With 16 Games to Go, the AL West is Mostly--But Not Fully--Secure
In the playoff odds, the 3 game losing streak didn't change the AL West odds that much. But I sure felt better after the Astros won and the Mariners lost on Thursday.
It was of course just one game, but yesterday’s win over the A’s felt a little bigger than most this season. Most of that was psychological though.
It felt bad that the Astros had lost 3 straight games and particularly bad to lose a pair of one run games to a team with less talent than the Astros. And it felt particularly bad in the top of the eight inning when Brent Rooker hit a game tying home run off of Ryan Pressly.
So my psychology was improved when the Astros struck back in the bottom of the eighth as four straight batters reached with two outs to produce 4 runs and a victory. I bet your psychology felt better too.
And then my psychology improved when I woke up this morning and learned about another eighth inning. In Seattle, the Rangers put up a 3 spot in the top of the eighth to take the lead over the Mariners. Unlike the Astros, the Mariners did not respond by scoring runs, and they fell 4.5 games back in the AL West.
Psychological Nagging
I say most of the good feeling about yesterday’s win was psychological because its effect on the final standings in the AL West is not likely to be big at the end of the season.. The Astros entered yesterday in a controlling position in the division, despite the Ms having cut their deficit to 3.5 games.
Yesterday morning, the Fangraphs playoffs odds had the Astros with a 94.7% chance of winning the division. Play the rest of the season 20 times, and the Astros would win the division in 19 of them.
But the 94.7% number drew my attention because it was just slightly less than 95%. In my real job, I am a professor of political science. It is generally accepted in academic writing that one can say that something “will” happen if you can statistically prove it has a 95% chance of happening. 94.7% isn’t good enough.
The Mariners Are Unlikely To Get Hot Enough to Win the Division
That psychological nagging—the sense of dread the 3 games losing streak produced—has some academic validity to it. The division is mostly—but not fully secure.
How secure is is? And how much work is “mostly” doing?.
After games yesterday, the Astros have 16 games remaining this season, starting with a 3 game tilt in Anaheim. The Mariners have one fewer game remaining. The table below shows different records for the Astros on the left, and the record the Mariners much achieve to tie the Astros in the standings.1
The Astros are a slightly above .500 team. Let’s say the Astros go .500 the rest of the season, then the Mariners would need to win 12 of their remaining 15 games. Are the Mariners capable of doing that? Sure, I guess any team is. Are Mariners likely to do that? No; this season, their largest number of wins in a 15 game span is 11, and they have not done that since early June.
Of course, the table also shows you that if the Astros go below .500, then the number of games the Mariners have to win to tie the Astros goes from the seemingly impossible to just unlikely. The Astros do not have to go on a hot streak to win the division, but they do have to keep winning some games.
They are of course likely to do so. The figure below goes up when a team wins and down when they lose. You can see in the orange line that the Astros lost a lot early in the season (sorry to bring that up again). But since then, the Astros have moved upward over time. You can see their winning streak in mid-May that brought them back to respectability, and the long winning stretch over July and early August that put the Astros in control of the division.
Wwhat stands out on the chart right now to me are the other two periods of the post-nadir part of the season. The Astros remained essentially even over the month of June and since taking the six game lead in the division in late August.
If we treat the opening 26 games of the season as an aberration, the Astros are quite unlikely to have a bad enough record over the last 16 games that the Mariners could match them without going on a huge hot stretch of their own.
Don’t Worry About Saber-Tooth Tigers
Put these two together—the unlikelihood that the Mariners go on a huge winning stretch and the likelihood that the Astros go around .500 at best—and you can see why the computer models give the Astros such a good chance of winning the division.
In fact, after yesterday’s game, Fangraphs now has the Astros chances of winning the division up to 96.3%. The Pecota model at Baseball Prospectus is slightly more optimistic—they rate the Astros chances of winning the AL West at 97.0%.
I have sketched out the logic here for why those odds are so favorable to the Astros. Does that take away the psychological anxiety you feel about the the last part of the season? Well, I can’t change your feelings. But I know this, our psychology is highly attuned to potential dangers. It’s how our ancestors avoided being eaten by saber-tooth tigers.
But in the modern world, we don’t have to worry about saber-tooth tigers. We do have to worry about the Mariners going on a big hot stretch. But the numbers show we only need to worry about that just a tiny bit.
I find that reassuring. That may not work for you.
The Mariners would likely win the AL West tiebreaker. The only way for the Astros to win the tiebreaker is to sweep the Mariners in their upcoming series. Of course, if they Astros do that, they almost assuredly win the division anyway.