The interview with Thomas Kuhn that Ultimate Rob recently posted to his site reminded me that, last summer, I had the good fortune of watching Thomas play in a showcase game between Furious George and Sockeye at the Flowerbowl tournament in Vancouver. One part of that game that sticks out in my head is a play in which Thomas threw a short pass into the ground right near his own goal line. When that happened, the first thought that ran through my mind was: “Holy crap, I could have done that! Maybe I should be playing for Furious, too?!” But the difference between Thomas Kuhn and me is not that he is incapable of making simple mistakes. The difference is that he did not spend the next ten minutes of the game thinking about how much he sucked as a player because of one little mistake he had made.

That type of thinking does not come naturally to most human beings. It is hard for us to accept that not every detail of every game actually means something. But the science of statistics tells us that we are not in complete control of our destiny. Mistakes are going to happen, and sometimes they are going to come in bunches. And that sixty yard huck you
just threw for a score? Yeah, maybe that happened because you are truly awesome. But chances are good that you might have just gotten lucky on that one, too.

One of the reasons I wanted to create the database of statistics that I described in my previous post was to help players identify which aspects of their game they were truly good at, and which aspects of their game were just the result of the random chance that is an inherent part of every game of ultimate frisbee.

Through four weeks of play, I have been able to collect data on nearly 7,000 passes in the Calgary Ultimate Spring League. A logistic regression analysis has shown that there are two primary factors that affect whether or not a pass will be completed: (1) the length of the pass and (2) the distance the thrower is from the end zone that he is attacking. The two
influences are pretty simple: (1) the longer the throw, the less likely it is to be completed, and (2) the closer a thrower is to the end zone he is attacking, the less likely he is to complete the pass. These two factors do not interact, which means that they counterbalance each other nicely in a way that prevents the game of ultimate from ever becoming too easy. You can play it safe by chipping your way down the field with short, easy to complete passes, but it’s only going to become harder and harder to do so, the closer you get to the end zone. At some point, you’re going to have to

To help the players in the league visualize how much these two factors influence their own play, I have broken down everyone’s throwing statistics into two different tables. One of these shows the number of “passes on target” (POT) out of passes attempted–along with the yardage gained–on passes of various lengths. The other table shows the same
information for passes made at different spots on the field. Next to each table are posted the league averages for the same tabular breakdowns. This enables players to identify prominent deviations in their passing game from the league norms–the objective being to help each player identify the consistent trouble spots in their throwing game, rather than the
individual plays which may or may not have gone in their favor. A good example is Thomas’ page, which you can find here:

Or you can just poke through the directory of every player in the league:

For myself, I have learned that my completion percentage beyond the halfway point of the field is pretty miserable–63.2%, compared to the league average of 81.5%. That’s a pretty hard pill to swallow, but I also know that identifying what parts of my game need the most work is the first step I need to take to becoming a better player. And then, maybe
someday, I’ll be able to throw one into the ground for Furious George, too. 🙂

Written by Stephen Winters

I grew up in Minnesota and spent lots of time as a kid throwing around frisbees just to see them fly. Somehow, I never played ultimate until I was 25, but I joined a summer league then (in 1999) and haven’t stopped playing since.

When I’m not playing ultimate, I profess linguistics at the University of Calgary, calculate all the baseball stats at, and take pictures of the beautiful things I see in the world around me.