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TwoDukeTattoos
12-03-2008, 10:56 AM
Incredible stats philosophy on this site. Before last night's game, Duke was ranked #10 Now they are #4.

http://kenpom.com/rate.php

gw67
12-03-2008, 11:23 AM
Based on a few games, the top teams in the latest Sagarin ratings look reasonable to me. I haven’t seen Pitt play but UNC, Duke, UConn, Gonzaga, Tennessee and Georgetown appear to be among the elite based on my observations. The only pretenders in his Top Ten, IMO, are Clemson and Syracuse. The ACC is rated the top conference by a whisker over the Big East. I doubt that this will last.

http://www.kiva.net/~jsagarin/sports/cbsend.htm

gw67

Dr. Rosenrosen
12-03-2008, 11:36 AM
The useless part of these ratings at this point in the season is strength of schedule since it is only based on games that have been played. Obviously this becomes more meaningful as the year progresses.

Wander
12-03-2008, 11:41 AM
Wow, I think the second tier of teams behind UNC is Gonzaga, Duke, Pitt, and UConn - I'm surprised that these stats agree with me so early.

gotham devil
12-03-2008, 01:53 PM
http://www.vegasinsider.com/college-basketball/story.cfm/story/786801

Duke is up to number 2 in the oddsmakers' poll and would be about a 6 point underdog to the current #1 team in the land on a neutral court.

Lulu
12-03-2008, 05:32 PM
http://www.vegasinsider.com/college-basketball/story.cfm/story/786801

Duke is up to number 2 in the oddsmakers' poll and would be about a 6 point underdog to the current #1 team in the land on a neutral court.

Better make your bets quick, in the future odds UCLA is still ahead of Duke at 7/1. Duke @ 10/1. UNC of course is at 5/2, I'd like to bet against that. It's rare for Duke's odds not to be extremely overinflated.

gw67
12-04-2008, 10:39 AM
The latest Sagarin team and league ratings are posted and it is remarkable how, with minor exceptions, they generally mirror my early impressions.

http://www.usatoday.com/sports/sagarin/bkc0809.htm?loc=interstitialskip

The ACC is still the highest rated conference but just barely ahead of the Big East, Big 12 and Big Ten. I suspect that the ACC will be overtaken by the Big East when the OOC season is completed.

A more interesting list are the teams within the ACC. UNC, Duke, Clemson and Wake are the top four teams with Miami the sixth team. As the season progresses, I expect the positions of Clemson and Wake will flip and Miami will move up to 5th. Virginia is at the bottom and the 7-12 teams seem reasonable although I would expect Virginia Tech to move up to 6th and Maryland back to 7th when we get into ACC play.

I still expect the ACC to get six teams into the NCAAT.

gw67

TwoDukeTattoos
03-01-2009, 06:21 AM
...it's interesting to note that Duke is currently ranked #6 in defensive effeciency and #7 in offensive effeciency. This is significant simply because the ever since the Pomeroy Ratings have been kept, every eventual National Champion has ranked in at least the top 12 in both O and D effeciency. Currently, Duke is the only team in the country to meet both of those criteria.

Of course, this doesn't mean that we'd be a solid pick to win it all. After all, last year's Duke team was also ranked within 12 in both O and D efficiency and we all see how that turned out! Still, with better rebounding this year, you have to like our chances a little more.

EasternDB
03-01-2009, 07:43 AM
UK @ 36, That's a joke...

Olympic Fan
03-01-2009, 10:36 AM
This thread is a bit confusing since it contains several early and out-of-date listings. If anybody is interested, the current ratings -- as of Sunday morning, March 1 -- for Duke are:

No. 2. RPI (Duke was No. 3 Saturday morning, but flipflopped with UNC after Saturday's games).
No. 4. Sagarin
No. 5. Pomeroy

Interesting that the three major computer rankings and the two major polls give us four different No. 1 teams:

Both polls pick UConn
The RPI picks Pittsburgh
Sagarin picks North Carolina
Pomeroy picks Memphis

[Which leads me to downgrade Pomeroy's predictions]

Also, all three major computer polls rank the ACC as the No. 1 conference and the Big East as No. 3. RPI and Sagarin have the Big 10 as No. 2 ... Pomeroy has the Pac 10 as No. 2 (more reason to distrust Pomery).

