28 March 2019

Projections and Seeding *Update* for the 2019 Major League Baseball Regular Season

So, it turns out that, while I was posting my projections for 2019, which are based on Fangraphs' WAR, Fangraphs was updating their WAR formula to include pitcher framing. They announced their new formula the day after I posted my projections, instantly rendering them obsolete (which is, if I'm being perfectly candid, really quite rude).

Below are the updated numbers, which shift about two wins in either direction from the original, not taking into consideration the two games played in Japan between Oakland and Seattle. If you want to readjust for the opening series in Tokyo, just steal two wins from Oakland and give them to Seattle.




Had I started out with these numbers, the projected league results would have been as follows:

  • American League
    1. Houston Astros (97 - 65)
    2. New York Yankees (97 - 65)
    3. Cleveland Indians (89 - 73)
    4. Boston Red Sox (91 - 71; 1st Wild Card)
    5. Tampa Bay Rays (83 - 79; 2nd Wild Card)
    6. Los Angeles Angels and Minnesota Twins (82 - 82; 1st Out)
  • National League
    1. New York Mets (87 - 75)
    2. Milwaukee Brewers (87 - 75)
    3. Los Angeles Dodgers (87 - 75)
    4. Philadelphia Phillies or Atlanta Braves (86 - 76; 1st WC)
    5. Atlanta Braves or Washington Nationals (86 - 76; 2nd WC)
    6. St. Louis Cardinals (84 - 78; 1st out)

That's right, I just projected that the New York Mets would win top seed in the National League. You're probably thinking that there's something wrong with my model. I'd say, yeah, you're probably right, but I don't have time to look for whatever it is.

Indeed, I project the Mets to be among the biggest climbers this year, with a regular season record that ties for fifth in the majors. I expect the Phillies, Cincinnati Reds and Kansas City Royals to be much improved as well, though I don't expect the last of those teams to compete for the postseason.




On the flip side, the Cubs, Seattle Mariners and Oakland Athletics are three teams I expect to tumble this season. Both the Mariners and A's outperformed my model's expectations last year, and so my model expects these teams to return to Earth, likely burning up on reentry. The Cubs performed about as well as I expected last season, but they are aging, and the WARcels system penalizes 35-year-old pitchers harshly.




And that's it for now. You can expect more regular updates to RPScores and projections later this spring. Until then, let's enjoy the game for what it is. Play ball!

19 March 2019

Seeding and Projections for the 2019 Major League Baseball Regular Season


Baseball starts tonight in Tokyo! This is what you can reasonably expect from your teams in the upcoming 2019 MLB regular season.

Spoiler alert: fans of the Houston Astros, New York Yankees and Boston Red Sox can still expect their teams to dominate the AL, and the Dodgers should be good once again. Atlanta, Philadelphia, Washington and the New York Mets all project to finish within a game of one another. Baltimore will be bad (again).



Team depth is calculated using Tom Tango's WARcel method based on Fangraphs' WAR (see last year's projections for an explanation of how I employed that method to seed my numbers). Depth informs the Elo score I will assign to (seed) teams at the start of the season for that portion of their RPScore. Median W and Median W/G (expected record) are the numbers you're looking for regarding team projections. These numbers come with an 80% margin of error of +/- 12.2 games, and a 50% margin of error of +/- 6.5 games.



Speaking of last year's projections, how'd we do? Better than expected, actually. Initially I estimated an 80% margin of error of +/- 14 games. Turns out that was conservative: the 80th percentile adjusted* root square error turned out to be about 11.1, meaning that I could have claimed a +/- 11.1 margin of error and gotten away with it. I'll be sticking with my current Monte Carlo estimation method, tweaking it if it continues to look conservative.

*By "adjusted," I mean I'm giving myself a break for not predicting two Games 163 or that a Miami-Pittsburgh match-up would be cancelled.

Either way, only four teams finished more than 14 games better or worse than my preseason projection: Atlanta (low by 17), Tampa Bay (low by 19), Oakland (low by 24) and Baltimore (high by 30; ouch). Here's hoping for similar levels of precision in 2019.



And that's it for now. I'll return to updating my RPScores and projections sometime this Spring. See you in the sports pages!