AL Update: 13 Weeks In

How well did the game lines from April and May (that's simplifying it, but those are basically the time frames) predict those in June (through 6/28)? Pretty closely:

I can't think of any reason for the April lines to be weighted more heavily than the May odds; that's probably just a fluky thing. Combined, the lines from the first two months explain about 57% of the variance in the June lines, and there's not a whole lot of regression towards PECOTA/CHONE; in fact, the two weights add up to over one (1.05). For this post, I weighted the months as follows: 40% June, 30% May, 20% April.

RS/G, RA/G: Through games of Sunday, 7/5.
Current: Current team strength in wins per 162 games against an average schedule.
Current Div%: Current percentage chance of winning division, as of 7am EST on 7/6.
Prev Div%: Percentage chance of winning division as of six weeks ago.
Diff: Subtraction.
Div: Best odds available on team to win division.
Site: Where those odds can be found (BetUS, SportsBetting, Bookmaker)

The division from hell. I have the ALE winner averaging 98.5 wins, which isn't that impressive until you consider strength of schedule. Even more telling is that the third place team comes in at 87.2 Ws, right up there with first place in the Central (87.8) and West (88.7). It's entirely possible that the Rays will have the best third-order record in baseball, and finish third in the East. In the simulation the WC winner came from the East an impressive 96.5% of the team. At this point it seems like the playoffs will consist of two ALE teams, the Dodgers, and five overwhelmingly mediocre squads.

Why do the game lines have the Yanks so far ahead of Boston? Let's find out:

n: Number of starts.

W%: Average implied team W% in those starts, according to game lines.

OU: Average over/under for the game in those starts

RS: Pythag expectation for team RS in those games, taken from previous two columns

RA: Pythag expectation for team RA in those games, taken from previous two columns

This doesn't adjust for strength of schedule or park factors, although the former should come close to evening out for the guys who have been making regular starts, and I wouldn't even know how to adjust for the latter, since the Yankees have only played 42 games in the new park.

Sabathia helps, but unless you throw some crazy NYS park factors into the mix -- and it's not like Fenway is a pitchers' haven -- it's New York's offense that's made the difference. Back in reality, the Yankees had scored 24 more runs than Boston coming in to Monday. But, contrary to what the lines had expected, the Red Sox have allowed 39 fewer runs than the Yankees. Part of that can be "blamed" on NY allowing 37 runs in Wang's second and third starts of the year, but certainly not all, as the Red Sox have had some ugly games themselves.

The Twins are definitely interesting, with the best run differential (+33) and best third-order record (45-38) in the division, to go along with the strongest club according to the game lines. Detroit's 4.8 R/G is respectable, but most of that has been good timing: their AEQR is 20 runs fewer than that, and their team OPS+ is just 93. Throw in some regression from Jackso, Porcello (who's being skipped in the rotation to keep his innings down), and Rodney's save percentage and it's easy to see the Tigers falling off a bit in the second half.

Toronto may have a stretch in August or September that's tougher, but, as pointed out by USSM, this has to be close to the most difficult nine game road trip of the year:

The odds expected the Mariners to go 3.3-5.7 over those games, a .369 W%. As you can see, Seattle actually won five of nine, keeping them right in the mix in the West. Going 5-4 may not seem all that impressive, but if you keep every other team's results constant those nine games boosted their ALW odds significantly, from 11.4% to the 15.3% seen above.