mehmattski
03-01-2009, 12:19 PM
This thread is a bit confusing since it contains several early and out-of-date listings. If anybody is interested, the current ratings -- as of Sunday morning, March 1 -- for Duke are:

No. 2. RPI (Duke was No. 3 Saturday morning, but flipflopped with UNC after Saturday's games).
No. 4. Sagarin
No. 5. Pomeroy

Interesting that the three major computer rankings and the two major polls give us four different No. 1 teams:

Both polls pick UConn
The RPI picks Pittsburgh
Sagarin picks North Carolina
Pomeroy picks Memphis

[Which leads me to downgrade Pomeroy's predictions]

Also, all three major computer polls rank the ACC as the No. 1 conference and the Big East as No. 3. RPI and Sagarin have the Big 10 as No. 2 ... Pomeroy has the Pac 10 as No. 2 (more reason to distrust Pomery).

Not so sure why you are so quick to dismiss Pomeroy because the statistics don't agree with your personal opinions. The ratings are based on empirical evidence and reflect actual performance in actual games. Also, if you check the archives, nearly every year the national champion has finished #1 or #2 in Pomeroy's rankings (the lone exception is 2003 Syracuse, who finished fifth).

The main difference between Pomeroy and Sagarin is that Pomeroy considers points scored/allowed, adjusted for the number of possessions a team has. For those who don't know, there's a huge difference between scoring 100 points on 50 possessions and 100 points on 100 possessions. The former team will have much more success overall. Sagarin considers only the win-loss records of teams, opponents, and opponents' opponents. The RPI is very similar in this regard.

So, the reason Pomeroy has Memphis as the #1 team in the country is because, by Pomeroy's "Defensive Efficiency Rating," Memphis has by far the best defense in the nation (http://kenpom.com/rate.php?s=AdjDE). For every 100 possessions, Memphis' opponents score just 80 points. That's better than the runner-up (Louisville) by 4 points. They've done this while playing an above-average slate of offenses. For example, in their win at Gonzaga on February 7, Memphis held Gonzaga to just 80.9 points/100 possessions. The Zags' offense averages 113.7, and hadn't had a single game below 95 all season. That is some stifling defense.

Anyway, I hope you consider the methodology behind the rankings. Pomeroy is not intended to be predictive beyond the next few games, because the rankings are constantly updated by a team's actual performance.

COYS
03-01-2009, 12:49 PM
Not so sure why you are so quick to dismiss Pomeroy because the statistics don't agree with your personal opinions. The ratings are based on empirical evidence and reflect actual performance in actual games. Also, if you check the archives, nearly every year the national champion has finished #1 or #2 in Pomeroy's rankings (the lone exception is 2003 Syracuse, who finished fifth).

The main difference between Pomeroy and Sagarin is that Pomeroy considers points scored/allowed, adjusted for the number of possessions a team has. For those who don't know, there's a huge difference between scoring 100 points on 50 possessions and 100 points on 100 possessions. The former team will have much more success overall. Sagarin considers only the win-loss records of teams, opponents, and opponents' opponents. The RPI is very similar in this regard.

So, the reason Pomeroy has Memphis as the #1 team in the country is because, by Pomeroy's "Defensive Efficiency Rating," Memphis has by far the best defense in the nation (http://kenpom.com/rate.php?s=AdjDE). For every 100 possessions, Memphis' opponents score just 80 points. That's better than the runner-up (Louisville) by 4 points. They've done this while playing an above-average slate of offenses. For example, in their win at Gonzaga on February 7, Memphis held Gonzaga to just 80.9 points/100 possessions. The Zags' offense averages 113.7, and hadn't had a single game below 95 all season. That is some stifling defense.

Anyway, I hope you consider the methodology behind the rankings. Pomeroy is not intended to be predictive beyond the next few games, because the rankings are constantly updated by a team's actual performance.

The efficiency statistics are the reason why Pomeroy's statistics have tended to be so accurate, as well. Pomeroy also considers the luck factor, which allows him to avoid weighting a fluky win or a number of fluky wins too heavily, assuming that the winning or losing team plays far better or far worse against a certain team when that team has not displayed that type of play against similarly rated teams. This makes sense, as I think we all can agree that Duke is neither 40 points better than Maryland nor 27 points worse than Clemson.

