Selection bias with Derek Jeter’s fielding: bad stats, memorable moments

As Derek Jeter’s career winds down, one baseball pundit wrestles with how Jeter’s defense numbers are so bad even as we remember some of his great fielding moments:

Data-mindful observers couldn’t figure out why the decorated Yankee kept winning those Gold Gloves and garnering raves for his defense. Stats such as Ultimate Zone Rating and Defensive Runs Saved didn’t merely suggest that Jeter was overrated; they pegged him as downright terrible. Even the best glovemen lose range as they age, which means Jeter actually hurt himself by playing past his 40th birthday and seeing his career defensive totals dip as a result, but the figures are unnerving regardless. Based on Baseball-Reference’s Runs From Fielding, which is based on DRS, Jeter’s combination of subpar defense and exceptional longevity don’t merely make him a defensive liability; they make him the worst defensive player relative to others at his position in baseball history.

That ranking is incredibly hard to fathom because of a very human weakness: selection bias. People remember a few extraordinary events, then ignore or even repress the information that might contradict that initial impression. With Jeter in particular, it’s nearly impossible to make the visceral reactions agree with the data, because Jeter has pulled off some of the most incredible defensive plays we’ve ever seen.

How to put this all together?

So really, it’s OK to agree in part with both sides of the argument. Even if we acknowledge the flaws of advanced defensive stats that aren’t yet based on play-by-play data or dispute the claim that Jeter was the worst ever, we can comfortably say he was overrated defensively by many people for many years, and cost the Yankees their share of outs. But we can also say that every huge-leverage play like The Flip negated a handful of squibbers through the infield during random April games in Cleveland, even if they left him as a net-negative defender on the leaderboards. Jeter might not have deserved five Gold Gloves, but he does deserve credit for crafting memorable plays that can’t simply be chalked up to coincidence or luck.

In other words, memorable plays that lead to key victories can go a long way to wiping out more objective data over a longer period of time. Of course, this is true across a broad range of contexts beyond baseball; showing unusual urban crimes and police responses as “normal” could have a similar effect on television viewers. In the long run, perceptions may have less of a shelf life as people who witnessed those events – like “The Flip” – stop remembering them or die and the data lives on.

The end of the Lou Pinella era

As I listened to the Chicago Cubs pregame on WGN Radio, I heard the news that Lou Pinella is resigning after Sunday’s game against the Braves. A few of my thoughts about the Lou Pinella era:

1. This resignation spells the true end of this four year era of Cubs baseball. As the players leave (Lee, Theriot, Lilly) and now the manager is gone, the bottom has fallen out on the Cubs. The four year run included two playoff trips from two very good teams that couldn’t break through the first round.

2. Lou as a person has been fascinating to watch. He clearly has a wealth of baseball knowledge yet at the same time can often seem like another grumpy old man. He has one of the slowest walks to the mound. He can be grumpy with post-game questions. I have seen some pictures and I have read his statistics at but I still have a hard time believing he was a serviceable player for some good late 1970s New York Yankees teams.

3. I don’t know what to make of Pinella’s managerial skills. While he will certainly be remembered for two playoff losses (including yanking Carlos Zambrano early in Game 1 in 2007) and then asking for more left-handed hitting before 2009 (which seemed to backfire), I think managers are like the President of the United States: they get lots of credits when things are good, blamed for everything when things are bad. Ultimately, the players are the ones who make and break the team.

4. Hearing Ron Santo’s pregame interview with Pinella, I was reminded why some people don’t like listening to Santo and why some Cubs fans love him. Santo sounded depressed for much of the interview and talked about how much he enjoyed their friendship. Ron really does bleed Cubby blue.

5. I hope the Cubs go with a relative newcomer when selecting a new manager – the last two big names of Dusty Baker and Lou Pinella haven’t worked out. It looks like next year will be a rebuilding year and it would be interesting to see a younger guy (like a Ryne Sandberg?) mold a new Cubs team.

UPDATE 9:28 PM 8/22/10 – Listening to Pinella’s post-game press conference was touching as Pinella got choked up about his time in Chicago. He really did seem to enjoy his time with the Cubs – even if he may only be remembered for being another Cubs manager who couldn’t win a World Series.