Dr. Z's racetrack module for 41C

[David Hayden]

Thanks Thomas, Bob and Gene. I'm embarrassed that I didn't find this stuff myself. Strangely, googling "41c racetrack" didn't reveal the manual or the rom image. Or maybe I just didn't look through enough pages.

There's a funny backstory here. In the summer of 1984 I was renting a house in Mountain View CA with some other Stanford students. One guy's hobby was studying gambling strategies. As I remember it, Tim said he learned about a really interesting strategy for racetrack betting that was in an upcoming book. The strategy was based on a single, verifiable principle: that the betting totals on the toteboard accurately reflected the probability of a horse winning. Based on this you could compute the probability of them placing or showing (coming in 2nd or 3rd) and with the toteboard data you could predict the payoff of the bets. Sometimes the payoff for placing or showing was higher than the probability and that made for winning bets in the long run. The strategy even gave recommended bets as a percentage of your total money available.

Tim said that all that was missing was a way to make the computations. Naturally I pulled out my 41CV and said "give me the formulas. I'll program them.

So I did, and we were literally off to the races!

When we got there we quickly realized there was a logistical problem. It took time to key in the toteboard numbers and it took time for the program to run. After a little trial and error, we came up with this procedure: 3 minutes(?) before post time I'd start keying in the numbers from the left side of the toteboard and Tim would write down the numbers from the right side. When my keying met his writing, we'd get in line for the betting window, Tim reading the numbers to me as I frantically keyed them in.

Now pause to get the visual here. A racetrack is a pretty seedy place with lots of cigar chewing people betting their paychecks away. Here are two college kids with a funky looking computer thing, working their way up the betting line. One kid is reading numbers from a notebook: "10,234... 8,443... 19,433..." The other is frantically keying the numbers into the computer. We really turned heads. Occasionally we'd near the betting window and the computer would beep. I'd read the display and turn to Tim. "No bet," I'd say, and we'd proceed to leave the line. People got nervous when "the computer" said not to bet.

And so it went. We won some. We lost some, but it was obviously a very memorable day for me. When I saw a "racetrack" ROM for sale on TAS the other day, I looked into it and the more I looked the more I became convinced that this ROM was based on the same strategy.

Sadly, my program is lost. It looks like I overwrote the cards that it was saved on. I found one card that appears to have the last part of the program: It displays "SHOW:" and a number.

And since everyone always asks, no, we didn't make money that day, but the loss was entirely due to one fluke race. One horse was really REALLY heavily favored to win. We placed a show or place bet on it. Coming into the final stretch the horse was leading and then it just lost it, slowed down and fell way back.

Tim in the house we rented.
   

Me in Massachusetts that same summer.