Amuseddaysleeper
06-02-2014, 01:31 PM
All signs point to a Spurs title
Analyzing three decades' worth of Finals trends to anticipate winner
Regression analysis shows one team is significantly favored heading into the NBA Finals.
The Miami Heat and San Antonio Spurs have reached the NBA Finals, setting up a rematch of last year's classic seven-game battle. With four days between the conclusion of the conference finals and Game 1, now comes the real fun: predicting the outcome.
Predicting the NBA Finals is somewhat different from other playoff series. First, there's more playoff data available -- three full rounds against a variety of opponents, giving a better idea of who's playing better right now. Second, because the teams have played each other just twice during the regular season, there's less head-to-head data to determine whether the matchup is good or bad.
So what has really mattered when picking the winner of past Finals? And what does that say about this year's series? Let's take a look.
Matters: Regular-Season Records
Ordinarily, statistical projections will start with point differential. But when it comes to the NBA Finals, during the past three decades, records have matched up better with results than differential.
When the two teams were separated by three games or fewer during the regular season, teams with home-court advantage have actually been more likely to get upset than win the series, going 4-5. But when they won at least six more games during the regular season, they've gone a dominant 16-2, with 1995 (Houston over Orlando) and 2006 (Miami over Dallas) the lone exceptions. That's bad news for the Heat, who finished eight games behind the Spurs in the standings.
Doesn't Matter: Head-to-Head Results
Against conference foes, there is predictive value to the regular-season series between the two teams -- especially in the opening round. That doesn't carry over to the NBA Finals. Two games simply aren't enough to tell us much about how the teams match up.
Half of the past 30 Finalists have split the season series, as Miami and San Antonio did this season. Though nine of the other 15 Finals were won by the team that swept the season series, that doesn't provide much new information because most of those teams had home-court advantage. The lower-seeded team has gone on to win the Finals just once out of the four times it swept in the regular season.
Matters: Playoff Performance
It pays to be hot going into the Finals. When the lower-seeded team had a better point differential during the first three rounds of the playoffs, adjusted for schedule, the series is nearly a toss-up -- the favorites win 57.1 percent of the time (8-6). When the team with home court also has performed better during the playoffs, however, they're a dominant 14-2 (87.5 percent), with 1998 (Chicago over Utah, when the two teams were nearly even leading up to the Finals) and 2006 (Miami over Dallas, again) the exceptions.
The Heat (plus-7.0) and Spurs (plus-8.0) had similar average margins en route to the Finals. However, San Antonio played a much more difficult schedule in the competitive West. So San Antonio's adjusted differential of plus-11.6 points per game is much better than Miami's plus-8.1 mark.
Doesn't Matter: Games Played
Because the Spurs went a full seven games in the first round, the Heat have played three fewer games in the postseason. Turns out that extra rest is not a factor in why playoff performance to date matters in the Finals. In fact, favorites who have played more games (like San Antonio) have actually tended to perform slightly better than expected, possibly because it means they've faced more challenging opposition.
Matters: Defensive Rating
Yes, defense wins championships -- as long as it is paired with a good-enough offense to get to the Finals. The team with the better defensive rating during the regular season has won 19 out of the past 30 Finals, a figure that substantially understates its importance. See, offense-first teams are more likely to have home court in the Finals. When the better defensive team also has home-court advantage, it has won 86.7 percent of the time (13-2). And better defensive teams have frequently pulled upsets without home court, going 6-9 (40 percent) in those series.
Again, the importance of defense favors the Spurs. They were the better defense in the regular season, ranking fourth in points allowed per 100 possessions; Miami finished 11th. The Heat would be the first team to win the championship while finishing outside the league's top 10 defenses since the 2001 Lakers (21st).
Unlike those Lakers, Miami hasn't yet shown the ability to turn on its defense for extended stretches during the playoffs. The Heat reached the Finals largely on the strength of their offense, which dominated the league's No. 1 (Indiana) and No. 6 (Charlotte) defenses. Miami scored 12.9 more points per 100 possessions during the East playoffs than its opponents allowed during the regular season (weighted by games played), but allowed them to score 2.8 more points per 100 possessions than usual.
