Monday, December 31, 2012

Pitcher Fatigue, Part 2: The Top 10

Earlier, I wrote a post on the declining effectiveness of starting pitchers as they get deeper into games, postulating that it came from two major sources: the first being the fact that it's difficult to throw 100 pitches in a night without your arm getting temporarily tired, and second that the second time a batter sees a pitcher, they already know what type of stuff the pitcher is throwing and so are better able to hit it.  Overall I estimated that by rotating pitchers frequently each game so that no pitcher went through the lineup more than once, a team could save about 5.6 wins each season (ignoring other effects, like the fact that if you're in the NL you get to pinch hit more often).

Also, starting with this post I'm going to make a conscious effort to switch from using OPS as my default batting stat to wOBA. wOBA, which is on the same scale as on-base percentage, is basically a version of OPS that uses more accurate weightings for events.

______________________________

On average, in 2012, the first time pitchers saw a batter they allowed a wOBA of about 0.338.  The second time they saw those batters, the wOBA jumped to about 0.350, for a difference in wOBA of about 0.011.  I'm going to name this statistic--wOBA for second plate appearances minus wOBA for fist--w-diff.

So the league average w-diff in 2012 was about 0.011.  But different pitchers had different w-diffs.

Look, for instance, at R.A. Dickey.  Dickey is a knuckleballer, and so one would expect hitters to be unusually bad the first time they see him--they have no practice hitting a knuckle-ball--but to get much better the second time, meaning one would expect him to have an unusually large w-diff.  And, in fact, he does have a large w-diff over his career if you ignore all of the seasons in which he didn't have a large w-diff, which is a thing that makes a lot of sense to do if you have a personal vendetta against the year 2011.


Sunday, December 30, 2012

Being a Utilitarian, Part 2: Conventional Charities

This is the second post in a series on actually being a utilitarian in the world; for the first post, look here.  Also, for a more theoretical series on utilitarianism, look here.

______________

So, say that you're a utilitarian, and you're wondering what to do with your life.  (Even if you're not a utilitarian but are wondering what to do with your life, most of this will apply.)  What should you do?  What, in the current society, can an individual do to make the world a better place?  And what causes should you care about?

Is there anything you can do with your life to make the world a better place?


Sunday, December 23, 2012

Less Stupid Use of Pitchers: Pitcher Fatigue

A while ago I wrote a post about one of the most unenlightened areas of baseball strategy: the use of pitchers.  I proposed eliminating the distinction between starting pitchers, middle relievers, and closers in favor of a system that just uses a set of pitchers, each pitching different total numbers of innings, but no single pitcher pitching more than a few innings in a game; in other words, a starter would now throw two innings every few games instead of seven innings every five games.

The advantages of this, as I see it, are four fold.

1) If you're an NL team, you can pinch hit for your pitchers whenever they come up.

2) Pitchers don't have to throw 100 pitches in a game.

3) Batters never get to see the same pitcher twice in a game, and so can't get used to their pitches.

4) You can get the pitcher-batter match-ups you want all the time, instead of being stuck with your same pitcher the first three times through the lineup.

In the first post I estimated the size of effect (1): pinch hitting for you pitcher every time would let you score about 0.2 more runs per game, translating into about 3.2 wins per season (the difference between a .500 team and a .520 team).

Now I'm going to look at effects (2) and (3).

Tuesday, December 4, 2012

Being a Utilitarian, Part 1

I've written a series of posts about the different types of utilitarianism arguing for aggregate, classical, act, one-level utilitarianism.  I haven't, however, talked at all about what it would mean to be a utilitarian in the real world.

In the real world, obviously, you aren't faced with a series of trolley problems or utility monsters.  If you don't think about it very much, you might conclude that utilitarianism isn't actually useful because you can't calculate the total utility of each possible action.

However, as it turns out, utilitarianism can be useful even if you don't know the exact state of the universe.

In future posts I'll examine thornier, more wide-reaching issues, but for now I'll just talk about one issue--the first issue that I actually thought about in utilitarian terms.  For people familiar with utilitarianism it probably won't be that interesting or revolutionary, but it's a good way to remind yourself that just because a theory is complicated doesn't mean approximations can't be useful.  (It also parallels an argument Peter Singer has made on the subject.)


Re-starting the blog, and results of the second contest

As you may have noticed, after a hiatus while the school year started, I'm back to blogging.

First, I never resolved the second contest.  No one solved the puzzle but Matt Nass made partial progress, so he gets 3 Shadow-points.  I'm going to leave the puzzle open and if anyone solves it they get one Shadow-point.  Here's the puzzle again, with a little bit filled in as a hint:

Instructions for the puzzle are here.

Also, I think that weekly was probably too frequent for the contests, so they're going to change to bi-weekly; I'll have another one out soon.

If there's anything you want me to write about, put it in the comments here.

Contributors