Individual Player Value (“IPV”) is a stabilized in-season RAPM model which uses a robust machine learning based SPM metric (“FORPM”) as a prior for RAPM. There is no previous season information used, to put it on par with other in-season metrics such as NPI RAPM, PER, WS, or EZPM. The choice of a FORPM metric as prior (using an ensemble consisting of random forest regressions and gradient boosting), rather than a traditional SPM metric, was made in part to eliminate discretion in variable selection, with the goal of making IPV a pure metric. In addition, a properly specified FORPM model (fit to SRS) performs much better out of sample than more plain vanilla regression-based models (especially with regard to ‘defense’). Due to not using any previous year info or an aging/experience curve, these values should be considered as descriptive more so than as predictive. The model is based on ‘basketball’, and not on ‘offense’ nor on ‘defense’, and as such there is only one coefficient for each player. This is again both for purity of the metric, and due to this approach being more predictive out of sample. Individual Player Values here are not meant to imply player rankings, nor are they meant to imply that they are the players value if he were to be traded, or have his role changed on his team.
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A lot of people have been asking us on Basketball Twitter and APBR for a full list of RAPM values for the NBA, so we decided to oblige with the version that most people requested. The below numbers are created as follows: