The indicator is very similar to the WMA (viewtopic.php?f=38&t=59621).
Formulas for WMA:
WMA[i] = (Price[i] - WMA[i-1])*k + WMA[i-1], where
k = 1/Length.
Formulas for Mod. WMA:
ModWMA[i] = (MVA(i) - ModWMA[i-1])*k + ModWMA[i-1], where
k = 1/Length.
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