I'm no statistician, although his explanation of his methodology is very interesting and makes a lot of sense to me, personally. http://kenpom.com/blog/index.php/weblog/ratings_explanation/

darthur
03-01-2009, 01:12 PM
Sagarin considers only the win-loss records of teams, opponents, and opponents' opponents. The RPI is very similar in this regard.

I am not sure where you are getting this from. Sagarin has nothing to do with the RPI, and it most certainly does account for score differential:



In ELO CHESS, only winning and losing matters; the score margin is of no consequence,
which makes it very "politically correct". However it is less accurate in its predictions for
upcoming games than is the PURE POINTS, in which the score margin is the only thing that matters.
PURE POINTS is also known as PREDICTOR, BALLANTINE, RHEINGOLD, WHITE OWL and is the best single PREDICTOR
of future games.
----------------------------------------------------------------------------------------------------------------
The overall RATING is a synthesis of the two diametrical opposites, ELO CHESS and PURE POINTS (PREDICTOR).


Both are sophisticated models, and far superior to RPI by any reasonable metric.

darthur
03-01-2009, 01:22 PM
The efficiency statistics are the reason why Pomeroy's statistics have tended to be so accurate, as well. Pomeroy also considers the luck factor, which allows him to avoid weighting a fluky win or a number of fluky wins too heavily, assuming that the winning or losing team plays far better or far worse against a certain team when that team has not displayed that type of play against similarly rated teams. This makes sense, as I think we all can agree that Duke is neither 40 points better than Maryland nor 27 points worse than Clemson.

I'm no statistician, although his explanation of his methodology is very interesting and makes a lot of sense to me, personally. http://kenpom.com/blog/index.php/weblog/ratings_explanation/

All ratings systems account for the fact that there is variance in results, and none would conclude that Duke is 40 points better than Maryland from just the one game.

I think you may just be a little confused about what Pomeroy's luck factor really is:


The easiest one to understand is Luck, which is the deviation in winning percentage between a teamís actual record and their expected record using the correlated gaussian method. The luck factor has nothing to do with the rating calculation

The luck factor on his site is just a curiosity. What this means is he runs his calculations from his ratings to guess what would happen if the entire schedule were replayed from scratch. If a team did better in real life than Pomeroy would predict the team would do if it were to redo the schedule, that team has a high luck rating. The luck is calculated only after the rankings and is not used for the rankings at all.

COYS
03-01-2009, 01:26 PM
All ratings systems account for the fact that there is variance in results, and none would conclude that Duke is 40 points better than Maryland from just the one game.

I think you may just be a little confused about what Pomeroy's luck factor really is:



The luck factor on his site is just a curiosity. What this means is he runs his calculations from his ratings to guess what would happen if the entire schedule were replayed from scratch. If a team did better in real life than Pomeroy would predict the team would do if it were to redo the schedule, that team has a high luck rating. The luck is calculated only after the rankings and is not used for the rankings at all.

Yes, I was trying to avoid a technical analysis, but I do understand the premise of Pomeroy's luck factor.

DukieBoy
03-01-2009, 06:45 PM
Just another observation, but after clicking on Duke to bring up the schedule and etc., I scrolled down to the bottom where it described each player's involvement in the team. Both Greg Paulus and Lance Thomas provided little contribution and Dave McClure was nearly invisible. I understand that these conclusions are based off stats only and none of these three put up amazing stats, but...

Guess that means those guys are pretty dispensable right? :)

ice-9
03-01-2009, 10:30 PM
Also, if you check the archives, nearly every year the national champion has finished #1 or #2 in Pomeroy's rankings (the lone exception is 2003 Syracuse, who finished fifth).

The caveat though is that the final ratings *include* NCAA tournament performance, i.e. the extra 6 wins against top competition. So if the champion isn't consistently near the top there'd be something very wrong with the rating system.

What would be more interesting is, going into the NCAA tournament, how well Pomeroy's rankings determined the eventual champ.

wisteria
03-02-2009, 01:19 AM
This is significant simply because the ever since the Pomeroy Ratings have been kept, every eventual National Champion has ranked in at least the top 12 in both O and D effeciency.


