True Strength Index
a.k.a. TSI
A momentum oscillator built from double-smoothed price changes, swinging above and below zero.
In plain English
A momentum oscillator built from double-smoothed price changes, swinging above and below zero.
The True Strength Index (TSI), developed by William Blau, takes the bar-to-bar change in price, smooths it twice with exponential averages, and divides it by the double-smoothed size of those changes. The result swings between roughly -100 and +100.
Above zero, momentum favours buyers; below, sellers. Traders use crossovers with a signal line, zero-line crosses and extreme readings. Like any oscillator, it is better as confirmation than as a standalone trigger.
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