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by conjecTech 3341 days ago
The entire offensive side of the game pretty clearly violates the notion of independence. 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. If it were not a team sport, you'd see no clear patterns in line-up. This applies at the team selection level as well. For instance, a player who can draw a lot of walks is worth different amounts to different teams depending on their ability to convert those into runs.

The fact that saving a run is nearly equivalent to scoring a run means it bleeds over into the defensive side as well. A phenomenal batter with a high error rate may be of enormous value to one team since their pitching staff strikes out more batters than average while being a terrible addition to another team.

If you're still unconvinced, I could throw together some simulations later that might make this clearer.

3 comments

"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.

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.)

This kind of reasoning go only so far. While you are technically correct, the difference that something like batting order makes is marginal in the long run. The advantage of a fully optimized vs. a totally random batting order would equate to approximately 1-2 additional win(s) over the span of a full 162 game season.

That being said... one win can be the difference between a playoff spot or not, so it clearly does matter. I'm just trying to emphasize that the teamwork aspect of the offense is minimal, as a lineup of hitters with solid statistics is more important than the order in which they bat.

However, the defensive side of things is much more tricky to measure. Baseball statistics still have a difficult time calculating the value (for better or worse) of a player's defense and nobody is arguing that it doesn't significantly affect a team's performance.

That's fair enough. Although I'd argue that it's more a case of assembling an appropriate portfolio than it is a "team" in the way that people normally use that term.

(I'd also argue that overall offensive ability trumps a lot of optimization around base stealing or the type of hits.)

ADDED: i.e. I'd argue that if populating a roster with about a half dozen All Star sluggers were financially viable, I'd argue that would probably be a pretty effective team however unbalanced.

As covered in Moneyball (the book), the "sluggers" tend to swing at more. So although they may hit home runs, they also tend to strike out a lot too.

The actual approach was to get a bunch of people who worked to extend the inning by not getting out.. aka getting on base safely. You don't need many big hits when you can get singles and doubles consistently.

A couple years ago, I met a small scale angel investment group that complained "we haven't had a unicorn" but when we chatted more, I found out 60% of their investments were acquired in under five years with them making ~5x each time.

Not as sexy but sounds like a good strategy to me.