This page explains how Qi Guo (USATT# 80876)'s rating went from 1888 to 1884 at the Topspin Open League event from 8 May 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.