The NHL playoffs have many more upsets than the NBA. Adrian the Canadian tells me that this is ruining their product, since the most exciting teams often get unlucky and bow out early. I can’t help but agree — I stopped watching this year after my favorite team (the Red Wings), my local team (the Bruins), and probably the best team (the Penguins) got bounced. The NHL wasn’t always so unpredictable — the Canadiens, Islanders, and Oilers won 13 of 15 cups between 1975-76 and 1989-90. Adrian’s theory is that the the rise of the butterfly goalie has increased save percentages, which makes outcomes more random.
It’s pretty easy to show that increased save percentages do indeed muddy up the result. I generated 1,000 simulated games for three sets of parameters. First, the 1980s (before the butterfly):
- Both teams: 89% save percentage
- Team A: 32 shots per game on average
- Team B: 28 shots per game on average
Then, for the late 90s/early 2000s (butterfly goalies, slightly fewer shots on average perhaps due to popularity of the neutral zone trap): Continue reading
Posted in Common Sense, Hockey, Probability Analysis
Tagged Adrian the Canadian, average goals in the NHL, butterfly goalies, Canada, Coyotes, Detroit Red Wings, effect of butterfly goalies, game series, get rid of shootouts, goaltending has improved nhl, hockey is random, hockey playoff upsets, hockey unpredictable, National Hockey League, neutral zone trap, NHL, NHL playoffs, playoffs, quality team, randomness in hockey, Red Wings, save percentage, shoot outs, shootouts, shootouts are dumb, shootouts lucky, shootouts not fair, Sports, Stanley Cup playoffs, Team B, too many upsets hockey
Following on my general analysis of the Sloan Sports Analytics Conference, here’s a look at the research presentations (you’ll note: nothing on the sports side of football or soccer! I submitted one of each but they were rejected . . . ):
An Expected Goals Model for Evaluating NHL Teams and Players (Brian MacDonald)
This paper tries to predict future performance better by incorporating more measurable statistics than past models (goals, shots, blocked shots, missed shots, hits, faceoff %, etc.). His prediction tests show that he makes improvements, and at the team level, I think these results have some value. However, moving to the individual level in a sport like hockey (or basketball, football, soccer, or rugby) is hard because of complementarities between players. For example, trying to measure one player’s contribution to team wins or goal differential based on the number of shots they take is hopelessly confused with the actions of other players on the ice that affect the quality and number of these shots.
Another issue in the paper is that MacDonald controls for team level statistics (such as faceoff win percentage) in the individual level regressions, when in fact much of player value may be driven by these statistics. For example, one of Red Wing Pavel Datsyuk’s strengths is faceoff win percentage, while one of his weaknesses is hitting. The value that individuals bring through these variables is caught up in MacDonald’s team level control variables. Still, the team-level analysis is a reasonable way to improve what’s out there.
Big 2’s and Big 3’s: Analyzing How a Team’s Best Players Complement Each Other (Robert Ayer)
This paper categorizes the top three players on each team Continue reading
Posted in Baseball, Basketball, Causal Analysis, College Sports, Hockey, Probability Analysis, Research Papers, Sports Stats
Tagged Allan Maymin Philip Maymin, An expected goals model, basketball, Big 2s and 3s, Brian MacDonald, Celtics, CourtVision, cumulative win probabilities NCAA basketball, deconstructing the rebound, Effort vs. Concentration, experience and winning NBA, free throw shooting under pressure, Gartheeban Ganeshapillai, Goldsberry, hockey, James Tarlow, John Guttag, Justin Rao, Kirk Goldsberry, machine learning, Mark Bashuk, Matt Goldman, MIT News, MIT Sloan Sports Analytics Conference, motion tracking analysis NBA, National Basketball Association, National Hockey League, NBA, NBA chemistry, NBA synergies, NHL, optical analysis NBA, optical tracking data, Peter Dizikes, Predicting the Next Pitch, Rajiv Maheswaran, Ray Allen, Rebound (basketball), rebound study wrong sloan sports, research papers Sloan Sports Conference, Robert Ayer, Sloan Sports Conference, Sloan Sports Conference research overview, Sloan Sports Conference review, Sloan Sports Conference summary, spacial analysis NBA, USC rebound study
“But he’s Canadian,” you say, “So what does he know about baseball?” Well, he’s from Toronto, the team most screwed by the current system, so let’s give it a shot:
A few days ago, the MLB announced that it was expanding its playoffs to include a second wild-card team. Under the new system, the two wild-cards will play a single game that determines who goes to the divisional series. Response has been, at best, mixed. The strongest criticisms, like this one from ESPN’s Joe Sheenan, have taken a traditionalist perspective. Sheenan worries about what this new system will mean for deep-seated, and still exciting, elements of baseball like the pennant race. He sees the wild-card system as debasing what has historically been one of the most exciting parts of being a baseball fan: following your team through a tense September race to win the division. By Sheenan’s estimation, the old system encouraged top teams to play their best throughout the whole season. If you happen to be one of the two best teams in the league by regular season record but can’t win your own division, tough grapes.
