Saturday, January 30, 2010

Duke-Georgetown Tempo-Free Preview

Seven inches of powdery white stuff has fallen from the sky this morning, which means it's a perfect time to stay home and analyze basketball statistics. From a tempo-free standpoint, today's game between Duke and Georgetown is an elite matchup. The Hoyas are ranked 15th in the nation by Pomeroy, but have an adjusted offense (19th) and an adjusted defense (32nd) ranking below their overall level. The reason for this is that most teams around their level in the Pomeroy rankings have one excellent score and one mediocre score (e.g. Villanova: 3rd on offense, 71st on defense).

Georgetown's strength of schedule also boosts their Pomeroy ranking. The Hoyas are coming off a blow out loss at Syracuse (3rd Pomeroy), and overall they rate as the 4th toughest schedule in the nation, and have played against the second toughest slate of defenses of all the division 1 teams. While this means that G-Town is battle tested, it also means that their raw offensive and defensive scores are much lower: they have averaged 108.7 points/100 possessions (58th) while giving up 93.1 points/100 possessions (46th). Part of the low offensive output has come while on the road against good teams-- they failed to crack the 1.0 points/possession mark at both Syracaue and Villanova.

Duke, meanwhile, is a well-kept tempo free secret this year. For whatever reason, Duke always seems to be near the top of the Pomeroy rankings in January and February, and this season is no different. Duke currently sits behind only top-ranked Kansas overall, and the Blue Devils continue to have the best adjusted offense in the country. In fact, it has only been in the past week (since the loss at NC State) that Duke has not also had the highest raw offensive efficiency as well (and are still in the top five). Clearly those numbers were going to come down with ACC play, but like Gerogetown, Duke is playing against some pretty tough defenses (6th toughest defense against).

It's hard to put a finger on what exactly is making Duke's offense so good. Pomeroy lists the "four factors" he believes are most critical to consistent play, regardless of the game's pace. Duke is a top 20 team in two of these factors: turnover rate (16.8% of possessions, 14th) and offensive rebounding percentage (40.1% of missed shots rebounded, 15th). Less impressive is the effective field goal percentage (52.9%, 41st) and FTA/FGA (36.4%, 202nd). Clearly the Duke alums have not been paying the refs off enough this year, because they are not getting to the free throw line very often at all. On the bright side, Duke's 77.0% FT% is fourth in the nation.

This is a game that will be won underneath the baskets. The first issue is Duke's shooting ability: while Duke has their characteristic 3-point shooting ability, they have struggled at times shooting from close range, and rank 79th with just 50.6% from inside the arc. Georgetown, meanwhile, struggles to keep opponents' percentages down. Because this game is being played at the Verizon Center, Duke can be expected to miss their fair share of shots. This shifts the focus to a battle between an elite offensive rebounding unit (Duke) and an elite defensive rebounding unit (Georgetown). For Duke's big men, the goal should be to grab that rebound and then go up strong through the usually foul-conscious Greg Monroe. But if the Hoya sophomore can handle Zoubek and the Plumlees, it could be a long afternoon for Duke.

In the rare event that Duke has a lights-out shooting performance on the road, the final tally could get quite high-scoring. One of the things Georgetown does do well is shoot the ball, with a 55.4% eFG% (12th). However, they are not very skilled at the other four factors (offensive rebounding, limiting turnovers, and getting to the free throw line). It's a strange game to predict because if the game were played at Cameron, one could see Duke making their shots and limiting their opponent's strength on the defensive glass, while the Blue Devils dominate their own defensive glass after limiting Georgetown's shooting ability.

But the game is being played in DC's downtown Chinatown, which adds expectation to Georgetown's shooting ability and detracts from Duke's. That's bad news as Georgetown has four players (Freeman, Vaughn, Wright and Clark) who put up eFG% north of 55. A cold shooting night from Duke and road defense as dismal as shown at NC State, and Duke looks to fall in a big way. However, more recent games have shown Duke's defense to be back on solid ground, and so if Georgetown's shooters are cooled, then look for a fight to the finish.

Prediction: Mason Plumlee and Brian Zoubek, combined, have about as much playing time (86.7% minutes played combined) as Greg Monroe (84.7%). Whoever has the most rebounds (MP2 + Zoo vs Monroe) will be on the victorious team.

