How the Cubs Stack Up Within Baseball History

Importantly, for the Cubs, this season isn’t over. Obviously, this season isn’t over — in a sense their real season hasn’t begun. We’ve known the Cubs would make the playoffs for something like five and a half months, and only now do they get to compete for the grand prize. Because there are games remaining, this might not seem like the best time to examine the 2016 Cubs through a historical lens.

I believe the opposite, though. At last, we have final, official regular-season statistics. Those are the stats that matter the most. And even though the Cubs are clearly Team No. 1 moving forward, the odds are still better that they don’t win the World Series. They’re probably going to lose, somewhere and somehow. And I don’t want to allow for playoff emotion to color the way people feel about this analysis. This season, the Cubs won eight more games than anyone else. The Cubs had a better run differential than anyone else, by a margin of 68. Clearly, they were really good. But how good, historically, when you’re talking about more than 100 years?

I’ve decided to analyze by three categories: winning percentage, run differential (per game), and OPS differential. I know it feels like only wins should matter, when the season’s complete, but you’ll never convince me that 162 games is sufficient to balance out the noise, hence the other two measures. Run differential is less noisy than win/loss record. OPS differential is less noisy still. And in order to conduct all this analysis, I went to the Baseball-Reference Play Index, which gave me information stretching back to 1913. I wound up with a sample of more than 2,200 individual team-seasons.

So to get right on with it: here are some Cubs rankings.

Out of everyone, the Cubs rank in the top three percent in winning. They rank in the top one percent in run differential, and in OPS differential. That’s why you could make the argument they were even a little unlucky. The best ranking here is OPS differential — in that specific category, the Cubs rank 12th.

I decided I wanted to go another step further. As much as I like those general statistics, an overall rank does nothing to capture performance against league spread. I feel like performance should be evaluated differently if it occurred in a season with very much or very little parity. So for every individual league-season, I calculated the standard deviation in each of the three stats. Then, for every team in every season, I calculated z-scores for each of the three stats. A z-scores just measures the number of standard deviations away from the average. Here are the new Cubs rankings, including a fourth bar, which just takes the average of the three z-scores:

The Cubs manage to shine even more. By winning, they’re just out of the top 10, but they’re now fifth by run differential, and second by OPS differential. The average of the three z-scores puts them in sixth. The five teams ahead of them:

• 1984 Tigers (won World Series)
• 1986 Mets (won World Series)
• 1995 Indians (lost World Series)
• 2001 Mariners (shut up)
• 1944 Cardinals (won World Series)

There are a lot of ways to try to slice this, but you could convincingly argue this identifies the best teams ever (or at least since 1913). The Cubs would fit in pretty well with the group. This analysis loves those 1984 Tigers — they finished with eight more wins than anyone else, and across the three stats, they were an average of 2.63 standard deviations better than the mean. The Cubs show up at an average of 2.38 standard deviations better than the mean. That doesn’t make them the best team in baseball history, and I haven’t even made an attempt to adjust for the National League seemingly being worse than the American League, but the Cubs are around the best ever. They could hold their own in conversation.

One last thing. I had, for every team ever, the average of the three z-scores. So then, for every season since 1913, I figured out the difference between the average of the best team, and the average of the second-best team. Here’s what that plot looks like:

The line shoots up there to the right, to meet the outstanding nature of the 2016 Cubs. By this measure, the Cubs are the best team, and the Red Sox are the second-best team, but the difference between their averages is 0.79. That’s the biggest difference between the best and second-best teams since 1995. It’s the 11th-biggest difference overall, out of a sample of 104. What this is saying: The Cubs were almost inarguably the best baseball team of 2016. I know some people believe the playoffs manage to crown the best of the best. I get it; I treasure the playoffs, too. But the playoffs are different. They measure something else. Some might say they measure very little at all. When teams are constructed, it’s with the regular season in mind, and the Cubs just steamrolled their way through from start to finish. Every regular season has a best team, but relatively few regular seasons have a best team as dominant as this year’s best team. You could say the Cubs were the most outstanding baseball team in two decades. Even in 2001, the Mariners weren’t that much better than the A’s. The Cubs left little question which team belonged at the top.

If the Cubs lose in the playoffs, this would be of little consolation. If the Cubs win in the playoffs, this could feel of little relevance. Which is why I wanted to get this in now, before anything begins. I don’t know what’s going to happen with the Cubs in the second season. In the first one — the long one, the real one — the Cubs were far better than anybody. Maybe it’s not quite mission accomplished, but, it really kind of is.