I sympathize with Sheenan and other traditionalists. Baseball’s regular season is long and arduous and does a pretty good job of determining the “best” team (or, at least, a better job than other pro-sports at determining the best team). Meanwhile, baseball playoffs, due to the nature of the game, are pretty close to random. As Billy Beane said, “my shit doesn’t work in the playoffs” – seven and five game series are simply too short to give us a good idea as to which team is best. In the 17 post-seasons since the advent of the wild-card, the wild card team has won five times Continue reading
Posted in Baseball, Common Sense, Pop Culture, Probability Analysis, Rules Analysis
Tagged Adrian the Canadian, baseball, Billy Beane, Boston Red Sox collapse, coin flip game, coin flip game is dumb, Division Series, ESPN, George Will, Joe Sheenan ESPN, League Championship Series, Major League Baseball, MLB playoff system is stupid, MLB playoff system proposal, MLB playoffs, MLB playoffs new rules, MLB playoffs new system, New York Yankees, pennant race, playoffs, probabilities, St. Louis Cardinals wild card World Series, Tampa Bay Rays, Toronto, Toronto Blue Jays, Wild Card, wild cards, World Series, World Series odds
My buddy Tony and I have been trying to figure out how to quantify Jeremy Lin’s recent five games. He suggested I figure out the likelihood of his start, assuming that Lin is “just” an above average point guard. So, I identified all the point guards who averaged between 16 and 18 points per game in the 2009-10 or 2010-11 season. In 2009-10, that included Devin Harris, Rodney Stuckey, Russell Westbrook, Stephen Curry, Steve Nash, and Tony Parker. In 10-11, the list is Brandon Jennings, Chauncey Billups, Gilbert Arenas (before the suspension), John Wall, Raymond Felton (while with the Knicks), and Tony Parker again.
I collected the game logs for all these guys for the relevant year(s); here’s the histogram of points scored in each game (including playoffs to bump the sample up):
In a total of 832 games, these players scored 30 or more points on 38 separate occasions (this is the total of the last three bars on the right). Likewise, they scored fewer than 5 points in 32 different games. These two tails each capture about 4-5% of the total distribution.
Using this distribution, Continue reading
Posted in Basketball, Prediction, Probability Analysis
Tagged Brandon Jennings, Chauncey Billups, Devin Harris, exact sequence, five games, game logs, game point, Gilbert Arenas, Jeremy Lin, Jeremy Lin analysis, Jeremy Lin assessment, Jeremy Lin hype, Jeremy Lin overhyped, Jeremy Lin overrated, Jeremy Lin point guard, Jeremy Lin points, Jeremy Lin prediction, Jeremy Lin statistics, John Wall, Knick, Lin, New York Knicks, Point guard, Raymond Felton, Rodney Stuckey, Russell Westbrook, Stephen Curry, Steve Nash, three bars, Tony Parker
The Thunder and Warriors played a very entertaining game last night. All the stars showed up (Monta Ellis, career high 48 points; Kevin Durant, 33 points, game winning shot, close to a triple double). The defense wasn’t terrible — the Warriors especially made a bunch of tough shots. Close games like this are generally decided by luck, but there were two interesting decision points in the endgame where each team affected the odds:
Down one, should you shoot early or late?
With about 22 seconds left, down one point, the Thunder had Durant drive right to the hoop and go for a quick shot — air ball, but the Warriors knocked it out of bounds. On the next inbounds play, Durant pulled up immediately and banked in a (relatively) open jumper to take the lead with 16 seconds remaining. This gave the Warriors plenty of time for a rebuttal, and the Warriors announcers were confused that the Thunder didn’t run down the clock to take the last shot.
