Last season during the playoffs, I ran a regular column here at SS&R titled Tempo-Free Boxscore Breakdown. In it I used a toolkit of unorthodox statistical measures to take apart the Lakers performance game by game. The idea was that by looking at game stats in a different light - in particular, by analyzing the numbers per individual team possession, rather than per game - we might learn things about how the Lakers play that you can't glean from the conventional newspaper box score.
TFBB is back this year, slightly reworked. It won't run for every game during the regular season, but we'll do one for each of the life-and-death contests (Boston, Cleveland, a couple other opponents) as well as weekly pieces looking at stat trends as they develop over the season. And don't worry: when we get to the playoffs, we'll resume our usual every-game dissection of the numbers. (I know you were worried!)
The other change is the name. Tempo-Free Boxscore Breakdown, let's be honest, is the most boring name given to anything ever. I should know, I came up with it. Sorry to have inflicted it on you last spring. To inject some much-needed heat and passion, I've renamed the column Laker Stats Orgy. It's shorter and punchier and I hope will trick search-engine users who type in the word "orgy."
I can tell you're excited, so let's throw some plastic over the furniture and get going. Bow chicka bow-wow.
For Issue #01 of LSO, I'm not going to look at any numbers from the season so far. We're only seven games in, which is an awfully small sample size. There's not much point in trying to extract meaning. Instead, I'm going to begin at the beginning, introducing the basic terminology. What follow are the definitions of the measures that we use, a brief explanation of why we use them and, for context, how the Lakers performed in each one last season.
There's nothing here that we invented ourselves, and it's not nearly as math-intensive as it might look. I suck at math and still do this stuff, so clearly anyone can.
Possessions: The possession is the basic unit of currency here. A possession begins when a team gets control of the ball and ends when the other team takes over control. A possession can end with a made shot or free throw, a turnover or the end of a period. If a team misses a shot, gets the rebound, misses again, gets the rebound again and finally makes a field goal, that's still all one possession.
Given how basketball works - teams alternate possession, back and forth, until time runs out - a team and its opponent will always have an equal or nearly equal number of possessions in a game. Barring overtime, one team can never finish a game with more than two possessions more than its opponent, and that only occurs if one team has the final possession in all four quarters.
The idea behind counting possessions is to separate performance from pace. Some teams (for instance, the Knicks) play much faster than others (for instance, the Cavaliers). Their up-and-down style inflates the number of points they both score and allow in each game. Looking only at per-game stats thus distorts a team's underlying efficiency on both offense and defense.
Pace: This means the average number of possessions a team and its opponents get per 48 minutes of play. Last season the league-average pace was between 90 and 91. The 2008-09 Lakers had a pace of 93.0, which was the sixth highest in the NBA.
Looking at a typical box score, you can estimate the number of possessions in a game with the following formula:
0.96 x (FGA + (0.44 x FTA)) - Offensive Rebounds + Turnovers)
This will usually get you within one or two possessions of the exact number. Because we at SS&R are committed to the highest standards of customer service, however, for Laker games I tally up possessions one by one the hard way. Yes, I am a hero. It's true.
Points Per Possession (PPP): Just what it sounds like, the number of points (scored or allowed) divided by the number of possessions used. An average possession in the NBA last year resulted in 1.10 points scored. The 2008-09 Lakers scored 1.145 points per possession (third best in the NBA) and allowed 1.061 points per possession (fifth best in the NBA).
Offensive Rating: Points scored per 100 possessions. Just take your offensive PPP and multiply it by 100.
I prefer PPP to Offensive Rating because the former is less jargony and more straightforward about what it describes, but I'm in the minority about this. Those who prefer Offensive Rating like that it gets us out of the realm of really small numbers and that 100 possessions is in the neighborhood of what you see in a typical NBA game. Because the hoops analyst community generally uses Offensive Rating instead of PPP, we use it occasion too, but in any event the two terms are describing the same thing.
Defensive Rating: Points allowed per 100 possessions.
Turnover Rate: The portion of a team's offensive possessions that end in a turnover. About 16% of possessions end in turnovers in the NBA. Last year the Lakers had an offensive turnover rate of 14.2%, good for fifth in the league, and their "defensive turnover rate" (or the turnover rate of their opponents) was 16.6%, good for sixth in the league.