By contrast, San Antonio's playoff run has been incredibly balanced. In fact, the Spurs have been slightly better on defense (plus-7.4 points per 100 possessions better than opponent averages) than offense (plus-6.9). That kind of balance is rare in the postseason. Just five teams since the ABA-NBA merger have been at least six points better than average per 100 possessions at both ends of the court.
Putting it Together
A regression that combines regular-season win differential and playoff performance leading up to the Finals -- but not defensive rating, which isn't statistically significant as part of a regression -- correctly retrodicts 27 of the past 30 Finals outcomes. Based on that, San Antonio has an 88 percent chance of winning the Finals.
The good news for Miami? As you might guess from going through the indicators, the biggest upset in modern Finals history was pulled off by another Heat team with Dwyane Wade.
http://i58.tinypic.com/2yubzt1.png
Still, nine of the 10 teams most heavily favored entering the Finals won the series, and none of the underdogs even forced a Game 7. The 2006 Finals are also the exception to the rule when it comes to favorites who had a better point differential in both the regular season and the conference playoffs. Those teams are 11-1 in the past three decades.
Despite this overwhelming evidence, the Heat are only slight underdogs to win the series in Las Vegas. The most common line suggests the Spurs have a 57 percent chance to win. In part, the discrepancy can be traced to the popularity of Miami, as two-time defending champion. But it also surely reflects a belief we still haven't seen the best of the Heat, given Miami's tendency to play better when behind in series and in fourth quarters.
That might prove the case, because the Heat haven't yet been seriously challenged in the playoffs. But they'll have to raise their level considerably to match the way San Antonio is playing. Six times this postseason, the Spurs have beaten opponents by 20 points more than an average team in the same situation. Miami has done that only once -- the closeout Game 6 against Indiana.
If the Heat are to win their third consecutive championship, it will mean defying three decades' worth of Finals trends.
Analyzing three decades' worth of Finals trends to anticipate winner
Regression analysis shows one team is significantly favored heading into the NBA Finals.
The Miami Heat and San Antonio Spurs have reached the NBA Finals, setting up a rematch of last year's classic seven-game battle. With four days between the conclusion of the conference finals and Game 1, now comes the real fun: predicting the outcome.
Predicting the NBA Finals is somewhat different from other playoff series. First, there's more playoff data available -- three full rounds against a variety of opponents, giving a better idea of who's playing better right now. Second, because the teams have played each other just twice during the regular season, there's less head-to-head data to determine whether the matchup is good or bad.
So what has really mattered when picking the winner of past Finals? And what does that say about this year's series? Let's take a look.
Matters: Regular-Season Records
Ordinarily, statistical projections will start with point differential. But when it comes to the NBA Finals, during the past three decades, records have matched up better with results than differential.
When the two teams were separated by three games or fewer during the regular season, teams with home-court advantage have actually been more likely to get upset than win the series, going 4-5. But when they won at least six more games during the regular season, they've gone a dominant 16-2, with 1995 (Houston over Orlando) and 2006 (Miami over Dallas) the lone exceptions. That's bad news for the Heat, who finished eight games behind the Spurs in the standings.
Doesn't Matter: Head-to-Head Results
Against conference foes, there is predictive value to the regular-season series between the two teams -- especially in the opening round. That doesn't carry over to the NBA Finals. Two games simply aren't enough to tell us much about how the teams match up.
Half of the past 30 Finalists have split the season series, as Miami and San Antonio did this season. Though nine of the other 15 Finals were won by the team that swept the season series, that doesn't provide much new information because most of those teams had home-court advantage. The lower-seeded team has gone on to win the Finals just once out of the four times it swept in the regular season.
