The traveling salesman problem is afavorite math conundrum: if a salesman has to visit a bunch of cities, how doyou get him to all of them once via the shortest possible route. But thetraveling salesman's predicament pales in comparison to figuring out the bestways to get four-man crews of umpires to every major league baseball game. Aresearch team attacked the problem for the last few years. Their solutionappears in Interfaces. It's a journal of operations research.

 

In addition to minimizing travel, here aresome of the umpire constraints. Crews should visit each MLB city at least once.They should work each team at home and on the road. They should not work morethan 21 days in a row. They should not ump any one team’s games for more thanfour series all year. There are plenty more.

 

The researchers first had to develop thequestion, dubbed the "traveling umpire problem." They usedbrute-force computation and heuristics for their solutions. The result was goodenough for Major League Baseball to adopt the last three seasons. Previously, aformer umpire made the schedule. That guy is out.

 

Thanks for the minute. For ScientificAmerican’s 60-Second Science. I’m Steve Mirsky.