FTA/FGA: The ratio of a team's free-throw attempts to its field-goal attempts. This measures a team's ability to draw fouls and get to the free-throw line and to prevent its opponent from doing the same. We use it instead of "free throw margin," which simply compares a team's raw free-throw attempts to those of its opponents, to remove the effects of pace and turnovers.
Pace is an issue that we've already covered: an up-and-down team will both accumulate and allow more free-throw attempts than it would otherwise. Turnovers have similar potential to distort. If one team has fewer free-throw attempts than its opponent, it could be simply because more of its possessions are ending in turnovers, before it can get a shot off. Thus we use FTA/FGA to zero in on what portion of a team's "looks at the basket" result in a trip to the charity stripe.
Last year the league-average FTA/FGA was 0.306. On offense the Lakers had a ratio of 0.230, ranking 20th in the NBA, and they allowed opponents a ratio of 0.213, sixth in the NBA.
FT%: This isn't an advanced metric. It's just free-throw percentage. I mention it here because at other sites you might sometimes see the ratio FTM/FGA (free throws made to field goals attempted) instead of FTA/FGA, discussed above. In my view, that conflates two separate skills: getting to the line and making free throws once you're there. Think of Shaq, a player great at drawing free throw attempts and terrible at converting them.
Last year the Lakers made 77.0% of their free throws, almost exactly league average. Laker opponents made only 75.3% of their free throws, second lowest rate in the NBA.
Effective Field-Goal Percentage (EFG): This is a mildly tweaked version of traditional field-goal percentage. It's calculated the same way but counts each three-pointer made as 1.5 field goals, to reflect its added value. In last night's game against the Hornets, for example, the Lakers shot 38 for 81 from the field, including 12 for 27 on three point attempts. Each of those 12 three pointers gets an extra 0.5 value, so to calculate the Lakers' EFG we just divide 44 (or 38 plus 6) by 81, to get 54%.
Last year the league-average EFG was almost exactly 50%. The Lakers' EFG was 51.3%, sixth highest in the NBA, and they allowed opponents to shoot an EFG of 49.0%, eighth lowest in the NBA.
True Shooting Percentage (TS%) is a bit more complicated, but only a bit. It's a measure of shooting efficiency that takes into account not only the added value of three-pointers but both free-throw attempts and makes. As Pro Basketball Prospectus puts it, "TS% can be thought of as what a player's field-goal percentage would be if they maintained the same level of efficiency while only shooting two-pointers." True Shooting blends three of the measures discussed above: Effective Field-Goal Percentage, FTA/FGA and free-throw shooting accuracy.
The formula for calculating TS% is points scored divided by two times "shooting possessions," which equal (FGA + (0.44 x FTA)). If you're wondering about the 0.44, and in particular why it's not 0.50, it's because not all trips to the free-throw line burn a possession. Some free throws come from "and 1s" and others from technical fouls. The 0.44 coefficient has been arrived at through trial and error as a sound way of estimating the number of possessions actually used by free-throw attempts.
The league last year had an average True Shooting Percentage of 54.4%. The Lakers' TS% was 55.7%, seventh best in the league, and they allowed opponents a TS% of 53.0%, sixth best in the league.
Offensive Rebounding Rate: The portion of a team's offensive rebounding opportunities (consisting of its missed FGAs and certain of its missed FTAs) that are actually collected as offensive rebounds.
Defensive Rebounding Rate has a corollary definition. It means the portion of a team's defensive rebounding opportunities that are actually collected as defensive rebounds.
Defensive rebounding is easier than offensive rebounding. On average, only about 27% of missed shots lead to offensive rebounds, so the standard rebounding stat, "rebounding margin," is distorted by shooting accuracy. Imagine, for example, a game in which the Lakers are ice cold from the field while their opponents are filling it up. The opponent is likely to collect rebounds in greater raw numbers simply because they have many more defensive rebounds to collect. It doesn't necessarily mean that the Lakers are doing a bad job of rebounding.
Accordingly, we break rebounding performance into offensive and defensive rates instead. Last year the Lakers had an offensive rebounding rate of 29%, good for third in the NBA, and a defensive rebounding rate of 73%, which ranked 19th.
And with that, the orgy is underway! If you're still reading, you should be either extremely proud of yourself or moderately ashamed, I can't decide which. I promise, in any case, that future editions of the LSO won't be quite this wonky. Just thought it would be useful to get this all in one place for everyone's present and future reference. Thanks for your patience, and for just being you.