The Philadelphia Eagles are off to a flying start under the helm of first-year head coach Doug Pederson and rookie quarterback Carson Wentz. The 3-0 Eagles are far surpassing expectations, as many considered this season to be one of rebuilding (sound familiar, Philly fans?). After the Eagles’ recent 3-34 throbbing of the Pittsburgh Steelers, fans are getting pumped about their team’s surprising success. But are the Eagles really that good? There are a number of ways to measure a team’s success. In this article, we will focus on Plus/Minus.
A common statistic to measure a team’s success is plus/minus (referred to as
+/- from here on).
+/- is the difference between the number of points a team has scored and the number of points their opponent has scored (also called a point differential). For example, the Eagles’
+/- vs. the Steelers was 31 (
+/- can be a useful statistic to measure success because it shows how much a team is winning by, rather than record which only shows whether or not they won. A team could win a game, but winning that game by 1 point shows the team played slightly better than their opponent while winning that game by 33 points shows dominance. It’s important to note that
+/- is far from a perfect measurement of a team’s success. A team could get lucky and play many bad teams, boosting their
+/-. However, it can still be a useful statistic.
Since we’re only three weeks into the season, and the Eagles had a bye week 3, we will only include data for the first three weeks of every season. Here is the historically best
+/- for every NFL season since 1978 (data from before these seasons was not available in the dataset we used):
The Eagles’ current
+/- of 65 through week 3 is the by far the best of 2016; second is the New England Patriots with 36 points. The historically average best
+/- through week 3 is ≈ 57.36, so the Eagles are above the historically average best
+/- at this point in the season. As seen in the graph, however, the Eagles are far from the best team ever. Ten teams have had a higher
+/- (one of which was the 1980 Eagles which had a
+/- of 88 — that team would go on to lose in the Super Bowl vs. the Oakland Raiders); the 2003 Denver Broncos also had a
+/- of 65 through week 3.
Here is the Eagles’
+/- through week 3 for every season since 1978:
The Eagles’ average
+/- is ≈ 9.72, which is better than the league average (the average
+/- must be 0). The only season in Eagles history that’s
+/- through week 3 is higher than their current of 65 is 1980, as mentioned above.
+/- isn’t a perfect way of measuring a team’s success, it can be useful to see how a team is doing. The data appears to show that the Eagles are a very good team with a strong start, but certainly not the best ever. We will just have to wait and see if the Eagles can continue to build on their momentum in the coming weeks, especially considering they had a bye this past week. This data is far from conclusive that the Eagles will continue to be a good team.
Data for NFL games from 1978->2014 obtained from nfl_results by devstopfix on GitHub. Games for first three weeks of 2015 & 2016 seasons obtained manually by Statistica. Data is not guaranteed to be correct.