SB Nation User Blog: zevkalman

Hoff-POWER's MLB batting average and small sample sizes

zevkalman — Fri, 26 Sep 2008 15:06:56 -0000

A lot of the talk the past two days has been on "small sample sizes" and Hoff-POWER's limited ABs in the major leagues. In May Hoff had a BA of .467, in June he had a BA of .350, and in Sept. he has a BA of .400.

I don't want to belabor any of the arguments on whether or not he should be on the playoff roster, but I just wanted to make sure that some people don't use the words "small sample size" without some understanding of what they mean.

First of all, without getting into the mathematics of probability density functions, let's just say that to know someone's "true" batting average, one would theoretically need an infinite number of at-bats. Practically speaking, statisticians use something called a "95% confidence interval" to estimate when one is 95% certain that something like the batting average lies between a given range.

A good formula for all of this is that if N is the number of ABs, and the player has an observed batting average of BA, then assuming that the estimates of batting average are normally distributed then we can be 95% certain that the "real" batting average (RBA) of that player lies in the interval:

BA - 1.96*sqrt(BA*(1-BA)/N) < RBA < BA + 1.96*sqrt(BA*(1-BA)/N)

What does this mean? Well, Hoff has a current BA of .387 after 62 ABs, which means that we can be 95% certain that if he continues playing at this level, his "true" or "real" BA lies between .265 and .508. If he had more ABs, this "range" would shrink further. For example, Theriot has a BA of .302 after 502 ABs, giving a true range between .264 and .340. Ward has a BA of .216 after 97 ABs giving a range between .134 and .298.

Now, I'm not claiming that BA is an important metric for measuring a good hitter, and I'm not arguing who is the better pinch-hitter, or hitter in special situations. I'm just arguing for discounting other people's arguments on "small sample sizes" since in some sense, a lot of baseball stats can be considered to be based on small sample sizes, especially when one factors in things like lefty/righty splits, etc.

Astros To Receive All Ticket Revenue From Miller Park

zevkalman — Mon, 15 Sep 2008 12:46:47 -0000

As you see here, owner Drayton McLane got his wish to keep all the ticket revenue from the game in Milwaukee:

According to a source familiar with the intense negotiations between Major League Baseball and the teams involved, the Astros will receive the ticket revenue from the games at Miller Park.

Even though the Astros get the revenues from the games, they insisted on wearing their road uniforms and sitting in the visitors dugout in Milwaukee. Today, the Houston Chronicle quoted McLane as saying that the Astros had no choice but to play in Milwaukee. Chronicle sportswriter Richard Justice called the decision to play in Milwaukee "beyond ridiculous" and then wrote that if the Astros miss the playoffs by a game, they will "remember this one". He mentioned that the mood of the Astros players went from "angry to very angry" and then quoted Oswalt as saying: "We’re the only team in baseball that’s going to play 83 road games." Yet, in the same article Justice wrote that:

He [McLane] refused to believe predictions that a monstrous storm was headed for Houston. He wanted those three home games against the Chicago Cubs so badly that his judgment was clouded. Had he acted earlier, had he acknowledged that the Astros and Cubs simply weren’t going to play at Minute Maid Park, this series could have been played at a true neutral site over the weekend.

Good Places To Watch the Cubs While Travelling

zevkalman — Mon, 21 Jul 2008 18:24:40 -0000

Hi there. I just came back from spending 3 weeks in the desert north of Las Vegas on a physics experiment, and I found a restaurant (good breakfast place, also) in the Summerlin area of Las Vegas to watch Cubs games with Cubs fans. It is called "Omelet House" and the owner Iggy is a rabid Cubs fan who has Cubs posters, bats, and other stuff on his wall--including a satellite subscription to as many Cubs games as he can get. Having lived in DC for a number of years where there is NO place I've found to watch the Cubs in a Cubs-centric bar while having a drink, or eating dinner, I was wondering if there are any other places (outside of Illinois and Iowa) where you can do that? I remember being in Boulder, CO once and going to a bar that seemed Cubs-centric, but don't remember any others. Anyone have any tips on restaurants or bars to frequent when traveling on business outside of Chicago that are Chicago-sports-centric?