Technical Background for "A Precision Medicine Approach to Develop and Internally Validate Optimal Exercise and Weight Loss Treatments for Overweight and Obese Adults with Knee Osteoarthritis". - Xiaotong Jiang; Amanda E. Nelson; Rebecca J. Cleveland; Daniel P. Beavers; Todd A. Schwartz; Liubov Arbeeva; Carolina Alvarez; Leigh F. Callahan; Stephen Messier; Richard Loeser; Michael R. Kosorok (CoRR, 2020)