Saturday, October 2, 2010

ACC Prediction - The Harrison Barnes Effect?

Do Top 10 Recruits Really Make a Difference?

When I start to share my conference predictions, the first thing that is going to jump into your head is that I am clearly under-valuing elite recruits. But the next table should illustrate the reason. On average, teams that rely heavily on Top 10 freshman do not perform substantially better than the previous season.

Once you control for the other factors impacting the team (players leaving, player development), you do get a positive impact from top 10 recruits. But on average, it is not nearly as large as most people expect.

There are two problems here. First, there are top 10 recruits that were simply disappointing. (Think John Henson for North Carolina or Lance Stephenson for Cincinnati last year.)

Second, consider the alternative. If a top 10 recruit did not show up, they would not necessarily be replaced by a player with a 75.9 ORtg. Top 10 recruits tend to go to programs that have pretty good alternatives. For a quality team like Duke in 2008, what would have happened if there was no Kyle Singler? Well, Taylor King, Nolan Smith, or Brian Zoubek might have earned more playing time. And while Coach K clearly had his reasons for limiting those player’s minutes in 2008, they were all very effective when on the court. In other words, we have a value over replacement player (VORP) issue. For super talented teams, adding a top 10 recruit usually takes playing time away from other very talented players.

Do not misunderstand what I am saying. As Luke Winn and others have shown, top 10 recruits are often difference makers on the court. But basketball is still a team game. To expect one player (Harrison Barnes) to catapult North Carolina into the top 10 is optimistic. The team still loses its best player in Ed Davis and one of its top scorers in Deon Thompson. If Harrison Barnes only replaces Ed Davis’ production, the team will be treading water. For North Carolina to get better, it is going to require that other players develop at a rapid pace. Can Larry Drew finally cut down on his turnovers? Can Tyler Zeller finally stay on the court?

Or will North Carolina’s rebuilding project follow the path that Connecticut took earlier this decade? In 2006, a deep and talented UConn team lost to George Mason in the regional final. Then after seeing numerous players depart for the NBA, UConn went 6-10 in 2007. And it was not until 2009 that UConn returned to the Final Four.

If North Carolina returns to being an elite team it should qualify as a pleasant surprise. It should not be the expectation.

ACC Prediction

I’ll explain my model again in future posts if you missed it this spring. Suffice to say, I am going to try to replicate what most analysts do in their head. I’m going to look at players that leave and players that return and make a statistical prediction.

Technically, I’m going to look at the drop in efficiency we should expect based on the possession-weighted Dean Oliver statistics of departing players. If a team loses a player with an ORtg of 120 who shoots a lot, that will hurt that team’s predicted efficiency rating. If a team loses a player with an ORtg of 120 who shoots a little, that will hurt less. And if a team loses a player with an ORtg of 85, that will not have a negative impact on the team.

The first table shows the predicted changes in efficiency margin for the ACC teams. At the top we see Virginia Tech. The Hokies return a player-of-the-year candidate in Malcolm Delaney and lose almost no one from last year’s team. (I included the fact that JT Thompson is out for the season in the model.) That means Virginia Tech is going to be better.

On the opposite end of the spectrum, Georgia Tech, Maryland, Wake Forest, and Duke all suffered major player losses in the off-season. Duke makes up for those slightly by bringing in a top 10 recruit in Kyrie Irving.

The key thing I added to my model this summer is the defensive player statistics. This allows a more detailed prediction of why efficiency margins may change. The next table shows what the model predicts will happen to each team’s adjusted offensive efficiency and adjusted defensive efficiency.

As an example, Maryland loses some incredible offensive players, but retains some of its best defensive players. Jordan Williams, who was one of the top defensive rebounders in the entire ACC, and Sean Mosley who had the top steal rate on the Terrapins, are back. Thus while Maryland’s offense should be significantly worse, my model predicts a slight improvement in the Maryland defense.

Similarly, Chas McFarland struggled offensively last season for Wake Forest. But the team will miss his defensive intensity in the middle. Wake Forest’s offense is expected to take a small step back this year, but the defense is expected to take a major step back.

Everything I’ve listed above makes intuitive sense to me. But I’m not as satisfied with the projected ACC standings, which I present in the next table. These don’t quite add up to what most people are predicting. For example, Maryland and Boston College seem a bit high, and North Carolina seems a bit low.

But what the predictions really say is that outside of Duke, the ACC is wide open. Virginia Tech should be good, but the difference between the teams in the middle of the ACC is almost meaningless. The final standings will depend on which players surprise us by developing more than expected.

I’ve read some people who like Wake Forest as a sleeper team based on all the top recruits. But based on the poor defense Bzdelik displayed at his previous job, and the lack of returning starters, even a lineup of top 100 freshmen is going to have a hard time playing at an elite level right away. Jeff Bzdelik has been a great offensive mind and I expect him to turn Wake Forest into a dominant offensive team in the next few years. But remember that the ACC tends to eat its young. In any other BCS conference, Wake Forest would be predicted to finish in the middle of the pack. In the ACC, they are predicted to finish in last.

In the end, these ACC standings are not very satisfying to me because they do not conform to popular opinion. But as you will see in the next few weeks, many other conferences come closer to matching expectations.