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Jun 16

The Mathletics Behind Playoff Upsets, Part 1

NBA = No Upset Association?
The NBA in large part became what it did today through dominance, whether by a franchise or player. No wonder players like Michael Jordan and Magic Johnson transcended the sports world during their time as players. They won in bunches, and they did so in a sport where a single player has the most individual value (something we’ll discuss at a later date). Most importantly, they won in bunches, and the league thrived off those big names because they so commonly won championships (Johnson with five, Jordan with six).

Perhaps that’s not possible without the top seeds dominating postseason play. The championship disparity between the top three seeds and the bottom five seeds is absolutely staggering.

Table 3: NBA Championships by Seed

Years 1 2 3 4 5 6 7 8
1984-2015 21 6 4 0 0 1 0 0
1971-1983 10 1 2 0 0 0
1947-1970 15 8 0 1
Total 46 15 6 1 0 1 0 0
Percent 66.7 21.7 8.7 1.4 0 1.4 0 0

Table 4: Conference Championships by Seed

Years 1 2 3 4 5 6 7 8
1984-2015 35 18 7 2 0 1 0 1
1971-1983 14 4 6 1 0 1
Total 49 22 13 3 0 2 0 1
Percent 54.4 24.4 14.4 3.3 0 2.2 0 1.1

PLAYOFF EXPANSION NOTES: League expanded the playoffs to 16 teams in 1984. League expanded from divisions to conferences in the 1970-71 season. The NBA (then BAA) began play in the 1946-47 season.
PLAYOFF SEEDING NOTES: In 1950, seeding in table went according to final round, not divisional rounds. In 1971 and 1972, seeding in table was converted from divisional seeds to conference seeds for a relevant comparison.

The dominance of the NBA’s top seeds speaks for itself. The league’s one seeds won more than half of the total NBA Championships. Furthermore, it’s happened at this rate in each era in league history. Each of the top three seeds owns more league championships than the rest of the lower seeds combined (46 to 23 for one seeds, 15 to 8 for two seeds, 6 to 2 for three seeds). Meanwhile, the bottom five seeds own only six conference and two league championships in league history.

The exceptions are as followed:

  • 2009-10 Boston Celtics (50-32): Eastern Conference four seed, Lost NBA Finals (played Lakers for 12th time in NBA Finals)
  • 2005-06 Dallas Mavericks (60-22): Western Conference four seed, Lost NBA Finals (third-best record in NBA)
  • 1998-99 New York Knicks (27-23): Eastern Conference eight seed, Lost NBA Finals (strike-shortened season)
  • 1994-95 Houston Rockets (47-35): Western Conference six seed, Won NBA Finals (acquired Clyde Drexler in February)
  • 1980-81 Houston Rockets (40-42): Western Conference six seed, Lost NBA Finals (second team with losing record)
  • 1977-78 Seattle SuperSonics (47-35): Western Conference four seed, Lost NBA Finals (started 5-17, last road G7 win)

Also, the following is an exception…

  • 1968-69 Boston Celtics (48-34): Eastern Division four seed, Won NBA Finals (11th championship in 13 years)

Of course, that’s not much at all. Just look at the overall consistency of higher seeds winning series since the league expanded to a 16-team playoff system in the 1983-84 season.

Record for Higher Playoff Seed, by Year since 1984 (excluding NBA Finals)
2015: 11-3, 2014: 10-4, 2013: 9-5, 2012: 11-3, 2011: 10-4, 2010: 10-4, 2009: 10-4, 2008: 13-1, 2007: 9-5,
2006: 10-4, 2005: 10-4, 2004: 11-3, 2003: 10-4, 2002: 11-3, 2001: 10-4, 2000: 10-4, 1999: 10-4, 1998: 11-3,
1997: 13-1, 1996: 10-4, 1995: 9-5, 1994: 10-4, 1993: 10-4, 1992: 12-2, 1991: 9-5, 1990: 10-4, 1989: 10-4,
1988: 11-3, 1987: 9-5, 1986: 13-1, 1985: 11-3, 1984: 10-4, Total: 333-115 (74.33 win percentage)

The 2014 NBA playoffs had its moments of near-upsets in the first round, with five Game 7 battles. However, the lower seed won only one battle. It the end, the year’s postseason put together another summer of favorites advancing deep into the postseason. With the worst record in this study being 9-5, it shows that the NBA is seriously lacking an element of unpredictably.

To further bring home the point, in NBA history, only five teams with the eight seed upset their top-seeded foe in the first round. That’s out of 64 such battles, giving an 7.81 winning percentage in the first round.

NBA Playoff Upsets, 8 over 1 (1984-2015)
2012: Philadelphia over Chicago (4-2)
2011: Memphis over San Antonio (4-2)
2007: Golden State over Dallas (4-2)
1999: New York over Miami (3-2)
1994: Denver over Seattle (3-2)

Just to make a comparison, in the NCAA Division I Men’s Basketball Tournament, the one seeds are 51-12 against eight seeds since tournament expansion in 1985. Therefore, eight seeds own a 19.05 win percentage in such games. Sure, it might not be a fair comparison, considering that the NCAA Tournament has a one-and-done format. Still, the difference in upset between the two levels is palpable, and it’ll be a factor for discussion in part two of this study.

Sadly, the same happens when the history of the seventh seed comes into account. There are only five such upsets over a 31-year span. Strangely, the 7 over 2 upsets have thus far occurred less frequently than the 8 over 1 upsets since the league changed the first round to a Best-of-7 format in 2003. However, during the Best-of-5 era, we saw some quick upsets.

NBA Playoff Upsets, 7 over 2 (1984-2015)
2010: San Antonio over Dallas (4-2)
1998: New York over Miami (3-2)
1991: Golden State over San Antonio (3-1)
1989: Golden State over Utah (3-0)
1987: Seattle over Dallas (3-1)

Again, by using the NCAA Division I men’s basketball tournament for comparison, the two seeds are 53-20 against seven seeds since 1985. Therefore, the seven seeds have a 27.40 win percentage in such games. That’s nearly four times the winning percentage of the seven seeds in the NBA playoffs! The difference here is quite remarkable.

Upsets seem to have no place in the NBA playoffs, something which no longer holds true in the NFL playoffs after recent seasons.

1 ping

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