Regularized Adjusted Plus-Minus (RAPM) is the standard framework for estimating individual player impact in basketball. Its application requires possession-level stint data -- records of which five players shared the court for each contiguous sequence of possessions -- a form of data the NBA did not systematically record until the late 1990s. This paper describes the construction, methodology, and validation of the first possession-level player impact database for the pre-play-by-play NBA era, covering the regular seasons from 1984--85 through 1995--96, spanning twelve published seasons. As of this writing, 2,179 regular-season games have been reconstructed across twelve published seasons, comprising 435,760 total logged possessions and 1,012 distinct player-seasons. Every game was manually reconstructed from broadcast video: lineup changes were logged at every dead-ball substitution, possessions were tallied directly from footage, and points scored by each lineup were recorded. RAPM is estimated via weighted ridge regression applied to the reconstructed stint data, using the identical mathematical framework applied to modern play-by-play records. We provide a rigorous treatment of the reconstruction protocol, the formal properties of the estimation procedure, uncertainty quantification through posterior credible intervals, a multi-criterion validation framework, and an analysis of sampling properties at partial coverage. The resulting database is the only possession-level individual impact record for this era and provides a foundation for historical analysis that has until now been technically inaccessible.

翻译：正则化调整正负值（RAPM）是评估篮球运动员个人影响力的标准框架。其应用需要获取回合级轮换数据——即记录每个连续进攻回合中同场竞技的五名球员组合——这类数据直到20世纪90年代末才被NBA系统记录。本文描述了首个NBA早期（涵盖1984-85至1995-96赛季共12个常规赛季）回合级球员影响力数据库的构建方法、技术流程与验证过程。截至目前，已重建12个赛季的2,179场常规赛，累计记录435,760个回合与1,012个球员赛季数据。每场比赛均通过转播视频人工重建：在每次死球换人时记录阵容变动，直接统计比赛录像中的回合数，并记录各阵容的得分情况。采用加权岭回归对重建的轮换数据进行RAPM估计，数学框架与应用于现代逐回合记录的方法完全一致。我们提供了重建方案的严格论证、估计过程的数学性质分析、基于后验可信区间的不确定性量化、多准则验证框架，以及部分覆盖条件下的抽样特性分析。该数据库是目前唯一涵盖该时期的回合级球员影响力记录，为此前技术上不可及的历史分析提供了基础。