Trevor Ariza's Efficiency Has Plummeted in HoustonSome misinformed "stat gurus" insist that basketball can best be understood without even watching any games, because the eyes are supposedly biased but the numbers are supposedly completely objective. The "stat gurus" declare that a player's productivity is not significantly impacted by his minutes played or by who his teammates are--he is who he is regardless of his environment. For instance, several years ago I (futilely) tried to convince a "stat guru" that Gary Payton did not fit in well with Phil Jackson's Triangle Offense; the "stat guru" insisted that on a per touch basis Payton did exactly the same things in the 2003-04 season as a Laker that he had done throughout his career, even though anyone who has even an ounce of common sense could easily see that Payton neither did the same things nor was he even remotely close to being as effective as he had been earlier in his career. Similarly, Ron Harper struggled initially to fit in with the Triangle Offense when he first signed with Jackson's Chicago Bulls but Harper eventually adjusted to being a role player within the structure of that offense (as opposed to being a 20-plus ppg scorer in other offensive systems previously).
Based on the same kind of erroneous thinking that the above "stat guru" applied to Payton, the Houston Rockets essentially swapped Ron Artest--the 2004 NBA Defensive Player of the Year and a four-time member of the All-Defensive First or Second Team--for Trevor Ariza, a role player who started for the Lakers' 2009 championship team. The Rockets' brain trust believed that Ariza--who clearly benefited from playing alongside Kobe Bryant last season--could emerge as a star in Houston.
Ariza only averaged more than 20 mpg once in his first four seasons. During that time, he displayed little ability to shoot the ball (3FG% of .278 or lower each year, FT% of .695 or lower each year) or to create a shot for himself or others; he served primarily as an athletic, energetic role player who could finish very well at the rim and play solid defense against perimeter players. Then in 2008-09 he played in all 82 games for the first time in his career, logging a career-high 20 regular season starts--including the final 19 games of the season. Ariza also started all 23 playoff games as the Lakers won the NBA Championship. Although his free throw shooting was still subpar at best (.710 FT% in the regular season, .563 FT% in the playoffs), he improved his three point shooting stroke (.319 3FG% in the regular season, .476 3FG% in the playoffs), an upgrade which is directly attributable to Bryant not only because Bryant drew so many defenders that Ariza had wide open looks but also because Bryant provided Ariza with an offseason program specifically geared to making someone a better three point shooter. Presumably, the technical improvements that Ariza made to his shooting stroke should survive being separated from Bryant but Ariza is still a player who struggles to create a shot for himself or others; he is best suited to be a team's fourth or fifth offensive option, not to lead a team in field goal attempts and/or scoring. Consequently, Ariza will be much more efficient in the role that he played last year in L.A. than if he is expected to be the focal point of a team's offense.
Essentially, a "stat guru" looks at Ariza's career year in 2008-09, factors in that Ariza is only 24 years old and projects that Ariza could be an All-Star if he simply played more minutes and got more touches. In contrast, after the de facto Artest-Ariza swap I wrote that in Houston Ariza will most likely remain a solid role player as opposed to developing into a star. I made that conclusion based on analyzing Ariza's skill set, as I described above; I understand that Ariza's 2008-09 productivity is a result of him playing alongside Bryant and that if Ariza's minutes/touches/role are increased he is unlikely to be able to maintain the same efficiency level.
There is still a long way to go in the 2009-10 season but here are the preliminary results of Houston's Ariza experiment: he has started all 14 games for the Rockets, is averaging a career-high 38.6 mpg and is leading the team in scoring (18.3 ppg) and field goal attempts. Do these numbers vindicate the "stat guru" perspective? As Lee Corso loves to say, "Not so fast my friend." Let's look at the whole picture. Ariza is shooting a career-low .388 from the field, though his three point shooting is solid (.343). On a per minute basis, Ariza is averaging a career-low in rebounds and a career-high in turnovers. Ariza's assist numbers are up--on both a per game and per minute basis--but I suspect that this is a result of a small sample size; Ariza had five or more assists in five of Houston's first nine games but he has had four or fewer assists in each of Houston's last five games. Similarly, even though Ariza's overall 3FG% is good the numbers are trending downward at an alarming pace: he made 11 of his first 21 three pointers (.524) but has shot just 23-78 (.294) from long range since then.
The Rockets have increased Ariza's minutes and field goal attempts but instead of "A Star is Born" we are witnessing "A Role Player is Overworked." Ariza averaged 23.3 ppg while shooting .500 from the field (including the aforementioned .524 from three point range) in his first three games as a Rocket but he has averaged 16.9 ppg on .361 field goal shooting (69-191) since that time. Many NBA players are capable of averaging 15-18 ppg if they have the opportunity to fire up enough shots but that does not make them stars. Look for Ariza's field goal percentage, three point field goal percentage and assist numbers to continue to drop as long as the Rockets depend on him to be their primary offensive option--but if stars Tracy McGrady and/or Yao Ming return to action and Ariza is able to resume being a 20 mpg role player then Ariza's scoring average will decline but his shooting percentages will bounce back somewhat.
posted by David Friedman @ 3:13 PM