This table provides an unprecedented breakdown of a player's impact on the game. It's a revolutionary way to understand player value, dissecting their RAPM (Regularized Adjusted Plus-Minus) into specific categories of impact. These were derived using regularized adjusted factor data. Zero box score stats were used, so you may see weird values for shorter duration and lower minute guys.
The table shows how many points per 100 possessions a player contributes in each of these key areas:
These six factors sum up to closely match the player's overall RAPM, providing a detailed view of where a player's value truly lies. This breakdown offers insights that traditional stats or even overall RAPM can't provide.
The 'oposs' (Offensive Possession Impact) and 'dposs' (Defensive Possession Impact) columns combine the turnover and rebounding impacts for offense and defense respectively. The 'poss val' column represents the total possession impact. The top RAPM guys of all time also drive value in the possession game. Nobody ever talks about how low Michael Jordan's turnover rate was, but I assure you it drove significant offensive value.
Additionally, the table includes ORAPM (Offensive RAPM), DRAPM (Defensive RAPM), and overall RAPM columns for a complete picture of a player's impact.
This table is invaluable because it reveals the relative importance of different aspects of the game, which isn't always intuitive. It allows us to see not just that a player is valuable, but exactly how and where they provide that value.
For a deeper understanding, pay special attention to players like Stephen Curry, Chris Paul, and Steven Adams. Analyzing their breakdowns can lead to some enlightening "aha" moments about how different players impact the game in unique ways.
NBA advanced impact metrics are designed to quantify a player's overall contribution to their team's success. These metrics go beyond traditional box score statistics to capture the nuanced ways a player influences the game, attempting to measure aspects of performance that may not be immediately apparent.
Impact metrics aim to answer questions such as: How many more points does a team score (or prevent) with a particular player on the court? How does a player's presence affect the overall efficiency of their team's offense or defense? These metrics are particularly valuable for identifying players who contribute significantly to winning in ways that might not be reflected in traditional statistics.
RAPM is a foundational impact metric in basketball analytics that estimates a player's contribution in points per 100 possessions. It considers both offensive and defensive impact and is designed to be relatively unbiased regarding playstyle.
RAPM is particularly noteworthy for its ability to capture the value of players who contribute to winning in ways that aren't always reflected in traditional statistics or even other advanced metrics. It does this by focusing solely on how a player impacts the scoreboard, regardless of their individual stat accumulation. RAPM ignores the boxscore.
RAPM uses ridge regression, a statistical technique that helps address the "multicollinearity" problem arising from players frequently playing together. It analyzes how the score changes when players enter or leave the game, while accounting for the quality of teammates and opponents.
Time Decay RAPM: This variation applies an exponential decay function to a player's entire history, giving more weight to recent performance. It's particularly useful for capturing a player's current level while still considering historical data.
3 Year Recency RAPM: This approach uses the last 3 years of data, with heavier weight on more recent possessions. It balances capturing established performance levels with current trajectory.
Lifetime RAPM: A comprehensive 28-year calculation incorporating an age curve to account for typical player development and decline. It's valuable for historical player comparisons and understanding career arcs.
EPM is an advanced impact metric that combines box score data with play-by-play data to estimate a player's impact per 100 possessions. It aims to provide a more stable and predictive metric than pure RAPM while still capturing the depth of a player's impact.
EPM was developed to address some of the limitations of pure RAPM while maintaining its strengths. It incorporates individual player actions to provide a more granular view of player impact.
EPM uses a two-step process:
For more detailed information and current EPM rankings, visit Dunks and Threes.
DARKO is an advanced player projection system that uses machine learning techniques to estimate player impact. Unlike many other metrics, DARKO updates its projections daily, providing a real-time view of player performance and potential.
DARKO uses a Kalman filter, a statistical technique often used in time series analysis and control systems. This allows the model to update its estimates of player skill in real-time as new information becomes available.
DARKO is particularly useful for player evaluation, team construction, identifying undervalued players, and projecting player development. Its daily updates make it valuable for applications like daily fantasy sports.
For up-to-date DARKO projections and more detailed explanations of the methodology, visit DARKO.app.
LEBRON is a comprehensive impact metric that aims to capture a player's total contribution to winning. It combines box score data with on/off impact data and incorporates various adjustments to provide a nuanced view of player value.