The Thunder clearly wanted to shoot quickly. Did this help or hurt their chances of winning? It gives the Warriors another chance Continue reading
Posted in Basketball, Probability Analysis, Science
Tagged acceleration equation, basketball, Brandon Rush, brother Evan, Durant game winner, endgame strategy, Golden State Warriors, how long does a ball take to fall, how much time is wasted throw ball in the air, Kevin Durant, laws of motion, Monta Ellis 48 points, Morris Peterson buzzer beater, NBA, Oklahoma City Thunder, physics, Ricky Rubio, Ricky Rubio smart, Warriors Thunder shoot out
The last five years for the Patriots would make many people believe in karma. Since Tom Brady left his baby mama Bridget Moynahan for Gisele and Bill Belichick got caught videotaping other teams’ run throughs, here are the Patriots season results:
- 2007: Crazy late game Super Bowl loss to the underdog Giants
- 2008: Brady tore his ACL early in the season and they missed the playoffs despite going 11-5
- 2009: Brady had a stinker in a first round loss to the Ravens
- 2010: Finished 14-2, but Brady had another stinker in a second round loss to the rival Jets
- 2011: Brady nearly blew it against the Ravens again in the AFC championship game and they sneaked into the Super Bowl, only to suffer another late game loss to the underdog Giants
Gisele continued her negative influence by blaming the loss on drops by the Patriots receivers (only Aaron Hernandez had a truly bad drop, and it was probably too late to matter). The Patriots have 60 wins over the last five years (12 per year), but no rings. If the Patriots go 15-1 next year and get a rematch with a 9-7 Giants team, the Giants will probably be favored. They can’t get past those guys.
Close games are generally decided by luck — Bill Barnwell gets into this at Grantland, but finds himself backtracking almost immediately to avoid angering Giants fans (“The Giants were not lucky to win Super Bowl XLVI because they fumbled twice and fell on both of them.”). There will be no backtracking from me! The Giants were lucky to win (as the Patriots would have been if they had won). Here’s the way the ball bounced Continue reading
Posted in Commentary, Common Sense, Football, Pop Culture, Probability Analysis, Rules Analysis
Tagged 12 men on the field, 2007 New England Patriots season, Aaron Hernandez drop, Aaron Hernandez lost the Super Bowl for the Patriots, AFC championship game, Ahmad Bradshaw, Baltimore Ravens, Barnwell wrong, BenJarvus Green-Ellis never fumbles, Bill Barnwell, Billy Cundiff shank, Bradshaw, Bradshaw declared himself down, Bradshaw should have gone down, Brady, Brandon Jacobs, Bridget Moynahan, Buddy Ryan Polish defense, Buddy Ryan too many men on the field, Danny Woodhead, David Beckham Super Bowl commercial, did the Giants get lucky, Eli Manning, Giants 12 men on purpose, Giants defensive line, Giants fumbles, Giants should have kicked a field goal, Giants strategy Super Bowl, Giants win the Super Bowl, Gisele Bundchen, Gisele criticizes receivers, Grantland, Gronkowksi ankle, Gronkowksi injured, Hakeem Nicks, Justin Tuck, Lawrence Tynes, Madonna old, Madonna stiff, Manning told Bradshaw to go down, Mark Sanchez, New York Giants, New York Jets, Patriot, Patriots bad karma, Patriots have no deep threat, Patriots let the Giants score, Patriots strategy Super Bowl, Patriots unlucky, Randy Moss, Sean Weatherford MVP, should Patriots have let Giants score, statistics, Super Bowl, Super Bowl 46, Super Bowl XLVI, Tom Brady, Tom Brady bad decision interception, Tom Brady safety, Tom Coughlin, Victor Cruz, Victor Cruz fumble, Vince Wilfork, Wes Welker, Wes Welker drops, Wes Welker lost the Super Bowl for the Patriots, win probability Giants
It was a renaissance in Boston last night. Garnett was draining 20 footers, Paul Pierce was driving and kicking and hitting shots, and Jermaine O’Neal was putting the clamps on Dwight Howard. Everybody hustled. The defensive intensity never lapsed all game. To steal a line from NBA TV studio man Brent Barry, the Celtics’ “Jurassic Five” went prehistoric on the Magic and held them to a franchise-low 56 points. It was their first win over a team with a winning record, by 31 points no less.
