Overlay · stderrbands
What it computes
A Smooth-bar SMA of the end value of a least-squares line over the last Length closes, with bands StdErr times a Smooth-bar SMA of that line’s standard error above and below it.
It describes bars that have already printed. QuantZ does not claim this indicator has predictive value, and it is not a recommendation to do anything.
Inputs and lookback
- Length · default 21
- StdErr · default 2
- Smooth · default 3
Reads open, high, low and close from the loaded bars. It produces nothing until at least 23 bars are loaded, a settling period no parameter shows.
What it assumes about the series
- Bars arrive oldest to newest at one interval, each with a finite open, high, low and close. The input is the chart’s loaded series, whatever its length.
- The function is given bars, not sessions: it does not know the timeframe, where a session opens, or that a gap in the tape is a gap.
- Warm-up bars are omitted rather than padded. The first value appears once the arithmetic has enough history, and nothing is drawn before it.
- The newest bar is the forming bar. Its value uses the live close and settles when the bar closes.
- The standard error is that of the estimate: squared residuals divided by Length − 2. The Regression Channel divides by Length, so at the same settings its bands are narrower.
Whether a drawn value can change
forming-bar · Moves only on the forming bar. The newest bar’s value moves with its live close until that bar closes. A closed bar’s value is final and is not redrawn when later bars arrive.
This class is read from the registry entry and checked by a test against the function itself: for a class that says closed bars are final, appending a bar must leave every earlier point unchanged, and for a class that says they are not, it must not.
Outside its inputs
- Nothing outside the loaded bars: no longer history than the chart has loaded, and no other interval.
- Nothing inside a bar: no individual trades, no order book, no bid or ask.
- No other symbol, no benchmark, no news, no fundamentals, no earnings dates.
- Volume is not read at all.