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by asdfasdf32r3 3340 days ago
"In particular, the value of a batter with particular stats is dependent on the batters that come before and after him. This is the reasoning behind stacking people with high on base percentages in front of sluggers."

This is the older, common wisdom that has essentially been refuted by modern analytics (SABRmetrics, if you will).

Team-dependent statistics like R + RBI (and pitcher ERA!) are dependent on the performance of the rest of the team. They also correlate much less with a team winning games than other stats, like OBP.

That's one of the central theses of Moneyball and the SABR movement: it's better to ignore stats like (pitcher) Wins, RBI, and R, because they measure the teammates contribution more than the player you're tryign to measure.

One popular advanced pitching statistic is literally named Fielding Independent Pitching, and is calculated using only BB, K, and HR. This tracks more with contributions to a team winning than stats that include fielding skill, randomness, sequencing, etc.

What you described for a good hit / bad field team does work around the edges, but these effects are not very strong. The latest research suggests the biggest impact might be matching your pitching staff tendencies with fielders; if you have a flyball heavy staff, invest in better OF defense (Mariners, 2017). If you have worm burners (Houston, esp w/ Keuchel), invest in your IF defense.

The goal of the modern stat movement is to evaluate a player independent of team context using statistics that do not depend on their teammates. This is because estimating a players "true talent level" is much more useful than evaluating RBI.

1 comments

It seems like we're more or less in agreement...Team performance and individual performance are interdependent, particularly in naive statistics like the ones you've mentioned are traditionally used. You're talking about making team-independent estimations of player value. That's completely valid. What I'm also saying is that in a similar vein, when you are considering how a player's addition will impact a team, you need to correct for his interaction with the team as well.
Yes, agreement! Thank you for nudging me to recognize that.

However, the studies I've seen (regular Fangraphs and BP reader) suggest these interactions between player skill sets is minimal, if such an effect can be shown.

Take lineup position. It's been studied ad nauseam, by some of the brightest in the field. Turns out, lineup order, over the course of a season, doesn't really matter that much. An intentionally suboptimal lineup underperforms an "optimized" one by maybe a couple wins per year. Almost all lineups actually implemented are more like fractions of a win, which is generally within error bars.

By and large, baseball is a game where you just assemble the best talent and they will win. (This is in regard to on field talent; I do not believe "clubhouse culture fit" is as silly as in the tech world, and is usually retroactively defined.)