True Strength Index (TSI)

The true strength index, from William Blau, smooths price momentum twice, then divides by the same double smoothing of the absolute momentum. The division bounds the result roughly between -100 and +100. Double smoothing cuts the noise that a raw momentum line has, at the cost of more lag. Zero is the centre.

A rising TSI says the smoothed up-momentum is gaining on the smoothed total movement. Crosses of a signal line are the usual trigger. Divergences between price and TSI are used the same way as RSI divergences, and they fail the same way if you skip the price confirmation. Because of the long default window, TSI is a swing tool, not a scalp tool.

A cross up through the signal line while TSI is below zero is the classic long trigger in this method. In an uptrend, holding above zero is the regime, and dips of TSI toward zero are the pullbacks.

A cross down through the signal while above zero is the classic short trigger. Holding below zero is the bearish regime. A strong trend will keep TSI on one side of zero and make countertrend crosses fail.

Shortening 25 and 13 until TSI looks like RSI, then being surprised that it whipsaws. The long smoothing is the point. Also treating the signal cross as a price target.

Double EMA lag means TSI turns after a V-reversal is already obvious on price. Use it to stay with a swing that has begun, not to catch the spike low.