Let’s break it down in simple terms even the casual fan can understand. In its simplest form, plus-minus is exactly what it sounds like – when a given player is on the floor, be it for a single game, group of games or a season, does his team get outscored or does it outscore the opponent?
This very simple metric is housed in most common single-game box scores, and is the rawest way of determining what sort of effect a player has on his team (and the opponent) while on the court.
His versatility defensively is a huge plus – Middleton’s capability to guard up to four positions in the right situations made him a plug-and-play piece who could fit with plenty of different lineup combinations.
In the long run, these elements plus Middleton’s ability to stay within his role on both ends of the floor made him a Plus-Minus All-Star, and there’s no question the rise in prevalence of these measures at the front office level contributed to him receiving a hefty pay day last offseason.
The statistician can control for such elements as coaching, opponent, time in between games and more.
They can also use longer stretches of prior games to “inform” the model (the process of setting a concrete statistical baseline with which to compare subsequent players).
In general, while we do see examples of big positive outliers offensively, the majority of them tend to come on the defensive end where aggregating counting stats has always been more difficult.
On the other side of the coin, traditional stats have inflated certain players’ reputations to a point that APM metrics disagree with, sometimes strongly.The results of such a simple statistic can often have tons of noise involved, however, and those in the statistical community have derived more advanced measures to help add detail and context.This process, and the resulting outputs, are most commonly referred to as Adjusted Plus-Minus (APM).Let’s look at a simple example of how this sort of thing can be useful even for the casual observer: Quantifying a player’s defensive abilities has always been one of the toughest areas within analytics.Anyone with a keen eye and experience can get a good rough idea by watching players, and one can use NBA.com’s advanced on/off court logs to determine that a team tends to suffer defensively when one particular player steps on or off the court.There are a few other tracking services (such as Synergy Sports and Sport VU cameras) that can assist us here.