How Likely was it for Boston to Win Nine Championships in Thirteen Years?

By Derrick Yam '17 parades

Coming off of the most recent Super Bowl victory for the New England Patriots, Boston fans took full advantage of the opportunity to boast about their incredibly successful sports teams. But is it really that impressive for Boston to win nine combined championships among the Red Sox, Patriots, Celtics, and Bruins over 13 years? In MA204 with the great Professor Dr. Michael Lopez, we used the computer software “R” to find out. In order to conduct this simulation, we had to make certain assumptions. It is essential that we inferred that each team, out of the 30 teams in the NBA, MLB, and NHL, as well as the 32 teams in the NFL, had an equally likely chance of winning. There are numerous variables that people want to attribute to winning percentage, such as payroll, and the previous year’s performance. Nevertheless, a scatterplot of payroll and winning percentage presents convoluted and indefinite results. To the right is an example of the correlation between money spent and wins in the MLB in 2009. Photo by quora.com Although the least squares regression line displays a positive correlation, the regression coefficient which proves the strength of the relationship is very weak—in fact, the value was less than .4 (For those of you who are not familiar with statistics, a regression coefficient value of 1 indicates a perfect relationship, and a value of 0 indicates no relationship at all). Similarly, accounting for the previous year’s performance offers just as inconclusive tendencies. For instance, following the Red Sox World Series Championship in 2013, the team pulled off a .438 win percentage in 2014 and did not make the playoffs. Following this analysis of variables and deciding on an equal chance of winning for all teams within each league, we ran the simulation. In “R,” we ran 100,000 trials of 13 years, with the probability of each Boston team winning a championship for each of those 13 years, to be 1 in 30 for the Red Sox, Bruins, and Celtics, and 1 in 32 for the Patriots. Our results proved that Boston is truly a professional sports powerhouse (no bias at all, as I am a resident of Massachusetts). Our simulation gave us an average number of championships within those 13 years to be only 1.70271, and the probability of winning 9 championships to be 4 out of 100,000—or .00004%. The simulation did not give any possibility for winning nine championships in 13 years. What this proves is that Boston truly did accomplish an incredibly challenging feat. Now, further studies can be made accounting for certain underlying variables, or considering that there are only twelve cities in the United States with four professional sports teams. However, this does not diminish the task that Boston has completed. Boston has the best sports team in the world, and I am 100% not partial to the tremendous state of Massachusetts.