The basic calculation of Player won-lost records is described here. A somewhat lengthy (53-page PDF) discussion of comparing players using Player won-lost records, focusing on positional averages is here. Recent changes to Player won-lost records which were made in July and August of 2019 are described here. Player won-lost records are compared to WAR (as calculated by Baseball-Reference and Fangraphs) in an article here.
For a more in-depth description of Player won-lost records, how they are calculated, and who the best players of the past 80 years were in various aspects of Player won-lost records, I have published a book with McFarland, entitled Player Won-Lost Records in Baseball: Measuring Performance in Context.
I have self-published two additional books, which are available as free PDF downloads on my website, or for purchase in either paperback or Kindle format at Amazon. See here for more details.
I gave a presentation to the Chicago chapter of SABR (Society for American Baseball Research) on November 18, 2017. I have posted video of the presentation and follow-up Q-and-A on YouTube. The video runs almost exactly one hour. I also have a couple of shorter (5-10 minute) videos up on YouTube as well: see here.
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