Artest for Ariza?

Posted on July 7, 2009 by


Last week I attended the Western Economic Association meetings in Vancouver.  The North American Association of Sports Economists (via the efforts of Brad Humphreys, Tony Krautmann, and myself) organized fifteen sessions – consisting of more than 50 papers – on various topics within the field of sports economics.

On June 29th I flew into Vancouver, and along the way (while sitting in DIA) I wrote Detroit Refuses Rondo?  The meeting was held at the Sheraton Wall Centre in Vancouver and it took me a couple of days to figure out where I could get wireless access in the hotel (it was not available in my room).  While I was out of touch, though, this short post on Rajon Rondo attracted quite a few comments.  At this point, most of these I still have not read (hopefully no one has said anything that is overly offensive).  Although I didn’t find time to read these comments, I did squeeze out a little bit of time to post a short comment on Detroit’s signing of Ben Gordon and Charlie Villanueva.  

Now I am back in Cedar City.  It was my intention to post a longer comment on what was learned at these meetings, but I think that is going to have to wait until later in the week.  For now I want to offer a brief comment on the following table:

Table One: Comparing Ron Artest and Trevor Ariza

Essentially the Houston Rockets and LA Lakers have swapped these two small forwards.  The consensus seems to be that this move strengthens the Lakers.  Although I don’t think this move severely harms LA, I don’t see how it helps.  As Table One reports, last season Ariza was a more efficient scorer, was better at grabbing rebounds and steals, and was less likely to commit turnovers.  When we look at the past three seasons of Wins Produced and WP48 [Wins Produced per 48 minutes] we see the following:

Trevor Ariza:

2008-09: 8.0 Wins Produced, 0.192 WP48

2007-08: 2.6 Wins Produced, 0.225 WP48

2006-07: 5.8 Wins Produced, 0.217 WP48

Ron Artest:

2008-09: 4.2 Wins Produced, 0.083 WP48

2007-08: 4.5 Wins Produced, 0.100 WP48

2006-07: 8.9 Wins Produced, 0.161 WP48

The 2006-07 season was Artest’s most productive season [in terms of WP48].  Artest will turn 30 in November, so it seems unlikely that he is going to return to this peak.  Even if he did, Ariza has already surpassed this peak on three occasions.  Furthermore, Ariza is younger and apparently less prone to cause his organization distress.  So if this was a trade, it looks like the Rockets have come out ahead. 

Unfortunately, the standings might not tell this story at the end of the 2009-10 season.  The Rockets will probably struggle somewhat without Yao Ming.  And the Lakers will still be very good.  So it might appear that the conventional wisdom on this move will look okay.  But if we take the time to look past scoring, and separate a player from his teammates, the Rockets with Ariza look better today.  And that should still be the story in 2010.

Let me close by noting that July 8th is a big day in the NBA and there should be plenty of news.  But I am going to try and ignore these events and focus my next post on last week’s meetings and all that we learned in Vancouver.  That post, though, is going to have to wait until I catch-up at the office.

– DJ

The WoW Journal Comments Policy

Our research on the NBA was summarized HERE.

The Technical Notes at provides substantially more information on the published research behind Wins Produced and Win Score

Wins Produced, Win Score, and PAWSmin are also discussed in the following posts:

Simple Models of Player Performance

Wins Produced vs. Win Score

What Wins Produced Says and What It Does Not Say

Introducing PAWSmin — and a Defense of Box Score Statistics

Finally, A Guide to Evaluating Models contains useful hints on how to interpret and evaluate statistical models.