A lot has been said about the Chicago Cubs poor record on the road. Since it contrasts so starkly against their sterling home record, the dissonance is mind-numbing.
So are the Chicago Cubs as bad on the road as their record suggests, or is it something else? Could it just be bad luck? Sabermetricians measure a team’s performance a lot of ways, but the run differential is almost the Holy Grail of metrics. Nothing aggregates more effectively and accurately the performance of a team than run differential.
The Cubs run differential after Thursday’s game is 628 runs scored vs. 554 runs allowed for a plus 74 run differential. And that equates to a Pythagorean Win-Loss of 70-56. As of Thursday, they are 69-56, so right on the mark.
But wait, Pythagorean what? Hold on my fellow math impaired fans; it’s not that hard.
Bill James did this to us. He took our beautiful back of the baseball card world and filled it with a bunch of math. Fortunately, the math is done for us thanks to the wonders of technology. Analytics allows us to learn more about the game we love. As Mickey Mantle once said, “It’s unbelievable how much you don’t know about the game you’ve been playing all your life.”
So what is Pythagorean win-loss? It takes run differential and computes what a team’s actual win-loss record should be. It can also project what a team’s performance will be, and it is very accurate. Yes, you can go to Vegas on this one. What you do there is your own business, of course.
Teams very rarely exceed their Pythagorean win-loss by very much, or for very long. Look at the Pirates, who at the end of May were .500 and in third place, three games out of first. Their run differential was negative 64 for a Pythagorean win-loss of 22-34.
Their run differential worsened as the season went on, and now, quite predictably, they are in last place, at 52-74. Which is precisely where their Pythagorean win-loss said they would be in May.
The Cubs on the road
The Cubs have a run differential on the road of negative five. We plug their runs scored vs. runs allowed in road games into the Pythagorean computer, and we get a road record that should be .500, 32-32. Their road record is 25-36 for a .398 winning percentage.
That’s right, aggregate all that road performance, the good, the bad, and the ugly, a lot of ugly, into two numbers, runs scored vs. runs allowed and, what is happening?
It’s bad luck, very bad luck
The Cubs are 19-20 in one-run games. Their run differential in those games? Minus one run. Funny how this works out, right?
But, this is where it gets weird. 14 of the 20 one-run loses, or 70 percent, are on the road. Even more startling is that seven of the 14 one-run losses on the road were due to walk-off hits. That’s being unlucky. This isn’t Vegas lousy luck either. This is statistical bad luck, and that’s why it’s not sustainable. Statistics don’t like luck, good or bad.
What about the home differential and record? Aren’t they getting lucky at home? The Cubs home record of 44-19 is over their Pythagorean win-loss of 39-23, but not anywhere near the discrepancy that afflicts their road record. I am confident that they can sustain that rate of winning at home.
Seventeen road games
The Cubs have 17 road games remaining. If the Pythagorean win-loss model holds, and it seldom fails, the Chicago Cubs should win half of those games if their runs scored vs. runs allowed stays precisely the same as it has been all season.
But I believe their road run differential will improve. So with the Cardinals spot on where their Pythagorean says they should be, and the Brewers overperforming theirs, if that happens then the division, statistically speaking anyway, belongs to the Chicago Cubs. You can go to Vegas on that.