## Optimizing a Swim Meet: Traveling Salesmen and Asexual Mutants

You wouldn't think there is much to swimming analytics. Compared to sports like baseball or football, swimming is extremely deterministic. Swimmers tend to have a certain speed in each stroke, and they vary only slightly around that tendency from meet to meet. There are no interactions with teammates, collisions with opponents, or bouncing balls to worry about. But it turns out that there's more to aquametrics than meets the eye.

My kids are on a summer swim team in the local league. It's a great activity--exercise, a bit of healthy competition, and all four of my kids and step-kids are on the same team for one season out of the year. It's a lot of fun for everyone.

It's complicated, though. There are five age groups for both boys and girls for a total of ten competition groups. There are 4 strokes (fly, back, breast, and freestyle). Each swimmer is assigned to one of three classes for each stroke. The A class has the faster kids, the B class the next faster kids, and the C class has the rest. First, second, and third place in each stroke-class (for each age/gender group) earn points for the team. The A, B, and C classes all count equally, in the spirit of the league. It's 5 points for a 1st, 3 for a 2nd, and 1 for a 3rd, regardless of class. This way, nearly everyone's performance can affect the outcome of the meet.

There's only one strategic variable in the meet. Each swimmer can only swim in 3 of the 4 stroke events in the meet. In other words, each swimmer has to skip one of the four strokes for the day. The manager of each team seeds the meet a couple days beforehand. You'd think that the best strategy is to have each swimmer participate in their 3 best strokes. But that's not the case.

## Do Those Who Deny Advanced Statistics Even Watch the Game?

### Stochastic Football

We understand your hostility. Maybe we're dangerous. Would it comfort you if I guaranteed that we are dangerous? And maybe we're dangerous to you. Do you prize your memory, your experience? Do you have knockdown, drag-out fights about what just happened, what you saw, what you know? Are you infected with certainty? Does this, this quote to follow, does it resonate within you, move you to potency, make you want to pressure wash something?

Inaction breeds doubt and fear. Action breeds confidence and courage. If you want to conquer fear, do not sit home and think about it. Go out and get busy. —Dale Carnegie

## Joint Statistical Meetings

I've been invited to speak at the Joint Statistical Meetings this year, an annual event hosted primarily by the American Statistical Association. It will take place August 3-8 in Montreal. The theme of the talk is Big Data in Sports. My talk is scheduled for Monday the 5th. So if you'll be in Montreal for the conference, please come by and say hi.

Gagnez le jour, Alouettes!