This page explains how Jon Dorn (USATT# 37971)'s rating went from 1948 to 1920 at the 2012 Austin Fall Classic Round Robin held on - 13 Oct 2012. The links below take you to pages that describe various aspects of the rating processor.

The rating processor goes through 4 passes in order. The links take you to pages that provide detailed explanations of the calculations during each of the 4 passes.