are often reported in such ways like in the article posted the best map had rates/100,000 and not strictly population or area.

Alaska and Washington DC have roughly the same population. But there are many more actual connections between people in DC than in Alaska.

Where connections could eg mean: two people come in close enough proximity with each other to spread a virus.

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