Friday, January 22, 2010

Worst Duke Defensive Performances

It's been a while since we've done college basketball here, and I have a few things planned for the coming months, including a systematic re-do of last year's tournament simulation. In the meantime, I want to nip any "Matt's a Duke fanboy" criticism in the proverbial bud by doing a negative post about Duke.

The tempo-free era of college basketball began with the 2003-2004 season as Ken Pomeroy started putting posting his rankings based on offensive and defensive efficiency. Duke, for whatever reason, has always done pretty well during the regular season in Pomeroy's adjusted (for opponent offensive and defensive strength) rankings:

Year/Offensive Efficiency/ Defensive Efficiency
2010/1/18
2009/10/20
2008/11/9
2007/40/5
2006/5/13
2005/15/1
2004/2/4

Nevertheless, Duke has put up some hard-to-believe individual games on both sides of the ball. Defense, however, is so intricately tied to Coach K's philosophy that it is the better choice for a comprehensive breakdown. Defensive ability puts players on the floor for Coach K, and can limit the minutes of potentially explosive offensive perimeter players, if they cannot grasp Duke's defensive philosophy (c.f. Taylor King, Elliot Williams, Andre Dawkins). Usually, the result is a solid defensive gameplan that has consistently been in the top 20 the past six and a half seasons.

There have been great defensive efforts, and not always against inferior competition. In fact, the best defensive performance of the 228 games recorded on kenpom.com is this one, played December 19, 2009 against Gonzaga in Madison Square Garden. Duke held the Zags to an efficiency of 57.1, which is absolutely stellar when you consider that Gonzaga's 2009-2010 average is 111.3! But it has not been all good news for Duke this year, and it is an historic defensive lapse that is the reason for this post. Here are the top 10 worst defensive performances since 2003-2004:

#10 (118.4): January 14 2006 at Clemson (Duke W 87-77). We start with a surprising performance in that not only is it a Duke win, but also a win on the road. Although the 2005-2006 Duke team was frequently spotlighted for it's excellent defense, led by Shelden Williams' shotblocking ability, on this night at Littlejohn, things did not go well. Giving up more than a point per possession to a Clemson team that did not make the NCAA tournament and finished 94th in the nation in adjusted defense was simply not acceptable. Duke had some other defensive clunkers along the way, but eventually fell in the NCAA tournament due to their worst offensive performance in the tempo-free era. (But as Alton Brown might say, that's another post...)

#9 (119.0) November 16 2008 vs Rhode Island (Duke W 82-79). This was the night that RIU's Jimmy Barron almost got a permanent middle name from Duke fans. Barron hit seven straight three-pointers before Dave McClure came off the bench to get a hand in Barron's face, causing him to heave an air-ball with 1:24 remaining and Duke down by 2 (ESPN's play-by-play calls the shot a 2-pointer, but I was at the game and remember differently). This was by far the loudest I've heard Cameron in a non-conference game. I also had the pleasure of high-fiving Jimmy Barron as he ran off the court, and I have not washed that hand since.

#8 (119.1) March 8 2009 at North Carolina (Duke L 79-71). This was the closer of the two Duke-UNC games last year, and both teams were had worse efficiencies than the earlier matchup. The pace was 13 possessions slower as well. The biggest standout is that the Tar Heels rebounded over 40% of their missed shots, while Duke's offensive rebounding percentage was a dismal 18.8%. Eww.

#6t (121.3) February 18 2004 at Wake Forest (Duke L 90-84). Duke's best team during the Tempo-Free era only lost six games all season, and every time they did, they allowed more than a point per possession. It was Duke's second loss in a week (they lost at NC State earlier) and is perhaps the best lesson for Chicken-Little Duke fans and Duke haters alike, concerning this year's Duke team. Despite the efforts of the media and the common fan, "consistency" just doesn't mean anything. Especially in ACC road games. A team can put up clunkers in consecutive games in January and still get within an Okafor of the national championship game.

#6t (121.3) January 21 2006 at Georgetown (Duke L 87-84). From the second paragraph of that ESPN recap: "That's my child," the elder Thompson said. "I love my child. After all he's had to go through, he deserves this." Duke never led in a classic execution of the Princeton offense, and JJ Redick scored 41 points, and with Duke almost matching the Hoyas' offensive efficiency with a 117.3 rating. Free throws were the difference, as Georgetown got to the line more often than Duke. It is unclear what the elder Thompson said of Duke's destruction of Georgetown in 2009.

