Wednesday, June 25, 2008

Last Blazers Post for a While

Alright, I was sitting down to drop a short draft preview and I saw something so wrong, so incongruous with my world view I had to mention it here. I just saw Bill O'Reilly, avowed conservative arguing for more regulation of a certain business. I'm still not sure what to say.

Anyway, draft day is tomorrow, and the 3rd annual pritch-slapping of the NBA has already begun. In case you haven't heard, the Blazers bought the 27th pick from New Orleans for cash consideration. This is the same kind of move that netted Portland the rights to supposed sensation Rudy Fernandez. I have a had few comments asking what I would like to see Portland do, and what I think is likely. Well, for all my thoughts are worth, here you go:

I still see Pritchard trying to move the 13th pick. I really don't see there being a player available that will be ready to step in and contribute in the way Portland really needs. Moreover, given the working plan (AKA the Cap-Space for 2009-10 Plan), Portland likely needs to move one or more of Frye, J Jack, and Webster. (For more detail see this site.) Based on that I think Pritchard is most likely to either trade up from 13, or trade for a player that fits Portland's needs.

What I would like to see: Of the three players mentioned I would prefer to see them keep Webster. I think at worst he is a legit 3-point threat that can open the floor a-la James Jones or Kyle Korver. If he continues to develop to his true potential, his ceiling is much much higher. That isn't to say I don't like Jack or Frye, I just think Webster is the more rare of the commodities. I am not as convinced as some that SF is a big need for Portland. I think Outlaw and Webster both have big potential at the 3. I am much more convinced that we need an improvement at the point. So, I guess I'm looking for Pritchard to try and pick up a quality point, but one that is comfortable without the ball. A good shooter, and a good defender with a good handle under pressure.

Other then that, given Pritchard's general MO of stocking talent, I expect to see a lot of BPA tommorrow. (And at least 2 more trades... but I am not plugged in enough to really speculate with who/for who.) I do like Heinrich a lot, but I am not a fan of contract, and that rumor seems to have died out.

Monday, June 23, 2008

Advanced Statistics and the Portland Trailblazers Pt. II

I was going to start writing this post a couple of days ago, but I had a little bit of trouble coming by the numbers that I needed. Pace and efficiency stats aren't too tough to come by, but the other numbers are. Well, they are in the form I wanted them in. (which is awesome for other reasons...) has the rebounding numbers, but only to 2 decimal places. To really compare across the whole league, the third decimal is important. So, I wound up building a spreadsheet and calculating the numbers by hand. That was before I found the table I was looking for on basketball-reference. I got lazy when it came to calculating league averages for pace and efficiency. I am sure you will cope. Well, with that out of the way, here are the numbers.

Portland League Rank League Leader League Worst League Average
Pace 89.7 29 99.7 (Denver) 87.3 (Detroit) Not Available
Offensive Efficiency 107.3 14 113.8 (Utah) 100.5 (Seattle) Not Available
Defensive Efficiency 108.4 17 98.9 (Boston 112.8 (Milwaukee) Not Available
eFG% 49.00% 16 55.2% (Phoenix) 44.3% (Miami) 49.30%
oReb% 26.70% 15 31.8% (Philadelphia) 22.1% (Miami) 26.70%
dReb% 71.80% 24 .783 (LA Clippers) 70.3% (Golden State) 73.40%
TO% 13.40% 7 11.4% (Toronto & Detroit) 16.5% (Boston) 13.00%
FT Rate 22.80% 21 27.6% (Sacramento) 18.3% (Minnesota) 23.20%

Alright, so there are the numbers. What do they mean? That is a good question. And it is a question that doesn't have an easy answer.

First, looking at pace we see something that I think we knew intuitively. Specifically Portland plays slow, deliberate basketball. Moreover, I don't see that changing a whole lot as long as B. Roy is around. But we also see that Portland is pretty efficient on the offensive end. And efficiency is the important thing.

The defensive end is another story. And, to further illustrate why pace independent statistics are important, if we look solely at opp points/game, Portland is 8th in the league. But once we take Portland snail like pace into account, we see that rather than in the top 1/3 of the league, the Blazers are really in the bottom half. I also think it is important to note that although Portland is near the middle of the league in Defensive Efficiency ranking wise, the distance between Portland and Milwaukee is pretty small.

The other two numbers that really jump out are defensive rebounding and FT Rate. I think most people recognized that Portland struggled on the defensive glass this year. This is an area Portland should look to improve on. With the addition of Oden in the middle, I am expecting some strong improvement here. A better dReb% should also help improve Defensive Efficiency. It is pretty easy to see the strength of keeping an opponent of the offensive glass.

I am less sure what to make the FT Rate numbers. Of the Four Factors, this one is generally regarded as the least important. Also, although ranked quite low, it appears there is a big bunch near the midpoint, and Portland isn't far from it. Looking at the numbers behind Portland's FT Rate, the Blazes made their foul shots at a good clip (about 76.6%), but really didn't get to the line that often. If Portland had gotten to the line as often as the league average, they would have scored almost 1.34 more points per game. Is that much of a difference? It is worth about 4 wins under the basketball Pythagorean formula*. I would say that is fairly significant.

