Analytics 101 – Beyond the Boxscore – Offense

The world evolves and as such the decision process must evolve as well. There was a time when points, rebounds and assists were the overriding measure of an NBA player’s effectiveness. We are going to dive into the basics of advanced NBA metrics and how to think beyond the boxscore. Today we tackle Offense.

For example:

NBA Stats have come quite a long way actually. Let’s look at a late 70s Sixers boxscore:

Boxscore

As you’ll see, rebounds and assists did not even show up in your typical newspaper boxscore the day after a game. The game essentially boils down to one stat. Our team needs to score more points than the other team. When you view the game in those simple terms, it’s easy to see why points per game attain primacy as the stat by which most players are judged.

Layer 1 – Counting Stats

Allen Iverson

Career  PPG 26.7  RPG 3.7 APG 6.2

This is what we would call “counting stats.”

When you want to compare two players, these three stats are the most common way to start. But when you think about the game of basketball, it’s pretty clear that these three metrics are, at best, incomplete when considering the overall effectiveness of a player. Iverson ranks #7 all time in points per game average. For superstar level players, these stats are fairly easy filters to gauge raw productivity.

But when trying to predict the future, especially when considering a player’s effectiveness in a new role or situation, these raw metrics quickly become inadequate.

Iverson was “The Guy” in Philadelphia from the day he arrived until he was originally traded. He had an unmitigated green light for the Philadelphia 76ers, and the entire roster was constructed around him.

He was not just a star, he was OUR star. He’s amazing right?

Layer 2 – Efficiency

Field Goal % – Shows what percentage of shot attempts did a player make. Allen Iverson made 42.5% of the shots he took in his NBA career. This may surprise some when you look at his herculean scoring output. To compare, in 2001 with the Philadelphia 76ers, Dikembe Mutombo had a 51% field goal percentage.

In order to score those 27 points per game, Allen Iverson attempted just under 22 shots per game. So from a raw efficiency standpoint, you can divide points scored by shots attempted. you come up with 1.22 points per shot (PPS).

So how good is 1.22 PPS? Well it is equal to Ersan Ilyasova this past season and just barely ahead of Robert Covington. Among guards this past season, 1.22 PPS would not rank in the top 50.

Let’s look at another common efficiency stat known as True Shooting Percentage (TS%). Per Basketball-Reference.com, “True shooting percentage is a measure of shooting efficiency that takes into account field goals, 3-point field goals, and free throws.”

It is a fairly similar metric for enhancing FG% to account for 3 pointers being worth more than 2-point attempts and free throws being earned by virtue of drawing fouls.

Below are the highest rated players by True Shooting Percentage in the NBA last season:

TS%NBA

You will see that this list is a combination of all NBA level talent and very marginal role players. This is what makes TS% and efficiency stats important to note but not a silver bullet for determining greatness. As you can probably imagine, making Anthony Tolliver the focal point of the Detroit Pistons likely would not have led to great results, even if this measure might indicate as much.

But if you need a role player who does not need to take many shots to contribute and will make the most of the shot attempts they get, TS% can be a useful measure. This measure usually favors big men who catch and dunk lobs in the pick and roll. That is among the highest efficiency shot in the NBA, but it’s less of a function of the scoring ability of the player himself than the passing and shot creation ability of the point guard in that offensive system.

Seeing a point guard like Steph Curry atop this list is eye popping because he is the one having to create his own shot or is generating his points from 23’9″ and beyond.

Layer 3 – Ball Dominance

The NBA shot clock is 24 seconds. That is how much time a team has to attempt a shot and at least hit the rim. So how that time is used is important. When you look at a team like the Oklahoma City Thunder or Toronto Raptors, they are more isolation heavy than teams like the Golden State Warriors or Philadelphia 76ers. How do we know that? One measure is how much time their best players hold the ball.

The NBA actually tracks time of possession and even dribbles per possession as stats for its players.

TimeofPossession

Stats per https://stats.nba.com

So each time James Harden and John Wall touch the ball on offense, they hold the ball for an average of 6.3 seconds before passing or taking a shot. This list, unlike the TS% list, should be dominated by point guards. When someone is referred to as a “Ball Stopper” or an ISO guy, this is the kind of metric that can objectively measure that.

Again, a team only has 24 seconds in a shot clock, so you have to choose carefully whose hands you want the ball in most. A point guard is the orchestrator of the offense, and there is nothing inherently wrong with time of possession.

But what you can’t typically do is throw any three ball dominant players together and expect a team to win more.

In 1995, the Philadelphia 76ers selected Jerry Stackhouse with the second overall selection in the NBA Draft. A year later they won the lottery and selected Allen Iverson #1. The thinking heading into the 1996/1997 season was that these two would form a super duo and dominate the league. What occurred was a frustrating mashup of two ball dominant players taking turns trying to beat their man off the dribble.

Despite the fact that Stackhouse scored slightly more than Iverson in 1996/97, the team struggled mightily and he was quickly traded away after just one season playing together with Iverson. Stackhouse was traded for Aaron McKie and Theo Ratliff, two non-ball dominant offensive players.

Let’s quickly do a health check on the 2017/18 Philadelphia 76ers

76ersTOP

This table tells you that Ben Simmons is your point guard and JJ Redick and Joel Embiid are your most efficient scorers from a time standpoint.

Summary – Roles matter

So this is just an introduction to a few different ways to look at NBA players. What we’ve looked at is raw production, how efficiently that production was attained, and how much of the offense a player consumes to produce those numbers. There are multiple layers upon which to view players and attempt to predict their fit and role on a new team, and these are just a very few.

Roles matter very much. It is extremely rare to find a player who is high on production and efficiency and low on time of possession. Those players almost certainly help a team not only score points but win games.

And teams need a mix of players. They need high production players who can take over a game and get you a bucket late in a close game. They need players who can get the team in a position to get good shots offensively. And they also need highly efficient role players who can finish plays and clean up misses.

So was Iverson great? Of course he was! He was perfectly suited to build a late 90s team around, and when you needed a hero, he was very often up to the task.