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Comment by jasongill | Hacker News Reader

I am not a cartographer or any type of a data visualization expert, but isn't the advantage of the hexagon map - the fact that it "highlights trends that are often masked by the geographical quirks of actual state boundaries" per the article - negated by hexagon county maps?

For example, California has 58 counties, but Kentucky has 120. That means that the "resolution" of the data in California is half as accurate as the data in Kentucky despite having ten times as many inhabitants and 4 times the land area.

Basically, by switching to hexagon county maps, aren't we actually amplifying the problem that hexagon state maps try to solve and making it worse, not better?

(A good article and good examples OP but I just don't personally see how the hexagon county map is an improvement, but again I am not an expert in this field)

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You're correct that increasing resolution to the county level can inflate the size of states with more counties. This kind of map wouldn't be appropriate for a state by state comparison at all; instead, it's more useful for a county by county comparison. It's just a different resolution of administrative boundary and there are limits to that.

A lot of U.S. data is reported at the county level and comparing across regions within or across states without worrying about the geography or shapes of different counties can sometimes be helpful. Adding population as a size dimension and filtering to a single state can also help mitigate the distortions.

> For example, California has 58 counties, but Kentucky has 120. That means that the "resolution" of the data in California is half as accurate as the data in Kentucky despite having ten times as many inhabitants and 4 times the land area.

Kentucky also simply looks larger, which over-indexes its importance. I can't really think of any data that I would want visualized by county directly, especially data about people. In California alone, there is a 9000:1 population variance between the largest and smallest county.

It helps if you have a dataset that goes by county, and a lot of data in the US has it's highest resolution at the county level.

ZIP codes or Census blocks would be better, but very few datasets go into that level of detail.

ZIP codes (ZCTA) are uniquely awful for many reasons.. It would be better to avoid them when possible IMHO

Yeah, an important but little-understood fact about ZIP codes is that they are not an area, but a collection of points (≈mailboxes) and polylines (delivery routes); this is because they were created by the post office, who care about logistics, not land. You can try to impute geographical location from them and this mostly works, but there are fun edge cases such as an area where the streets going in one direction are in one ZIP code and all of the cross streets in a different one. The code for an address can also be changed at USPS’s convenience (making comparisons over time difficult); in extremely rural areas “your ZIP code” may be whichever town you prefer to pick your mail up from.

(My favorite fun fact about ZIP codes: 12345 is the General Electric headquarters and factory in Schenectady, New York. They get a lot of mail addressed to Santa Claus.)

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