In this indicator, the Z-Score distance is the current standard deviation from the intraday VWAP of the price.

If it exceed a certain deviation (for example 2 standard deviations), the indicator highlights an oversold or overbought area from which the price could tend to return to its mean, the VWAP.

The VWAP is the Volume Weighted Average Price, in this indicator it is computed only for intraday trading and it resets at the defined startTime time value.

So the indicator has four inputs:

• “startTime“: the time at which the VWAP is reset and the Z-Score starts to be drawn
• “endTime“: the time at which the Z-Score iterrupts its drawing
• “smoothZscore“: whether to smooth the Z-Score curve or not
• “stdDev“: the Z-Score oversold/overbought level

// VWAP@Time intraday Z-Score
// 17.11.2020
// Daniele Maddaluno
//
// startTime = 80000
// endTime = 153000
// smoothZscore = f
// stdev = 2

once posLev1=+stdev/2
once negLev1=-stdev/2
once posLev2=+stdev
once negLev2=-stdev

if opentime < startTime or opentime > endTime then
	n = 0
	zscoreT = 0

	priced  = 0
	shared  = 0
	summ = 0

	vwap = close
	vwapstd = 0
else
	n = n + 1
	// This if has been added just for plot reasons
	if n <= 1 then
		zscoreT = 0
	else
		zscoreT = 190
	endif

	priced = priced + (totalprice*volume)
	shared = shared + volume

	if shared>0 then
		vwap = priced/shared

		summ = summ + square(totalprice - vwap)
		vwapstd = sqrt(summ / n)
	endif

endif

if smoothZscore then
	zscore = average[3]((close-vwap)/vwapstd)
	else
	zscore = (close-vwap)/vwapstd
endif

if zscore>=posLev2 then
	drawcandle(posLev2, posLev2*1.25, posLev2, posLev2*1.25) coloured(255, 0, 0, 100) bordercolor(0, 0, 0, 0)
endif
if zscore<=negLev2 then
	drawcandle(negLev2, negLev2*1.25, negLev2, negLev2*1.25) coloured(0, 255, 0, 100) bordercolor(0, 0, 0, 0)
endif

// Manage the coloring of vwap mid line
if zscore > zscore[1] then
	dwapR = 0
	dwapG = 128
	dwapB = 192
else
	dwapR = 255
	dwapG = 0
	dwapB = 0
endif

return zscore coloured(dwapR, dwapG, dwapB, zscoreT) style(line, 2) as "Z-score", posLev1 coloured(168, 168, 168) style(line, 2) as "Level +stdev/2", posLev2 coloured(210, 210, 210) style(line, 2) as "Level +stdev", negLev1 coloured(168, 168, 168) style(line, 2) as "Level -stdev/2", negLev2 coloured(210, 210, 210) style(line, 2) as "Level -stdev", 0 coloured(168, 168, 168) style(dottedline) as "Level 0"