#5 (124.5) February 22 2009 vs Wake Forest (Duke W 101-91). Last year was Duke's worst from a defensive standpoint, and it shows in this top ten list. This game was the polar opposite of the game a few weeks earlier in Winston-Salem, a two point loss for Duke in which neither team topped 95 in efficiency. The rematch in Cameron however had a similar number of possessions and basically no defense.

#4 (125.8) February 20 2005 vs Wake Forest (Duke W 102-92). An eerily similar game to the one above, although this rematch played out exactly like the preceding game at Wake Forest (see below); the only difference was the result for Duke. Interesting point about the 2004-2005 Duke team; if you check here, you can see all the factors that were correlated to Duke's defensive performance that year. Interestingly, nearly all the factors are in bold, indicating a significant (at the 95% confidence level) correlation. Duke's defensive performance that year was strongly tied to their opponents' shooting, rebounding ability, turnover rate, and ability to get to the free throw line. Defense was also significantly correlated to Duke's own offensive ability that night, especially on Duke's offensive glass. It should come as no surprise, then, that Duke was knocked off in the Sweet 16 in a game to a Michigan State team that was among the best in offensive rebounding, among other things.

#3 (127.0) January 19, 2010 at NC State (Duke L 88-74). Ah, the inspiration for this post. Duke was outplayed on their defensive end in a big way, and NC State was helped by a healthy 62.7 effective field goal percentage. They also protected the ball, turning it over on just 13% of their possessions, and turnover rate seems to be a relative strength of this year's Wolfpack team. Offensive efficiency, however, has not exactly been consistent for NC State, and while they put up similar numbers against Georgia Southern and UNC-G, an effort like this against a top-20 defense was completely unexpected. I see no reason to see the game as anything other than a fluke for Duke, and while winning at Littlejohn tomorrow will be a tough task, if Duke loses it will not be due to another defensive calamity. For this, in K, I trust.

#2 (127.6) February 11 2009 vs North Carolina (Duke L 102-87). Easily the worst Duke game I have ever attended, as Duke was never really in this game. Unlike some of the other games, this was not a defensive lapse against an otherwise mediocre offense. This was a lashing at the hands of the eventual champs who could not stop two All-Americans from doing whatever they want on the court. Yes, I'm a little bitter that I slept outside in a tent to watch this game. Next.

#1 (131.6) February 2 2005 at Wake Forest (Duke L 92-89). So many surprising things about this list, including the number of home games (4) and the number of Duke wins (4) and the number of appearances by the Demon Deacons (4). There is quite a wide gap between #2 and this game, and Duke almost pulled off the win! This was a collision of elite squads, as Duke finished the 04-05 season with the best defense in the nation, while Chris Paul's team was the #2 offense. Wake's inability to stop anyone came back to bite them in March, as they couldn't shoot their way out of early exits in both the ACC and NCAA tournaments.

To be fair, Wake Forest dominated the the middle 36 minutes of the game and it was only the 3-point abilities of the talented Mr. Redick that brought the game close at the end: JJ hit three from beyond the arc and Sean Dockery made it 90-89 with two seconds left. Taron Downey hit both of his free throws and Redick missed a running three to end the game. Notably, Duke's offensive efficiency in this game was 127.3, and so one must conclude that it was indeed Duke's defense that prevented the win. As the rematch (see #4) showed, home court has a lot to do with the outcome of games like these.

The biggest absence from this top 10 list: games in March. For all of the hate heaped upon Duke for its struggles in the month of March, not once did they make an NCAA tournament exit due to a sudden lack of defense. In fact, the worst NCAA tournament performance is (predictably) the 2007 first-round loss to VCU, which is 27th on the list at 112.0, followed by last year's win over Texas (36th at 109.3). But those games are miles from the ones above, and allowing around 110 points/100 possessions is probably to be expected from some of the elite offenses in the nation. Coach K gets his teams prepared on the defensive end for March, combined with playing non-ACC teams unfamiliar with Duke's defensive style. There are relatively more games in ACC tournament on the list.

I have compiled the stats from kenpom.com from all years into one spreadsheet, which can be found here for your sorting pleasure. Tempo-free stats can tell us a lot about a team that we weren't expecting to hear. This would be not-so-subtle foreshadowing of a future post about Duke. For a further hint, see this and this.