You took the words out of my mouth. In my g/f's Garmin GPS when you initially punch up an address or point of interest the mileage reflects the distance in a straight line. But once you set it as a destination the mileage is recalculated to reflect the driving directions.

Arbiter shows our distances in miles, however we don't got paid mileage so it really doesn't matter. We get a flat travel fee for games worked outside of the city limits.

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? :eek:), 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.

BITS, our assigner has us set our ZIP code and travel limits in the "Travel Limits" screen. This is found under "Blocks". This is nice as I can set one ZIP code for M-F and another for the weekends.

Interesting. I have four different arbiter accounts, and none of them allow me to access "travel limits". Different sports within the same organization (my state activities association) enable different screens within the blocks area.

Ironically, the one sport where I have a definite list of partners I would block, won't allow blocking partners, but allows blocking schools. The one sport where I would really like to entirely block a certain school, won't allow blocking more than 3 individual teams (varsity/jv/soph/frosh and boys/girls are all listed separately).

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.

Sounds like a tough problem to solve, Camron. I just looked up my zip code, and it covers ...oh probably 2-3% of the state. My town is near the edge. Utah is kind of unusual in that the majority of the population live within a fairly narrow corridor running north/south through the center of the state. So the state is framed by huge zip code areas. And since I normally only get mileage when traveling to rural schools, that would seem to make the worst case scenario, the norm.

BTW, would it make more sense to calculate mileage once for each assignment and cache it, rather than calc it on the fly?

Almost, I wouldn't cache it per assignment but per zipcode-pair (a much smaller number of entries than the number of assignments and faster to reference).

In fact, if I put the time in to do that, I'd probably take it a step farther and get zip+4 locations or actual address locations (Latitude/Longitude of the home/work and game locations) if I could find a usable source for the data.

As it is, I do 6 trig functions, 4 floating point multiplies, and a couple other miscellaneous operations. That mileage function is not heavily used at this point so it is not that big of a issue.

For our games, one driver gets paid round trip by the school, who also pays the game fee. For some schools I know the mileage and can fill it out by memory on the pay voucher, for others I set the trip gauge from my house and figure it that way.

It seems like some people are making this way harder than it really is.

He Has A Loophole Named After Him ...
 

My accountant just lets me use the Arbiter mileage. I'll double check with him when I go to visit him on the next visiting day. You may be familiar with his prestigious accounting firm, Cook, Books & Hyde. He assures me that he is, indeed, a Certifiable Public Accountant (CPA), so he must be giving me good advice. When I visit him, I want to bring him a present for doing such a great job on my taxes, so I have to go out and buy a file, and then bake a cake.