Interesting. Is it final ranking after the NCAA tournament?

wisteria
03-02-2009, 01:20 AM
What would be more interesting is, going into the NCAA tournament, how well Pomeroy's rankings determined the eventual champ.

Exactly what I was thinking.

mehmattski
03-02-2009, 08:13 AM
Exactly what I was thinking.

Of course, last year was strange since all #1 seeds made the final four, but Pomeroy gave each of them a pretty strong chance of doing so, based on his own ranking system:

East and Midwest preview (http://www.basketballprospectus.com/article.php?articleid=252)

South and West preview (http://www.basketballprospectus.com/article.php?articleid=257)

In the East, Pomeroy gave Louisville (a 3 seed) a better chance a the Elite 8 than the 2 seed (Tennessee), which proved correct. In the Midwest, Pomeroy didn't exactly see Villanova or Davidson coming, although Villanova did get an 11% chance at making the Sweet Sixteen, which they did.

In the South, Pomeroy correctly predicted the Sweet Sixteen, Elite Eight, and Memphis winning the region. The biggest disparity was in the west, where Duke and UConn were projected to have much stronger Elite Eight possibilities than was realized...

Overall, Pomeroy gave Kansas a 36% chance of winning it all, highest by far for any team, and a greater than 50% chance of making the final. I think the pre-tournament rankings were quite prophetic last year. I'd have to dig back into his old blog archives to discuss previous seasons.

robed deity
03-02-2009, 10:59 AM
From looking at numbers over the years, it seems rare that a national champion does not have a high KenPom ranking. In fact, since 1999, only once did a team win the national championship and end up ranked outside of the top 2 (Syracuse, 5th in 2003). Granted, these rankings I am looking at from Pomeroy's site were the final rankings, and therefore a result of the tournament games, so it is difficult to say exactly where these teams were before the start of the NCAA's. But, then again, its hard to climb up through the efficiency rankings so quickly in just 6 games.

Also, the eventual national champion usually has a top ten ranking in both offense and defense. I seem to remember an article on CNNSI (Luke Winn maybe?) that illustrated this with numbers from the past decade or so. On Pomeroy's site, it only goes back 4 years or so with specific offense and defense ratings, so Im not sure where Winn got his info. Just looking at the past 4 years, Florida from '07 was the only team without a top ten rating in O AND D, and its D was on the cusp at 12th.

Interestingly, guess who is the only team presently with an O and D rating in the top 10?
Thats right, our Blue Devils (at 6th and 8th, respectively). But then again, if any year was to break the trend of having a high efficiency rating and winning the title, it would be this one. There just aren't any great teams out there, and the current KenPom numbers show this. For instance, Oklahoma's current D rating (48th) in most years would eliminate them from championship or final four talk, but I think any reasonable mind would contend they have a legit chance.

rsvman
03-02-2009, 01:00 PM
For the last two seasons I have filled out four brackets. One goes straight seeds, one on RPI, on one Sagarin, and one on my own picks. Each year my own picks have beat all 3 other methods.

I have not yet tried using Pomeroy. Guess I'll have to start that this year. Possibly Pomeroy would finally be the system that could out-predict me.

mehmattski
03-02-2009, 05:35 PM
As a follow up, here are the results of Pomeroy's system (http://kenpom.com/blog/index.php/weblog/2007/03/P12/) making predictions just prior to the tournament in 2007:

South: Pomeroy made the correct Ohio State pick for the final four. Memphis was given a slightly worse chance of making the Elite Eight than Texas A&M. Those three teams and Tennessee were given the best chances at Sweet Sixteen berths, and all were correct.

East: North Carolina (49%) and Georgetown (32%) were given the bulk of the odds to make the final four, and indeed did match up in a classic elite eight game. The other sweet sixteen participants, USC and Vanderbilt, were not heavily favored to make that round; Texas and WSU were given the nod.

Midwest: Pomeroy predicted this would be a "wide open region, with six teams given at least a 5% chance of making Atlanta." In the end, only two major upsets happened in that bracket (Winthrop over Notre Dame and UNLV over Wisconsin). Had you filled out your bracket according to Pomeroy, the sweet sixteen would have been Florida-Maryland-Wisconsin-Notre Dame, and only one of those teams made it through. Pomeroy did not see UNLV coming.

