Market analyst and author Tom DeMark has developed many price pattern setups and technical studies, including several oscillators designed to reduce the negative attributes found in the more popular of these tools (see "The trouble with oscillators," Active Trader, August 2006 and "Avoiding oscillator traps," Active Trader, September 2006).

One such oscillator is the TD Range Expansion Index (TD REI), which DeMark detailed in his books, The New Science of Technical Analysis (John Wiley & Sons, 1994), New Market Timing Techniques: Innovative Studies in Market Rhythm & Price Exhaustion (John Wiley & Sons, 1997), and DeMark on Day Trading Options (McGraw-Hill, 1999).