So, did any of this really communicate information that wasn't clear to somebody just watching the season? I am sure some of it was clear. But if you didn't dig into these numbers, you may think that Portland didn't have much trouble on defense, or that the lack of defensive rebounding wasn't particularly crucial. Either of those beliefs could lead to bad moves as it comes time to build the team for next year.

*In case you are not familiar with it, one of the first big advances in sports statistical research was the so called Pythagorean Theorem of Baseball, or Pythagorean Records. It seems almost a truism to say that your win/lose record is going to be determined by the number of runs(or points) you score and the number you give up. However, a little research showed that a teams winning percentage in baseball is closely tied to: runs scored^2/(runs scored^2 + runs allowed^2). It turns out if we tweak the exponent a little we get an even better fit. The same can be said for NBA Basketball. The generally agreed upon formula for basketball is: Pythagorean Expectation % = Tm pts^14/(Tm pts^14+Opp pts^14).

It should be noted that Portland exceeded it's Pythagorean Expectation this year by about 3 wins. Anecdotally it would seem this would be due to performing better then expected in close games, and losing a few more blow-outs then they won. I haven't taken the time to examine this, and I won't now as this post is getting a bit long.

Tuesday, June 17, 2008

Modern Basketball Statistics and the Portland Trailblazers (Part 1)

So, those of you that have had more than a beer or two with me lately know that for the last year or so I have become intrigued with the so called sabremetrics (or statistical) approach to looking at baseball performances. My interest in this topic has been fired by the Seattle Mariners blog community. It turns out that the two biggest blogs covering the Mariners both take a decidedly statistical approach to analyzing baseball performances. From there I started thinking about and looking into what work has been done in this realm for other sports. This post is a discussion of the new thinking as it applies to the Portland Trailblazers.

Before discussing where the Blazers are and where they could be going, it would be helpful to give a basic description of what new statistics I am talking about and why things like points per game should become obsolete in the near future much as ERA has.

Some of the my favorite work to date has been done looking at offensive and defensive efficiency. The concept is this: Basic statistics measure how many points a team scores and how many points a team gives up. But, these numbers doesn't exist in a vacuum, and teams that score fewer points don't necessarily have worse offenses. If a team is more deliberate in it's offense, if it uses more of the shot clock each trip down the floor, that team will have fewer overall possessions then a team that shots quickly (like the Suns of the last couple of years). Even a team that is efficient in terms of how it uses it's possessions may score fewer points in a game than a less efficient, but faster team.

Since a game is of a defined length (48 minutes in the NBA) it isn't too difficult to calculate the number of possessions per game a team gets (See here: for the formula)* Once we know how many possessions a team has in an average game we can look at how many points per possession a team generates. Although this could be a useful measure, most sites extrapolate out to points scored per 100 possessions to compare across teams. This is useful not just to see how efficient an offense is, but it can also be used as a measure of team defense. Looking at offensive and defensive efficiency will give you a basic measure of a teams health.

Although there are other advanced statistics that bear discussion, today I am going to talk about The Four Factors. This is a concept advanced by Dean Oliver in his book Basketball on Paper. Now, this discussion should come with the caveat that I haven't read that book yet. As such, this discussion will be somewhat cursory. The idea is that a basketball game can be broken down into (shocked face) Four Factors:

  1. Shooting

  2. Rebounding

  3. Ball handling

  4. Getting to the free throw line.

This may sound a little simplistic, but it should be noted his work was good enough to get him a job with the Seattle Supersonics and the Denver Nuggets as a full time statistical analyst. Since I am starting to run out of time, tonight I will cover the basics of the four factors and the simple, but more useful statistic.

1) Shooting

When talking about shooting, normal FG% isn't enough. Specifically it fails to account for the added importance of a 3 point field goal. Since a three is worth 50% more than a two, we need to use a waited percentage. This number is generally referred to as “effective field goal percentage” or eFG%. Simply put eFG = (fgm + .5*3fgm)/fga.

2) Rebounding

Once again per game stats are insufficient to measure how well a team does. Per game stats don't account for the number of rebounds that are available in a given game. The better measure is offensive and defensive rebounding percentage. These numbers are fairly self explanatory.

OReb% = OReb / (OReb + Opp DReb)

DReb% = DReb / (DReb + Opp OReb)

3) Ball Handling

Rather then just looking at pure turnovers per game, we can use a possession based statistic: Turnover % = Turnovers / Possession.

4) Free Throws

This one is a little more strange. Although we could just look at FTA or FTM, its always better to take into account the pace of the team you are talking about. Most researchers look at FTM/FGA and dub this “free throw rate”.

None of these stats is the be all end all, and all statistics can be effected by factors that aren't necessarily what we are trying to measure. Alright, it is getting late tonight. Sometime tomorrow or later this week I will drop a post discussing what these numbers say about Portland and where they need to improve.

*Basketball reference is an awesome site. If you like basketball and/or statistics, it is a site you can lose a lot of time at. Their formula is quite good, but also a bit complex. If you need a short version FGA + TO + ~.5 FTA – ORB will get you close, but it isn't particularly exact.