West: The top four seeds in this region made the Sweet Sixteen, but Pomeroy did not get it right. His top four percentages for that round went to Kansas-UCLA-Duke-Southern Illinois, and in fact Pitt was given a better chance than the Salukis.

North Carolina was given the best chance at a title, followed by Kansas. Pomeroy got half the final four right, and six of the elite eight.

For the past two years, that gives him 6 of 8 final four teams (75%) and 12 of 16 elite eight teams (also 75%). How did pre-tournament Sagarin and RPI do?

MChambers
03-04-2009, 11:47 AM
The rankings at the top are more compressed, if you will, than has been the case since 2006. That is, the top teams have lower Pythagorean scores than in 2007 and 2008. The difference looks significant to me, but what do I know. I assume this compression means that the NCAA tournament will be more wide open, with fewer favorites reaching the Final Four.

hurleyfor3
03-04-2009, 12:01 PM
I think some people here are confusing cause and effect.

The prior Pomeroy polls include the NCAA Tournament games, and are weighted towards the most recent games played. So naturally the national champion will end up with a high rating. Also, the 2007 and 2008 FFs had all high-seeded teams playing (1s and 2s), whereas no #1 made the Final Four in 2006. So the Pomeroy season-end ratings from these years will be top-heavy.

This year's tournament hasn't happened yet, so it's not entirely valid to compare the current rankings to those of prior years.

MChambers
03-04-2009, 12:47 PM
I think some people here are confusing cause and effect.

The prior Pomeroy polls include the NCAA Tournament games, and are weighted towards the most recent games played. So naturally the national champion will end up with a high rating. Also, the 2007 and 2008 FFs had all high-seeded teams playing (1s and 2s), whereas no #1 made the Final Four in 2006. So the Pomeroy season-end ratings from these years will be top-heavy.

This year's tournament hasn't happened yet, so it's not entirely valid to compare the current rankings to those of prior years.

You are right, of course, but I still think the top teams at this point in the season are closer together and to the rest of the world than often has been the case. I guess there is no way to prove it, without some exhausting research.

MIKESJ73
03-04-2009, 01:53 PM
Pre Tournament RPI of the last five final fours:

2004: #1, #5, #6, #16 #5 won
2005: #2, #6, #12, #21 #6 won
2006: #9, #13, #15, #26 #15 won
2007: #1, #2, #6, #9 #6 won
2008: #1, #3, #4, #5 #5 won

2008 was as much of an anamoly as 2006.

On a side note, Duke is now #1 in RPI

camion
03-04-2009, 02:04 PM
But, but, but, the RPI is not designed to rank teams according to their relative strength or to predict winners. That is not its function. Sagarin and Pomeroy are better designed for that purpose.

RPI is an indicator that a team plays pretty well and plays a strong schedule. For the RPI it's the schedule that really matters.

gotham devil
03-04-2009, 02:52 PM
Pre Tournament RPI of the last five final fours:

2004: #1, #5, #6, #16 #5 won
2005: #2, #6, #12, #21 #6 won
2006: #9, #13, #15, #26 #15 won
2007: #1, #2, #6, #9 #6 won
2008: #1, #3, #4, #5 #5 won

2008 was as much of an anamoly as 2006.

On a side note, Duke is now #1 in RPI
http://realtimerpi.com/rpi_Men.html

I was glad to see we've now passed Pitt for #1 in RPI.

mehmattski
03-04-2009, 04:20 PM
I think some people here are confusing cause and effect.

The prior Pomeroy polls include the NCAA Tournament games, and are weighted towards the most recent games played. So naturally the national champion will end up with a high rating. Also, the 2007 and 2008 FFs had all high-seeded teams playing (1s and 2s), whereas no #1 made the Final Four in 2006. So the Pomeroy season-end ratings from these years will be top-heavy.

This year's tournament hasn't happened yet, so it's not entirely valid to compare the current rankings to those of prior years.

