In order to more accurately apportion credit for defensive credit among the players on a team, it is necessary evaluate the performance of the players he guards within the context of that opponent’s typical performance. My Matchup-Based Defense model does precisely this, by comparing a player’s effectiveness with the defensive load he is forced to carry.
The basics of the method are here and here. For an overview of defensive matchup data for the entire league along with a visualization-packed walkthrough, please consult my Tableau Story. Under the “Matchup-Based-Defense” category on the blog, you can find an analysis of the top defenders in the league for the 2019-20 season, as well as a series of posts breaking down the best defenders at each position during the 2018-19 season. In addition, you can pull up a “player card” of defensive performance for any player since matchup data became available using the Google Sheets tool. I have also used the model in conjunction with my Points Created offensive model to create the Advanced Box Score – a new era game log that includes every aspect of the game rather than only the events recorded in the traditional box score.