LEBRON uses a multi-step process:
LEBRON values are expressed in points per 100 possessions above average, with 0 representing an average player. The metric also includes Wins Added calculations to estimate a player's total impact over a season.
For a more detailed explanation of LEBRON methodology and current player ratings, visit the BBall Index LEBRON Introduction.
DFG metrics are advanced defensive statistics that measure a player's impact on opponent shooting and rim protection. These metrics provide insights into a player's defensive effectiveness beyond traditional box score stats.
For most of these metrics, negative values are better as they indicate that the player's presence reduces opponent shooting efficiency or frequency of attempts at the rim. The contest metrics (per 100) are exceptions, where higher values indicate more active defensive engagement.
Passing metrics provide insights into a player's playmaking abilities and efficiency in distributing the ball.
Higher values are generally better for most metrics, except BadPass% where lower values indicate better ball security. These metrics together provide a comprehensive view of a player's passing ability, frequency, and efficiency.
Defensive playmaking metrics measure a player's ability to disrupt the opponent's offense and create turnovers.
Higher values are generally better for all these metrics. STOP% is a comprehensive metric that captures overall defensive playmaking ability. It represents the percentage of possessions where the player directly causes a change of possession through steals, drawn offensive fouls, or recovered blocks.
The Four Factors are key components that contribute to a team's success. They are:
These factors are calculated using on/off court data. By comparing how these factors change when a player is on the court versus off, we can estimate their career impact in each area on both ends of the court.
Importantly, a player's Four Factors can predict their non-age adjusted RAPM with a 0.95 r^2. This means the Four Factors are extremely valuable in explaining why a player may have a high or low RAPM.
Read these statistics as percentage increases or decreases to the team's four factors Effective Field Goal %, Turnover %, Offensive Rebound %, Free Throw rate These RA-four factors reveal the drivers behind a player's RAPM Positive numbers indicate positive impact in that area.
2 Year RAPM. Includes playoffs and rubberband adj.
Credit: Jeremias Engelmann.
I've carefully chosen these stats to provide insight into a player's passing impact. Here's what they mean:
28-Year Lifetime RAPM is a stat that measures how much a player impacts winning over their entire career, relative to their age, using data from 1997 to 2024.
The Four Factors are key components that contribute to a team's success. They are:
These factors are calculated using on/off court data. By comparing how these factors change when a player is on the court versus off, we can estimate their career impact in each area on both ends of the court.
Importantly, a player's Four Factors can predict their non-age adjusted RAPM with a 0.95 r^2. This means the Four Factors are extremely valuable in explaining why a player may have a high or low RAPM.
By considering both the overall RAPM and the Four Factors, you can get a more complete picture of how a player contributes to their team's success over their career, taking into account their performance relative to their age and specific areas of impact.
This section explores the intriguing relationship between two metrics that measure a player's impact on opponent turnovers:
A measure of a player's ability to disrupt opposing offenses, representing the number of turnovers they force per 100 possessions above or below the league average. This metric is derived from box score statistics, specifically combining steals and offensive fouls drawn.
The impact on opponent turnover rate derived from RAPM (Regularized Adjusted Plus-Minus) analysis of lineup data, independent of box score statistics.
By comparing these metrics, we gain insight into the value of lineup-based analysis versus traditional box score statistics. This comparison reveals potential hidden contributions to forcing turnovers that may not be captured by steals and drawn fouls alone. It's worth noting that while RA-DTOV may capture indirect ways of forcing turnovers, it is also subject to the inherent variability in RAPM and lineup analysis. Nevertheless, it shows how well lineup-based analyses can largely agree with what the boxscore based analysis would suggest.
The significance of this analysis is underscored by the substantial impact of turnovers on game outcomes. In terms of plus-minus value, forcing an additional turnover per 100 possessions is roughly equivalent to +1 points per 100 in value, representing a crucial aspect of a player's defensive impact that should not be overlooked.
Note: For players with over 10,000 defensive possessions, rFTOV predicts RA-DTOV with an R² of 0.70, demonstrating a strong correlation between box score-derived and lineup-based turnover impact metrics. This predictive power increases with larger sample sizes, reaching an R² of 0.77 for players with over 40,000 defensive possessions, despite potential underestimation due to mismatched time periods in the datasets.