Measuring Spatial Allocative Efficiency in Basketball
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Every shot in basketball has an opportunity cost; one player's shot eliminates all potential opportunities from their teammates for that play. For this reason, player shot efficiency should ultimately be considered relative to lineup. This aspect of efficiency—the optimal way to allocate shots within a lineup—is the focus of our paper. Allocative efficiency is fundamentally a spatial problem because the distribution of shot attempts within a lineup is highly dependent on court location. We propose a new metric for spatial allocative efficiency by comparing a player's field goal percentage (FG his field goal attempt (FGA) rate in context of both his four teammates on the court and the spatial distribution of his shots. Leveraging publicly available data provided by the National Basketball Association (NBA), we estimate player FG model. Then, by ordering a lineup's estimated FG with the lineup's empirical FGA rate rankings, we detect areas where the lineup exhibits inefficient shot allocation. We estimate and visualize this inefficiency, and identify which players are responsible. Lastly, we analyze the impact that sub-optimal shot allocation has on a team's overall offensive potential, demonstrating that inefficient shot allocation correlates with reduced scoring.
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