Quote:
Originally Posted by jaa36
Well, it's pretty easy to say that a projection system has underrated a team AFTER the team has performed well. Of course, if you ran the Brewers' 2018 season hundreds of times, you might well have just as many times that they win 73 games as 96.
This article from by Jeff Sullivan (at Fangraphs, before he was cruelly snatched away by the Rays) looks at the projections entering 2018: https://blogs.fangraphs.com/here-is-...projections-2/. ZIPS saw them as a 79-win team; the fans saw them as an 82-win team. No one saw them as a 96-win team at the time.
This article by Sam Miller (then at Baseball Prospectus) goes into all the bizarre things that might come to pass when you simulate a season (2016) a million times: https://www.baseballprospectus.com/n...-city-1000000/
The fact that OOTP leads to results that differ from what we later see happen in real life strikes me as a feature and not a bug. It wouldn't be much fun if everything turned out the same way every time! |
First off, 79 wins is laughable when you really look at it. Milwaukee won 86 in 2017, added Cain and Yelich, and they think they'd go down to 79? With their GM hailing from an Astros franchise that led a complete rebuild to a world series? Chicago last year was probably a 90 win team, Milwaukee was probably a 86-90 win team, St Louis was probably a 85 win team. I think the problem here is these projections are based on matchups, so they say "oh, this team wont do well because they have to play this other team a lot." No, let real life and the sim engine decide that. If you project a top hitter to hit .265 because he has two teams with in his division with ace staffs, then let the sim decide that. RATINGS ARE CURRENT ABILITY, NOT STAT PREDICTORS.
Second, the randomness happens throughout the season because of non-ability factors like injuries, roster moves, etc. If you turn off injuries, turn off roster moves, and just run a 162 game season with each player playing at natural current ability level, yes i do expect it to play out similarly each time, because the law of averages says so. the sim engine itself will naturally provide some randomness to it, but common sense tells you each sim should provide a similar result most of the time.
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What ZIPS does is give projections on what will happen based on their simulations. Take Yelich, they project him at .298, but we know his ABILITY is a .300-.330 hitter. They say he ends the year under his ability because he's in a tough division which makes up the majority of his schedule.
Whats happening, is his ability is around .315, his projections are at .298, and OOTP takes the projections and says his current ability is .298.
They're basing their ratings off of simulations and then running further simulations.