That is why I cited Pomeroy's own pre-tourney predictions for 2008 and 2007. He was pretty darn good at predicting from the Sweet Sixteen on in both years, based on his own rankings. These would be based on a team's performance immediately following the conference tournaments in those years, which avoids the bias you're talking about.

dcarp23
03-06-2009, 08:48 AM
One really interesting trend is that since Elliot Williams' introduction into the starting lineup, Duke's defensive efficiency has gone down and its offensive efficiency has gone up. I'd bet if you asked the casual observer, he would have said otherwise. Duke is now the fifth most efficient offensive team in the country according to Pomeroy.

If I had to guess the reason for the change, I'd point to two factors: 1) Scheyer at the point and the complete disappearance of turnovers. 2) An increase in steals on the defensive end leading to a significant increase in runouts and easy baskets that were nonexistent earlier in the season.

MChambers
03-06-2009, 09:08 AM
One really interesting trend is that since Elliot Williams' introduction into the starting lineup, Duke's defensive efficiency has gone down and its offensive efficiency has gone up. I'd bet if you asked the casual observer, he would have said otherwise. Duke is now the fifth most efficient offensive team in the country according to Pomeroy.

If I had to guess the reason for the change, I'd point to two factors: 1) Scheyer at the point and the complete disappearance of turnovers. 2) An increase in steals on the defensive end leading to a significant increase in runouts and easy baskets that were nonexistent earlier in the season.

Has defensive efficiency gone down? Williams seems to be playing good man defense, although perhaps he is not so good on help defense (most freshmen aren't). Or is Nolan that much better? Or is it that Zoubek's minutes have decreased? Or something else more subtle?

tbyers11
03-06-2009, 09:24 AM
One really interesting trend is that since Elliot Williams' introduction into the starting lineup, Duke's defensive efficiency has gone down and its offensive efficiency has gone up. I'd bet if you asked the casual observer, he would have said otherwise. Duke is now the fifth most efficient offensive team in the country according to Pomeroy.

If I had to guess the reason for the change, I'd point to two factors: 1) Scheyer at the point and the complete disappearance of turnovers. 2) An increase in steals on the defensive end leading to a significant increase in runouts and easy baskets that were nonexistent earlier in the season.
It's all relative.

Duke's defensive efficiency in the last 5 starting with the St John's game has averaged 105.72, according to Ken Pom (http://kenpom.com/expsked.php?team=Duke). While this is a considerably worse defensive efficiency that the season as a whole at 88.7, it is considerably better than the 114.88 mark in the 4 games (@Clem, UVa, UNC, @BC) that preceded St. Johns and were the impetus for the lineup change.

I don't think that we are playing as good of defense in the last 5 games as earlier in the season, but when you factor in the level of competition and the familiarity of conference foes with each other I don't think the difference is that large and I definitely feel it is a big improvement over the 4 games before Elliot's insertion into the starting lineup.

I agree with you and am excited by the somewhat unexpected and significant bump in offensive efficiency in the last 5 games.

dcarp23
03-06-2009, 09:28 AM
Has defensive efficiency gone down? Williams seems to be playing good man defense, although perhaps he is not so good on help defense (most freshmen aren't). Or is Nolan that much better? Or is it that Zoubek's minutes have decreased? Or something else more subtle?

Great question--it would be nice to be able to look at the stats before the St. John's game (or before the Clemson game) and see what stats changed. It seems to me that the change began when teams made it their game plan to get into the paint and to the rim, which had not happened at the beginning of the year. The cause of that has been debated here ad nauseam, obviously.

That said, Duke's D still ranks 12th in the country, which isn't too bad.

Chitowndevil
03-06-2009, 10:07 AM
Great question--it would be nice to be able to look at the stats before the St. John's game (or before the Clemson game) and see what stats changed. It seems to me that the change began when teams made it their game plan to get into the paint and to the rim, which had not happened at the beginning of the year. The cause of that has been debated here ad nauseam, obviously.

That said, Duke's D still ranks 12th in the country, which isn't too bad.

It isn't good either, considering (1) Duke had been ranked either #1 or #2 in DE pretty much continuously through the end of January, and (2) through their last nine games, Duke has had only one (at VT) in which an opponent had an effective FG% (like FG%, but gives extra weight to made 3s) below 50%. Before that, Duke had allowed an opponent eFG% above 50% only 5 times in 21 games.

