My Jeopardy! Strategy Advice To IBM - Part 6

Ed Toutant Report on Watson Jeopardy! Visit – September 17, 2010

BUZZER PERFORMANCE

A lot of Jeopardy! players will tell you that the game winner is determined by the buzzer, since most of the players know most of the answers.  There is no doubt that the buzzer is a huge part of the game.  Watson’s buzzer appeared to perform well, but I was left with a lot of unanswered questions about it. 

I assume, but was never explicitly told, that Watson receives an electronic signal to indicate that his buzzer is now active, and that it arrives at the exact time that the light is switched on.  In theory, Watson could be given a handicap by delaying his activation signal to give humans a better chance of buzzing in, but I assume that is not being done.  Since the signal travels at roughly the speed of light, the only real delay in activating Watson’s buzzer is the time it takes for the solenoid to depress the buzzer button.  I would be very interested in knowing how long that motion takes.  Is it just a few milliseconds, or more like a typical human reaction of 200 milliseconds? 

In a buzzer race between Watson and a human opponent, the only way the human can win is if he has nearly perfect timing and anticipates the lights to buzz in during the brief window when Watson’s solenoid is still being activated.  The shorter that window is, the less chance there is of a human beating Watson to the buzzer. 

My very first job at IBM was to develop an electromagnetic print hammer for a daisy wheel printer.  I did a lot of theoretical calculations, exotic alloy selection, instrumentation and testing to produce the fastest possible actuator for that application.  The print hammer could accelerate a steel projectile from rest to maximum velocity and travel about 5 millimeters in 2 milliseconds.  That seems pretty similar to what Watson is trying to do to actuate his buzzer.  Is Watson’s buzzer activation time in that same range?  If not, I think it could be, with an optimized design.  As long as it’s less than about 10 milliseconds, I wouldn’t worry much about it, but if it’s a lot longer than that, it would be an opportunity for improvement.

I noticed that Watson sometimes hit his buzzer only once, and sometimes hit it multiple times in rapid succession.  I asked a couple people why that was, but never got a clear answer.  If Watson is always reacting to the buzzer activation signal, I can’t think of any situation where more than one buzz would be necessary.  Am I missing something here?