Team Efficiency Ratings - 2005-2006 Regular Season

Hi Folks:

I'm working on a little project to do some new analysis. What I want to do is some team efficiency analysis trending over the course of the past season to analyze the Rockets performance using offensive and defensive efficiency metrics. What I want to do is analyze how we stacked up against the league and how our new additions might (or might not) improve us next season.

In setting that up, I've been putting some preliminary stats together using some offensive and defensive efficiency statistics for all the teams in the NBA for 05-06 regular season. I thought I would post some of these base stats for discussion.

Here's a quick legend for some of the figures in the tables to follow:
ps- points scored
fg- field goals made
fga- field goal attempts
pospg- possession per game
ppp- points per 100 possessions (explanation to come)
sp- scoring possesions (number of possesions resulting in a score)
floor%- (explanation to come)

For the following tables I've bolded in RED the stat I'm sorting on for a particular table. For discussion purposes I've also highlighted the Rockets, Mavericks, and Heat to serve as reference points.

Points Per 100 Possessions (ppp) is an interesting stat that is intended to gauge how efficient an offense is by removing the pace of the game out of the equation. "To get a true evaluation of each team’s offense and defense, it’s much more revealing to look at scoring per possession, because the per-game values are corrupted by the pace that each team played."

Here's a link with more discussion regarding PPP:
http://kenpom.com/blog/index.php/weblog/stats_explained/

NBA 05-06 Efficiency Ratings - Sorted By Offensive PPP:


Looking at the offensive PPP ratings, nothing really stands out to me that we already didn't know about the Rockets. Next to last in offensive efficiency at a dismal 100.1 (league avg. 104.4).

NBA 05-06 Efficiency Ratings - Sorted By Defensive PPP:


This was of interest to me. Purely on points allowed the Rockets rank #4 while looking at defensive PPP we're ranked #7. What was of more interest to me were the different teams that were in the 1-8 spots. I expected to see the usual suspects of what we typically think of as strong defensive teams but found the list a little unusual.

Of even more interest was where Miami and Dallas fell. I expected to see them higher up the list.

Another measure of offensive efficiency is the concept of Floor %. Floor % is basically the % that a team scores out of it's total possessions it has. In other words it's how effective a team is in converting a possession into a score. It's different from field goal percentage, but rather it takes into account how effectively a team converts possessions into field goals or free throws.

NBA 05-06 Efficiency Ratings - Sorted by Offensive Floor %:


NBA 05-06 Efficiency Ratings - Sorted by Defensive Floor %:


These two tables were of interest to me. What obviously stood out to me was that Dallas and Miami were the most efficient teams last season in converting possessions into points.

What also struck me was where they were in relationship to defensive floor % compared to the rest of the league.

One of the conclusions I'm drawing from all of this is that perhaps defense if overrated- not that it isn't important, but rather that it's not as equally important as having an efficienty offense that is able to give you a higher probability to scoring out of every possession.

There's probably a lot more to chew on here. I'd thought I would put this stuff out there for people to mull over. Meanwhile, I'll get back to working on my other analysis that'll make use of some of this info! Cheers!

 

Yes it does. Here's the gory formula ...

Sc.Poss = FG+0.4*FTA*(FT%*FT%+2*FT%*(1-FT%))

You then take the above and divide it by the total possessions (yet another derived value from a formula).

Just for clarity PPP takes into account actual points scored. Floor% only looks at FG's and FT's made and doesn't make a distinction between a 2 or 3 ptr.

 

That's what the .4 factor is there for. You'll have to go look up how some of the stats wizards arrived at that which is supposed to account for and-1's, otherwise it would be a .5 factor.

 

I think my statement is misleading. I'm actually more of the "balanced" camp meaning you need both. I think what you described regarding how much balance is what I was trying to draw distinction to. What I was meaning to say is that the balance might not quite be 50/50, but 60/40 weighted toward offense.

 

To be honest, that's part of the reason I'm doing the analysis. Folks say this and they also point to the fact that with both Tracy and Yao in the mix we were doing well with last year's team.

Here's one of the reason's I think there's more to the story. Here's a graph I had put together in the early spring. I didn't go back and fill in the rest of the season. The graph was made up to the point we lost TMac.



The thing to note is the strength of schedule trend (purple line). TMac and Yao were back together around the 41 game mark and that's when we seemed to start turning things around. What's disturbing though is that was really in a very weak part of the season for the Rockets. Most of the teams we played were under .500 during that stretch. (Ignore the green line - it's a little off but it's supposed to be where .500 is).

 

I don't know that you choose one over the other per se. At least I'm not advocating that. I think you look at both. Just to clarify - floor% isn't "how often you can score" but how efficient you are at scoring with each possession.

freemaniam- you have a point. If you look at the floor% off & def it's pretty close in terms of which teams are in the playoffs vs. not. Actually what I haven't done yet is to adjust the PPP's or the Floor% against strength of schedule which might yield some other insights.