 InvestHub.com's Finance Dictionary and Glossary of Investment Terms Average True Range  ATR Definition 1.
A measure of volatility introduced by Welles Wilder in his book: New Concepts in Technical Trading Systems.The True Range indicator is the greatest of the following: current high less the current low. the absolute value of the current high less the previous close. the absolute value of the current low less the previous close. The Average True Range is a moving average (generally 14days) of the True Ranges. 

