Price Z-Score

The goal of this Pine Script is to visually represent how much price deviates from its rolling average via the Z-score statistic in TradingView's indicators section. This script first uses a user-definable "lookback" period (the default is 20 bars) to calculate a moving average and standard deviation. Then it displays the price as an amount of standard deviation greater than or less than the moving average. A moving Z-score is plotted along with three reference lines (+2, 0, -2) to indicate areas of unusual extremes statistically; also, it colors the chart green for when price is in the lower half of the Z-score range (oversold) and red for when price is in the upper half of the Z-score range (overbought). These can be used by traders to recognize price has moved out of normal ranges and is due to revert to its mean.