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One of the most famous duos is that of Shaq and Kobe. They powered the Lakers back to prominence. The fact that personal issues shoved Shaq out a few years to early is one of the many pains felt by Laker fans, especially as Shaq would win a ring with another dynamic shooting guard in 2006. Except, the contributions of both Shaq and Kobe are overstated, by a lot! Let’s go back through our the Phil Jackson Laker titles and show what I mean.

The 2000 Lakers

Regular season
Player % of Lakers’ regular season wins
Shaquille O’Neal 32% (1st)
Kobe Bryant 16% (2nd)

Playoffs
Player % of Lakers’ playoff wins
Shaquille O’Neal 40% (1st)
Ron Harper 11% (2nd)
Robert Horry 10% (3rd)
Brian Shaw 8% (tied 4th)
A.C. Green 8% (tied 4th)
Glen Rice 8% (tied 4th)
Kobe Bryant 8% (tied 4th)

I’ve listed all players that put up more wins that Kobe and Shaq in either the regular season or the playoffs. In the regular season the start of the Lakers Kobe-Shaq dynasty was indeed the Kobe and Shaq show. Of course, Shaq was much better than Kobe and Kobe was pretty good himself. The playoffs were a different story. While Shaq kept up his insane play, Kobe dropped from being the second best player on the team and dropped below the likes of Ron Harper and Robert Horry in terms of helping the team win. And it’s worth noting that Kobe’s playoff production was actually below average!

The 2001 Lakers

Regular Season
Player % of Lakers’ regular season wins
Shaquille O’Neal 28% (1st)
Kobe Bryant 17% (2nd)

Playoffs
Player % of Lakers’ playoff wins
Kobe Bryant 20% (1st)
Derek Fisher 19% (2nd)
Shaquille O’Neal 17% (3rd)

The regular season dynamic kept up. Shaq shouldered most of the load. Kobe was a solid second. We do notice that Shaq slipped a little from his prior dominance. The playoffs is where we have to adjust our dials. Kobe was the best Laker on route to their back to back. However, Derek Fisher outplayed Shaq! Read that again. In Shaq’s second title, his performance was below Derek Fisher’s! And Derek Fisher definitely showed an amazing difference. In the 2001 regular season, Fisher was average. In the playoffs? He played over twice as good as an average player! The reason is surprisingly simple. Fisher shot over 50% from beyond the arc and had a true shooting of almost 70% for the whole playoffs! While Shaq certainly can take credit for getting the Lakers to the playoffs and definitely contributed to their second playoff run, Bryant and Fisher were the top dogs this go around.

2002

Regular season
Player % of Lakers’ regular season wins
Shaquille O’Neal 20% (1st)
Kobe Bryant 19% (2nd)

Playoffs
Player % of Lakers’ playoff wins
Robert Horry 30% (1st)
Shaquille O’Neal 24% (2nd)
Rick Fox 15% (3rd)
Kobe Bryant 12% (4th)

Robert Horry! You read that right. Robert Horry overall strong production anchored the final run for Shaq and Kobe. Shaq was still a strong contributor but not top dog. And while he was top four in total wins, it turns out that Kobe’s playoff production was again below average!
Summing Up

If we merely examine the regular season of the Lakers during the Kobe-Shaq era then a very familiar narrative is told. Shaq was an amazing player and Kobe was an excellent sidekick. As the years went on, Shaq declined and Kobe improved until their sad inevitable breakup. But, we know the playoffs are the irrational test we use to define greatness. And here is where the Shaq and Kobe myth crumbles. Shaq was only the top Laker in one of the Lakers’ three titles. Kobe was only a solid contributor in one of the three runs. To be fair, he was the best Laker in that run. And the “role players” of Fisher, Horry and Fox? Yeah, it turns out they were huge “when it mattered”. I can’t tell you how hilarious that is to write. The key we should all note is that the playoffs are very limited number of games. Over 20 games any NBA player can have a great run. Even greats can slump. The playoffs are a great place to find narratives, but may not be the best place to find statistical absolutes. And all I can say is when we examine the Shaq and Kobe playoffs narrative? Well, the numbers don’t back it up.

Beyond the fact that WP is not a good stat in general (poor predictive value), the WoW guys and their often overzealous followers do not take criticism well. They claim that their stat is highly predictive, but when called to prove this they hark either to its correlation with past wins, which is not prediction! - and which as ATC points out above is a given considering their framework, no matter how they weight different box score numbers, or they hark to the fact that player per-minute values for box-score numbers are pretty consistent year to year, but this does nothing to validate the values of their coefficients, but somehow they are convinced it does, and they have managed to convince a large following that this is the case.

It is clear from much of their work, even that of Berri, that they don't have a strong understanding of statistical mathematics, or robust model building, or proper inference techniques - which would be fine if they didn't act as if they wrote the book on regression analysis. They also apply their interesting view on statistics to debunking other attempts to model the NBA, often accusing others of making assumptions or using intuition, yet they cannot see (or refuse to acknowledge) that there is an enormous (and clearly flawed) leap of faith in assuming that a deconstruction of the team-efficiency equation with a few explanatory, non-predictive regressions thrown in, all done at the team level, is enough to best explain player value using the box-score.

The difference is that REBO no longer shows up in the formula. Now, if a player attempts a shot that is offensive rebounded, it does not contribute at all to PE. So, the player isn't penalized and the offensive rebounder isn't credited. Now, I wouldn't say that's fair, but then I don't think its fair to say that a missed field goal is equivalent to a turnover and an offensive rebound is equivalent to stealing it back. And that's effectively what the WP model says simply because of the way they formulate PE/PA, which is, I think, arbitrary on their part.

Beyond the fact that WP is not a good stat in general (poor predictive value), the WoW guys and their often overzealous followers do not take criticism well. They claim that their stat is highly predictive, but when called to prove this they hark either to its correlation with past wins, which is not prediction! - and which as ATC points out above is a given considering their framework, no matter how they weight different box score numbers, or they hark to the fact that player per-minute values for box-score numbers are pretty consistent year to year, but this does nothing to validate the values of their coefficients, but somehow they are convinced it does, and they have managed to convince a large following that this is the case.

All I could find in assessing WP's predictive value was Dan Rosenbaum's presentation of his paper "The Pot Calling the Kettle Black" at NESSIS (2007). Wish the actual paper was available somewhere. Dan used to have it on his website years back, but its no more to be found. Berri wrote a response to some of the points brought up by him, but it wasn't very substantive. I'm surprised the WoW analysts haven't written anything comparing the predictive power of WP to other stats.

We need a better study on this, but here is one that looked at out of sample (though it didn't filter to only focus on new lineups/changes, which would be more informative): http://sportskeptic.wordpress.com/2012/ ... the-goods/