Matters: Playoff Performance
It pays to be hot going into the Finals. When the lower-seeded team had a better point differential during the first three rounds of the playoffs, adjusted for schedule, the series is nearly a toss-up -- the favorites win 57.1 percent of the time (8-6). When the team with home court also has performed better during the playoffs, however, they're a dominant 14-2 (87.5 percent), with 1998 (Chicago over Utah, when the two teams were nearly even leading up to the Finals) and 2006 (Miami over Dallas, again) the exceptions.
The Heat (plus-7.0) and Spurs (plus-8.0) had similar average margins en route to the Finals. However, San Antonio played a much more difficult schedule in the competitive West. So San Antonio's adjusted differential of plus-11.6 points per game is much better than Miami's plus-8.1 mark.
Doesn't Matter: Games Played
Because the Spurs went a full seven games in the first round, the Heat have played three fewer games in the postseason. Turns out that extra rest is not a factor in why playoff performance to date matters in the Finals. In fact, favorites who have played more games (like San Antonio) have actually tended to perform slightly better than expected, possibly because it means they've faced more challenging opposition.
Matters: Defensive Rating
Yes, defense wins championships -- as long as it is paired with a good-enough offense to get to the Finals. The team with the better defensive rating during the regular season has won 19 out of the past 30 Finals, a figure that substantially understates its importance. See, offense-first teams are more likely to have home court in the Finals. When the better defensive team also has home-court advantage, it has won 86.7 percent of the time (13-2). And better defensive teams have frequently pulled upsets without home court, going 6-9 (40 percent) in those series.
Again, the importance of defense favors the Spurs. They were the better defense in the regular season, ranking fourth in points allowed per 100 possessions; Miami finished 11th. The Heat would be the first team to win the championship while finishing outside the league's top 10 defenses since the 2001 Lakers (21st).
Unlike those Lakers, Miami hasn't yet shown the ability to turn on its defense for extended stretches during the playoffs. The Heat reached the Finals largely on the strength of their offense, which dominated the league's No. 1 (Indiana) and No. 6 (Charlotte) defenses. Miami scored 12.9 more points per 100 possessions during the East playoffs than its opponents allowed during the regular season (weighted by games played), but allowed them to score 2.8 more points per 100 possessions than usual.
By contrast, San Antonio's playoff run has been incredibly balanced. In fact, the Spurs have been slightly better on defense (plus-7.4 points per 100 possessions better than opponent averages) than offense (plus-6.9). That kind of balance is rare in the postseason. Just five teams since the ABA-NBA merger have been at least six points better than average per 100 possessions at both ends of the court.
Putting it Together
A regression that combines regular-season win differential and playoff performance leading up to the Finals -- but not defensive rating, which isn't statistically significant as part of a regression -- correctly retrodicts 27 of the past 30 Finals outcomes. Based on that, San Antonio has an 88 percent chance of winning the Finals.
The good news for Miami? As you might guess from going through the indicators, the biggest upset in modern Finals history was pulled off by another Heat team with Dwyane Wade.
http://i58.tinypic.com/2yubzt1.png
Still, nine of the 10 teams most heavily favored entering the Finals won the series, and none of the underdogs even forced a Game 7. The 2006 Finals are also the exception to the rule when it comes to favorites who had a better point differential in both the regular season and the conference playoffs. Those teams are 11-1 in the past three decades.
Despite this overwhelming evidence, the Heat are only slight underdogs to win the series in Las Vegas. The most common line suggests the Spurs have a 57 percent chance to win. In part, the discrepancy can be traced to the popularity of Miami, as two-time defending champion. But it also surely reflects a belief we still haven't seen the best of the Heat, given Miami's tendency to play better when behind in series and in fourth quarters.
That might prove the case, because the Heat haven't yet been seriously challenged in the playoffs. But they'll have to raise their level considerably to match the way San Antonio is playing. Six times this postseason, the Spurs have beaten opponents by 20 points more than an average team in the same situation. Miami has done that only once -- the closeout Game 6 against Indiana.
If the Heat are to win their third consecutive championship, it will mean defying three decades' worth of Finals trends.