What good teams are good at | Boston.com
Here's another cool graphical presentation. In this case, it's a historical look at team performance in different stat categories. The default is world series champions (surprise--they tend to be better than average at everything!), but you can just look at the Reds. Reds teams have historically had better than average run prevention, but poorer than average offense. Run scored is funny, though: below average from 1920-1950, but then huge surge from 1950-1978 or so. Recently, we've been more below- than above-average. The 1990 team was dead on average. Hat tip to Rob Neyer.
Game by Game Winning Percentages - Visualization
Awesome interactive graphic showing the progression of 2009 team winning percentages, and how teams eventually settled on their final winning percentage. Love the presentation. Only suggestion would be to hold the red dotted line constant (or insert another dotted line) at 0.500. Hat Tip to Adam Darowski.
The Baseball Analysts: How Do Experts Make Their Predictions?
Fun economics/game theory piece by Sky Andrecheck on what factors go into how sportswriters make their picks of division/wild card winners. He argues that it's probably not all just about choosing the best team...sometimes, it's more about choosing an underdog in the hopes of the chance to look like a genius.
Baseball Prospectus | Manufactured Runs: April is the Cruelest Month
Nice, short piece by Colin Wyers talking about why we shouldn't read too much into April statistics. This is the kind of thing that we all know...but in practice it's hard to act rationally! The moral of the story, however, is not to worry about Jay Bruce, folks.
Beyond Batting Average: A Review
David Gassko's review of Lee Panas' new book "Beyond Batting Average: Baseball Statistics for the 21st Century." I had the opportunity to give feedback on an early edition of this book, and I'll echo most of David's positive comments: it is a terrific resource, giving you the lowdown on almost every major important statistic, what it means, how it’s calculated, and where you can find it. It's extremely current, well-researched, and up to date. I highly recommend it. (full disclosure: Lee discusses some of my work on catcher fielding in the book).
John Walsh returns with a fascinating look at the strike zones of umpires. He finds that umpire strike zones change dramatically depending on the count. There's selection bias here, potentially, as well as possible pitch type effects. But still, it's a huge effect, and I think at least some of this has to do with the behavior of umpires. Whether it's compassion or, as a commenter mentioned, anticipation on the part of the umpires is hard to say.
Very impressive work by Mike Fast quantifying the effect that changes in fastball velocity have on pitcher performance. He finds, not surprisingly perhaps, that changes in velocity have large effects on pitcher performance. Two terrific nuggets to share from this work. First, starting pitchers improve on average by one run per 9 innings for every 4 mph improvement in velocity, whereas relievers improve by one run per 9 innings for every 2.5 mph improvement in velocity. Second, average MLB fastball velcoity is up by a mind-boggling 1 mph since 2007. 1 mph is huge, folks: MLB today has harder throwers, and probably better throwers, than we it did just a few years ago.
Tidbit regarding fastball improvements: Homer Bailey increased his fastball velocity by 2-3 (depending on your source) mph between 2008 and 2009, averaging 94 mph. Yesterday, he was sitting at 92.7 mph, but hit topped 94 mph many times.