In a departure from the past few World Series, this year’s contest between the Chicago Cubs and Cleveland Indians contains two teams that were both: a) highly regarded before the season began and b) played well for most of the year.1 (No flukes here!) The average of the teams’ pre-Series Elo ratings — a measure of a team’s strength at any given time2 — ranks ninth among the 22 World Series matchups since the wild card era began in 1995 and 37th out of the 91 since the current 2-3-2 best-of-seven World Series format was adopted in 1925.3 In other words, it’s a solid matchup.
And how about competitiveness? For each World Series since 1925, I plugged the teams’ pre-Series Elo ratings into a best-of-seven probability formula and calculated each club’s odds of winning the Series. Chicago’s win probability of 60.3 percent in FiveThirtyEight’s basic Elo model4 is larger than the average for favorites since 1925 (59.5 percent) and for favorites since 1995 (57.8 percent). So this series is more lopsided than the typical championship matchup — as you might expect when one of the top couple dozen teams of all time is involved.
All told, though, 2016 is a pretty middle-of-the-pack World Series. Literally so, if we plot out the two metrics mentioned above for every matchup since 1925:
But take heart, Indians fans — World Series upsets appear to happen more frequently than basic Elo would predict. Based on the pre-Series probabilities I crunched, the favorite would have been expected to win the World Series 54 times in 90 tries since 1925, for a predicted winning percentage of 60 percent. In reality, however, favorites won only 49 times over that span, for a success rate of 54 percent. Whether that’s because basic Elo can’t pick up on the differences between regular-season and playoff baseball,5 I’m not certain. But it is a sign that the Series might be more competitive than Chicago’s 60.3 percent win probability indicates.
That’s bad news for anxious Cubs fans hoping to end a 108-year championship drought. But it’s good for Cleveland, as well as agnostic observers (such as myself) who want the baseball season to last as long as it can.