arbiter.net question

[Camron Rust]

Originally Posted by Back In The Saddle

There is also another, top secret, zip code field, which only the assigner can access, that is used when calculating your distance to game sites for auto-assigning. Somehow mine got set to another state (perhaps I ticked off my assigner? ), and when I got assigned games, I was due some very hefty mileage checks.

I have also been told that the algorithm for figuring mileage uses a fixed point within the zip code. In my case, that fixed point is many miles farther. I normally mapquest and google maps my journey, and pass that number along to the school. But some schools just use the number from the arbiter, and my check is a little bigger than normal. Can't help 'em out if they don't want the help, I guess.

While I can't tell you how Arbiter does it for sure, I can tell you how I do it on RefTown....

I do it from the geographic center of the zipcode of the official to the geographic center of the zipcode of the school. Databases are available that give precise coordinates (latitude and longitude) of this geographic center. With this data, you can calculate the distance between two coordinates.

The ramifications of this sort of approximation is that the driving distance can be off by +/- half the size of each zipcode.....plus the "as-the-crow-flies" approximation error. (I've been investigation even better methods of approximating distance that eliminates 1/2 zipcode errors). The distance from an official to a school in the same zipcode will come up as 0 miles. The distance between a school and an official who just live on opposite sides of the zipcode boundaries could be 10's of miles.

On RefTown, however, I don't do it "as-the-crow-flies". I have another method that I created that more closely approximates real driving distances....still an approximation but typically with a smaller margin of error.

To calculate precise mileages for all the possible addresses and routes is a pretty complicated and compute intensive task...something you don't really want when you load your page with 40-50 games.