# How we found the best players on our paintball team (Part 4): Creating a Model

At this point in our story we’ve:

This, as we all know, was fantastic! To our knowledge, nobody had ever had this kind of data on a college team’s performance.

Our next challenge was to figure out which individual statistic was most important. We knew that a couple were pretty obvious, e.g. laning, but other than that it was anybody’s guess.

Today its now who can shoot the most paint behind a bunker. Back then it was chess, who can out smart the other. Its now a game of twelve year olds who are beating the hell out of me.
- Ron Kilbourne

Many years ago I read a page on ELO rankings in Foosball. It was a simplified version of the chess ELO ranking system. For those of you who have never played competitive chess (I never have), the idea behind it is that everyone gets a “number” that indicates how good you are and works under the following basic assumptions:

• Given the rankings of two opponents, you can calculate the odds of each player winning easily based on a statistical curve.
• If the higher ranked player wins, the rankings go up for the winner and down for the loser. The key point being only a little in both directions.
• If the lower ranked players wins, his ranking goes up a lot and the higher ranked player goes down a lot.
• a “little” and a “lot” are calculated statistically
• This means that “upsets” and “sure things” are weighted accordingly.

If you have a statistics background, I highly recommend reading more about it.

For the rest of us, let’s get back to the dirt and paint of the real world.

I, very modestly, decided to call this new ranking system as applied to paintball the “Alexpotato Rating”. Everyone was assigned a “middle” value of 1500 Alexpotato Rating points (the low being zero and the high being 3000). Each practice point was considered an individual event that updated each player’s ranking based on the formula described above.

Some of you might be asking “That makes sense for single players but paintball is a team sport. How do you make calculations based on a group?”

Excellent question!

I took the idea from the Foosball folks and just averaged the the ranking for each player. After ten or so points, we looked at how the rankings played out and we were surprised to see that for most of the players, the ones we thought were better matched closely with the AP Rating.

This let us know that we were on the right track.

The big question was: what made them better?

We answer that question in the next post.