Pelton mailbag: How special were NBA superstars this season?

Kevin Pelton answers your questions in his weekly NBA mailbag. AP Photo/David J. Phillip

This week's mailbag features your questions on Robin Lopez balling against teams without mascots, home-court advantage in the playoffs, and more.

You can tweet your questions using the hashtag #peltonmailbag or email them to peltonmailbag@gmail.com.

During Game 2 of the Chicago Bulls' series with the Boston Celtics, mascot enthusiast and ESPN writer Zach Lowe attributed Robin Lopez's successful play in this series (he's got 32 points on 14-of-20 shooting and 18 rebounds through two games) to the Celtics' lack of a traditional mascot. (Boston is the only NBA team that instead uses a human mascot, Lucky the Leprechaun.)

Naturally, this got me thinking about a study. Including the Celtics, there are five teams without a traditional mascot: the Brooklyn Nets (who retired the BrooklyKnight in 2014 after just two seasons), the Golden State Warriors (who retired their mascot, Thunder, after Oklahoma City adopted the nickname), the Los Angeles Lakers and the New York Knicks.

Lo and behold, Lopez has dominated those teams this season. His best game score per 36 minutes, using John Hollinger's measure of single-game play, came against the Celtics and the Lakers, with the Nets and Warriors also in the top six. Even after we account for these teams have tended to play worse against centers (based on HoopsStats.com's breakdown of box-score stats by opponent position), Lopez still performed at 92 percent of the average center's game score per 36 minutes against the five teams without mascots, as compared to 77 percent against all other teams.

Sadly, odds are this is just a fluke. During 2015-16, while playing for the Knicks, Lopez played no better against the other four mascot-less teams than the rest of the league. Still, I prefer to believe that Lopez would be a dominant center if he weren't so distracted by mascots.

"People like to talk about "great home crowds" tipping the balance in a playoff series. I've heard you say before that only Denver and Utah (because of the altitude) actually have a better home-court advantage in the regular season -- everyone else's home-court advantage basically the same. Does that change in the postseason?" -- Milo Phillips-Brown

I went back to 2003, which was the year the first round expanded to a best-of-seven format, and looked at how teams performed at home versus on the road relative to their point differential and the opponent's during the regular season (not including this season). The team with the biggest playoff home-court advantage? The Seattle SuperSonics, who were 8.0 points better than expected at home and 6.9 points worse on the road. Alas, that sample is pretty small, covering only the two playoff series the Sonics played in 2005 (going 5-1 at home and 1-4 on the road).

While most other sample sizes are a little bigger, when you account for them the data generally shows the same thing as in the regular season. Most of the differences among teams in home-court advantage are probably attributable to randomness. Here are the top and bottom teams, along with their z-score, or the number of standard deviations (SD) by which their observed home-court advantage differs from the average among all teams.

The vast majority of the observed home-court advantages fall within one standard deviation of league average, which is what you'd expect just by pure random chance. Only one team (the Bulls, with a worse home-court advantage than usual) falls more than two standard deviations from league average. But with 32 teams (counting the Sonics and Thunder and Brooklyn and New Jersey Nets separately), we'd expect one to differ this much from average by random chance too. (This is known as the Wyatt Earp effect.)

So while home-court advantage definitely goes up during the playoffs (the difference between home and road averaged about 8.8 points per game, even after accounting for the strengths of the teams), the sample of games isn't big enough for us to really distinguish any individual team's home-court advantage from league average.

"Did you realize DeAndre Jordan missed being the first man to increase his scoring average eight years in a row by TWO POINTS? He needed 20 points in the last game and had 18 with over eight minutes to play. The Clippers were pretty much in control of the game the rest of the way, but he took no more shots. Didn't anybody tell Doc (or Chris Paul)? As somebody who loves quirky stats like that, it bummed me out. Oh well ... at least Giannis finished top-20 (actually, top-18) in the five major categories!" -- Sam

You'll recall that Jordan's streak came up in a February mailbag in the context of Gordon Hayward increasing his scoring average for a sixth consecutive season. I noted then that Jordan was one of three players with seven-year streaks and had a chance at becoming the first to eight.

I know somebody in the LA Clippers' organization was aware of the streak because the broadcast team of Ralph Lawler and Michael Smith mentioned it on the air. But if Jordan knew how many points he needed, he certainly didn't show it. I'd like to believe that teammate JJ Redick wanted to keep Jordan at seven as one of the players currently tied for the longest streak (Derek Harper is the other since the ABA-NBA merger) ... but, alas, Redick never took the court in the fourth quarter.

"Has Rajon Rondo already won the Nelson Valdez award for player to most improve his reputation with his team's fan base for these playoffs? Or are there any other candidates that may pull it out by the end?" -- Mike Beight

For readers who aren't MLS fans, Valdez was a disappointment in a season and a half as the Seattle Sounders' high-paid designated player ... until he started scoring goals like crazy during the team's unlikely run to win last year's MLS Cup.

While skeptical Bulls fans will be harder to win over, I think Rondo has to be the heavy favorite for this award. In fact, other than maybe his teammate Dwyane Wade, I can't think of anyone else who would really be a contender at this point.

"Is this season special for individual greatness? In terms of catch-all advanced stats, it doesn't seem to be special. But is there a gap between what those catch-all stats are telling us and something real that the public perceives, and if so, what can explain that gap?

"Between Russell Westbrook's triple-double, James Harden's offensive prowess, LeBron James' career highs in RPG and APG, Giannis leading his team in the "big five" box-score-counting stats, this season certainly feels like a unique season for individual greatness.

"Yet as you noted in your MVP analysis, this is a down season for win shares. RPM seems down too, with Chris Paul's and James' leading RPMs significantly below the leaders of previous years available on ESPN. You noted that Westbrook 'broke' BPM, and after him, only Harden begins to compare in a historical context. Westbrook's PER -- my least favorite stat -- is impressive. And his WARP isn't that bullish on Westbrook, historically.

"What factors account for the discrepancy between our perception of historical greatness and the lack there of as told by advanced stats?" -- Izzy Gainsburg

Great question by Izzy, and one I'd wanted to address in the piece he references but didn't have room to discuss. Pace is certainly one factor. When we compare James' 2016-17 to his prime years in Cleveland and Miami, for example, we have to account for the fact that pace is 4.6 possessions per game faster than it was in 2008-09. But it's still not nearly as fast as during the entire 1980s, so that doesn't entirely explain the discrepancy.

Improved offensive efficiency is a better explanation. As Lowe predicted midway through the season, the NBA smashed the record with a 106.2 offensive rating, nearly a point per 100 possessions better than the previous high-water mark of 105.4. Since everyone was scoring more efficiently, the combination of volume and efficiency we saw from superstars this season wasn't quite as historic as it appeared without adjusting for league average.

The third key factor would be turnovers. Harden and Westbrook both demolished the record Harden previously held for turnovers in a single season, and James set a new career high in the category. Oftentimes, when discussing offensive efficiency, we have a tendency to focus on true shooting percentage and ignore that turnovers are part of efficiency, too.

Together, I think those three factors go a long way toward explaining why this season's MVP race wasn't as historic in terms of the statistical value of the players involved as it felt from their box-score stats.