Of course you can't argue with the offensive numbers since the lineup change: in its last five games, Duke has turned the ball over on less than 15% of possessions, and shot 2 free throws for every field goal attempted. Both of those are phenomenal figures and well above Duke's season averages (yes it's a sample of only five games, but to put up those kind of numbers late in the season against quality competition is still very encouraging).

My own opinion is the decline in Duke's D has less to do with Williams and Scheyer than with Nolan Smith, who was tremendously effective pressuring the ball early in the year but fell off in mid January. I suspect this has more to do with Nolan's health than his game, but that is conjecture. But since I'm stating opinion at this point, I might as well say I don't think Duke will make a deep March run with the kind of defensive numbers they've put up recently. However, if Nolan Smith can get back to his early January form and Duke can use Williams and Smith interchangably and/or together to pressure the ball, I like Duke's chances.

calltheobvious
03-06-2009, 12:24 PM
It isn't good either, considering (1) Duke had been ranked either #1 or #2 in DE pretty much continuously through the end of January, and (2) through their last nine games, Duke has had only one (at VT) in which an opponent had an effective FG% (like FG%, but gives extra weight to made 3s) below 50%. Before that, Duke had allowed an opponent eFG% above 50% only 5 times in 21 games.
Of course you can't argue with the offensive numbers since the lineup change: in its last five games, Duke has turned the ball over on less than 15% of possessions, and shot 2 free throws for every field goal attempted. Both of those are phenomenal figures and well above Duke's season averages (yes it's a sample of only five games, but to put up those kind of numbers late in the season against quality competition is still very encouraging).

My own opinion is the decline in Duke's D has less to do with Williams and Scheyer than with Nolan Smith, who was tremendously effective pressuring the ball early in the year but fell off in mid January. I suspect this has more to do with Nolan's health than his game, but that is conjecture. But since I'm stating opinion at this point, I might as well say I don't think Duke will make a deep March run with the kind of defensive numbers they've put up recently. However, if Nolan Smith can get back to his early January form and Duke can use Williams and Smith interchangably and/or together to pressure the ball, I like Duke's chances.

I'm not yet near fluency in Pomerese, but isn't there a metric, maybe 'adjusted efg%' that takes possessions into account, i.e. even if your opponent is converting a high percentage of its actual attempts, there should be a stat that deflates that number if say, the team is turning the ball over a lot.

fogey
03-06-2009, 12:25 PM
Our defensive ratings are much more influenced by the quality of the opposition than to our lineup changes, in my view. Elliot is a terrific defender, and his minutes on the floor have certainly not hurt our defense. But the early season patsies are long gone, and it is much tougher to defend better teams successfully.

tbyers11
03-06-2009, 01:22 PM
I'm not yet near fluency in Pomerese, but isn't there a metric, maybe 'adjusted efg%' that takes possessions into account, i.e. even if your opponent is converting a high percentage of its actual attempts, there should be a stat that deflates that number if say, the team is turning the ball over a lot.

Here is Ken Pom's Duke Game Plan (http://kenpom.com/expsked.php?team=Duke) page and here is the explanation (http://kenpom.com/blog/index.php/weblog/stats_explained/) of what the column headings mean.

Defensive efficiency (Eff. under Defense) is the metric that I think addresses overall defense the best. It is points allowed/# of possessions. Anything below 100 in Pomeroyese is generally considered good. Anything below 90 is really good.

The four columns to the left (effective FG% (eFG%), turnover rate (TO%), offensive rebounds allowed rate (OR%) and free throws allowed rate (FTR) break down the defense into specific areas that can tell you more specifically why the team is excelling or failing at defense. TO% directly answers your question about by showing how of the opposing teams possessions become turnovers. While everyone wants to have as low an eFG% as possible just using that stat doesn't give you the whole defensive picture, TO%, OR% and FTR fill out that picture.

On Ken Pom's scouting report (http://kenpom.com/team.php?y=2009&team=Duke) for Duke you can look at the four factors for the defense (in the upper left) and see how Duke ranks amongst all DI teams. The data suggests that while Duke is good at eFG% defense (81st is still top 25% of all teams) is it is really good at forcing turnovers (20th best in D1).

Hope that helps a bit