More Math and Baseball

Baseball!Bukiet and Harold wrote a paper entitled A Markov Chain Approach To Baseball, which details their use of Markov models to study hitting order and the effect of trades in baseball. Yang and Swartz wrote a paper entitled A Two-Stage Bayesian Model for Predicting Winners of Major League Games uses a much smaller set of data to perform similar calculations. Alan Schwartz of ESPN wrote about why Barry Bonds 2002 season was statistically without equal, according to Carl Morris of Harvard. You could also visit another webpage which deals with the question “How long should a World Series last?

The Yolo Reflector, a booklet by Arthur Leonard

The Yolo TelescopeOn an unrelated search, I discovered that Arthur Leonard’s treatise The Yolo Reflector had been scanned and made available, including translating all the mathematical formulas into MathML. A very nice job! I have copy of the dead tree version that was mailed to me by Leonard, and it’s good to see this nifty work get wider distribution.

For those of you who may not have heard of them before, a Yolo telescope has two concave mirrors which are tilted, and thereby yield a telescope which is unobstructed. Normally, this would not work very well, as the astigmatism of tilting each mirror would add, but Leonard experimented with warping mirrors into astigmatic figures by use of a warping harness: a mechanical aparatus that bends the secondary mirror into a potato chip like shape (not visibly, but detectably at the eyepiece).

I hadn’t looked at in quite some time. There is an impressive array of articles contributed. I’ll be back again.

Software That Lasts 200 Years

Dan Bricklin, one of the co-inventors of Visicalc, has posted a nice article entitled Software That Lasts 200 Years. He points out that software which helps form societal infrastructure is necessarily concerned more with the long term and total cost of maintenance, and is poorly served by the normal business models which are common in the software industry.

I had a fairly similar notion a while ago. As a recreational programmer, I’ve written dozens if not hundreds of programs for my own enjoyment and experimentation. Every once in a while, I go through and make sure that they all compile and work, and maybe dust one off and extend it in a new direction. Most of the time, this is simple, but occasionally it requires more work. Since I had been working on a simulator for the PDP-1, I hypothesized creating a full machine simulator for an entirely hypothetical machine (probably resembling a MIPS processor of some sort). My software would target this machine, and my work would then merely need to target this emulator.

There are many practical problems with this approach (such as the need to maintain a compiler for the target). It’s hard to maintain the entire stack in some bootstrappable form. Perhaps if I reread Bricklin’s essay with an eye toward increasing maintainability, I’ll make more progress in my thoughts.

Oh well, time for breakfast.