NBA Early Season Performance (11/04/16)

By Sean Pyritz @srpyritz

As the saying goes, there is no time like the present. However, early in the NBA season there is nothing but the future. That future is still full of mystery, hardly cleared up by a week's worth of games. It is tempting for us as fans to jump to conclusions based on the present, but how much of what we've seen is real and how much is mirage? Today we will take a look back in time to guide our incorporation of the new information opening week has introduced.

At this point in the season, a little over a week in, most teams have played five games. Therefore, as a gauge for how the beginning of the season translates to the end, we will use the first five games in each of the last six seasons – the first six of the decade - and compare them to the full season results. These are arbitrary cut-offs but there is value to capture regardless. In the graph below, each of the 180 observed teams are grouped by how many of the first five games they won. Within each win group, the final win percentage distribution is shown in a box plot – the ends of which represent the range of outcomes and the middle line, where the shade changes, represents the average. The gray dots are outliers.

For example, teams that won all of their first five games to open the season finished the season with an average win percentage of around .700 (.680 to be precise). Looking at each of the boxes, we can see the average end of season winning percentage increases with each additional win to open the season - the middle line moves up the win percentage axis on each subsequent box. Over the past six seasons, the difference between winning zero and five of the first five games has been worth .400 winning percentage points by the end of the year. This is not a very strong relationship between wins at the beginning and the end, however, because the ranges of possibilities are so large.

The ranges of the full season win percentage distributions grow and then drop again with each additional early season victory. The largest range is for teams that went 2-3 to open the season - the 2011 Bulls finished with a .756 win percentage while the 2014 Bucks finished with a .183 win percentage. On the other end, teams that opened 5-0 had the smallest range of outcomes. We do see a few outliers with the 5-0 teams, most recently the Warriors of 2015 and 2016 – the two dots at the top right of the chart above the box plot. As you would expect, a small range of outcomes means a reduced amount of uncertainty. All 12 teams that have opened the season 5-0 since 2011 have made the playoffs. Correspondingly, none of the 11 teams that started 0-5 have made the playoffs. In between, from one win to four wins to start, the percentages of teams that have played in the postseason are 14%, 45%, 69%, and 79%, respectively.

No matter how scant 180 team seasons worth of data may be, there is evidence here of the power of the early season. It may be obvious that the best teams in the league would perform well all season including the beginning, but it is fascinating how a rough start after just five games could be a death sentence for a playoff opportunity. There is nothing especially substantial here, especially for the majority of teams that finish 3-2 or 2-3 after five games, but it is worth examining the teams falling on the edges after five games this season and calibrate future expectations accordingly.

Philadelphia 76ers (0-4) – with the Cavaliers on tap for game number five, chances are pretty good the 76ers will begin the year 0-5 and put the finishing touches on another year in the lottery – as expected to start the year. They've been awfully competitive early on but are still plagued by the self-inflicted talent issues as they grow with their young players.

Washington Wizards (0-3) – as the only team to have played only three games, the Wizards still have two opportunities to avoid the 0-5 tombstone. Mocked in the media, Wizards center Marcin Gortat may not have been so far off to suggest the Wizards home opener against Toronto was a must-win. Atlanta and Orlando round out their first five matchups. While Washington hasn't been uncompetitive to this point, their defense is dead last in the league. Hope is not lost for Wizards fans though; John Wall is off to a strong start (save the turnovers), they are allowing a very unlucky and unsustainable 45% from three-point range, and they have a somewhat favorable schedule the rest of the way. Hopefully this team isn't forced to test the 0-5 lottery streak, as many people had high hopes the Wizards would return to the playoffs coming into the season.

Cleveland Cavaliers (5-0) – with their win over a hobbled Boston team Thursday night, the Cavaliers secured their spot in the playoffs. Off to the best start for any LeBron-led team, the prohibitive preseason favorites in the East, and the reigning NBA Champions, this Cavaliers team is highly unlikely to break the playoff streak for 5-0 teams. Such an incredible start shifts the focus from best record in the East to best record in the league and home court advantage in a potential third consecutive NBA Finals appearance. I read some people (aka me) predicting Toronto would snatch the East from a coasting Cavaliers squad – a gross miscalculation it appears.