Recently, I’ve discussed the efficacy of the hack-a-Howard strategy (or as Celtics TV mainstay Tommy Heinsohn puts it, the old “hack the Shaq”). The short answer is that Howard shoots too well from the line (59% almost every year, though lower so far this year) for a pure hack-a-Howard to be effective for most teams. However, hacking Howard only when he has the ball in good position Continue reading
Posted in Basketball, Commentary, Probability Analysis
Tagged 56 points franchise low, Avery Bradley, Avery Bradley defensive weapon, Avery Bradley great defender, Avery Bradley owned Jameer Nelson, basketball, Bass outplayed Davis, Big Baby Davis, Boston Celtics, Brandon Bass, Brent Barry Jurassic five, Celtic, Celtics defended Howard well, Celtics Magic trade Davis Bass, Celtics old, Celtics won the Brandon Bass Glen Davis trade, Doc Rivers, Dwight Howard, E'Twaun Moore, Glen Davis, gold buffalo proof coin commercial, Greg "The Dutch Steamer" Stiemsma, hack-a-Howard, Hedo "the Turk" Turkoglu, Howard, Howard double team, Howard free throw shooting percentage, Howard not Superman, Howard shooting percentage, Howard should pass more, Howard takes bad shots, Howard took too many shots, intentional fouls Dwight Howard, Jameer Nelson turnovers, Jason Richardson, Jermaine O'Neal, Jermaine O'Neal defense, Jurassic Five, Kevin Garnett resurgence, KG, Magic offense uncreative, Marquis Daniels, Max Tall commercial, Max Tall shoe lifts, NBA, NBA TV, NBA TV horrible commercials, O'Neal, O'Neal stopped Howard, Orlando Magic, Paul Pierce, Paul Pierce heel injury, Rajan Rondo, Ray Allen, Sasha "the Dog" Pavlovic, Sasha Pavlovic, should teams double team Dwight Howard, teams should not double team Dwight Howard, the Dutch Steamer, the Steamer, the Turk, Tommy Heinsohn funny quotes, Tony
A couple weeks ago, I argued that the hack-a-Howard strategy could work on a player who shoots 50% from the line. My post was timely; four days later, Mark Jackson instructed his Warriors to foul Howard repeatedly. Howard attempted 39 free throws (an NBA record) and made 21 (54%). The Warriors lost the game, and commentators hammered Jackson for ruining the flow of the game and being afraid to face up to the opposition. Magic coach Stan Van Gundy didn’t really complain but refused to foul 51% career free throw shooter Andris Biedrins in retaliation. However, the Warriors still had a chance to win with 3 minutes left against a far superior opponent. To me, that looks like a success.
What do the numbers say about Jackson’s decision? Well, Continue reading
Posted in Basketball, Innovative Ideas, Probability Analysis
Tagged Andris Biedrins, Andris Biedrins free throw shooting percentage, basketball, Dwight Howard, Dwight Howard free throw shooting percentage, Dwight Howard free throws, Golden State Warriors, hack Howard, hack-a-Biedrins, hack-a-Howard, hack-a-Shaq, Howard attempts 39 free throws, intentional fouls, Mark Jackson, Mark Jackson is an idiot, Mark Jackson shouldn't have hacked Howard, NBA, Orlando Magic, Stan Van Gundy
During Kobe’s “hot streak,” I’ve been writing that he’s actually inefficient compared to Andrau Gasnum, the Lakers’ superb tw0-man post presence. I’ve said that he should give up some shots until his efficiency equalizes with Gasnum’s. Adrian the Canadian was quick to send me a Sloan Sports Analytics Conference paper arguing that teams might equalize offensive efficiency too much already. The author (Brian Skinner) uses some network theory for unknown reasons (it’s not related to his point), but the paper boils down to Continue reading
Posted in Basketball, Probability Analysis, Research Papers
Tagged Adrian the Canadian, Andrau Gasnum, Andrew Bynum efficient, basketball, Brian Skinner, equalizing offensive efficiency, Kobe Bryant, Kobe Bryant dumb, Kobe Bryant efficiency, Kobe Bryant macho, Los Angeles Lakers, marginal benefit, marginal cost, NBA, Paul Gasol efficient, Sloan Sports Analytics Conference
My apologies for missing the last couple days on the blog, but don’t worry, I was hard at work on two projects that I’ve just submitted with a couple other guys to the Sloan Sports Analytics Conference. I’ll have more to say about them soon — one project looks at the effects of temperature, rest time, and turf type on MLS games, and the other examines the true value of winning the NBA draft lottery and measures how much tanking really goes on in the NBA.
In the meantime, Kobe Bryant is lighting up scoreboards and shot charts. He must be reading this blog, but I think all I did was make him angry. He’s taken 31 shots in each of the last three games and managed 40 points in all of them. Reading the ESPN write up from the last one, it looks like we have our new MVP.
However, over those games he’s made 47 shots for a Continue reading
Posted in Basketball, Commentary, Probability Analysis
Tagged Andrau Gasnum, Andrew Bynum, Andrew Bynum efficient, Cleveland Cavaliers, ESPN, great potential, Kobe Bryant, Kobe Bryant expected points, Kobe Bryant inefficient, Kobe Bryant shooting percentage, Kobe Bryant shoots too much, Kobe Bryant true shooting percentage, Kobe Bryant volume shooter, Los Angeles Lakers, Pau "the Gas Man" Gasol, Pau Gasol, Pau Gasol efficient, Phoenix Suns, Sloan Sports Analytics Conference, the Gas Man, two-headed beast Andrau Gasnum, Utah Jazz