moving average of the difference between the 'close' and 'ohlc4',
which is compared to a 20-days with a standard deviation of one.
This menas that when the 3-day curve is above the upper limit, the Uncetainty is
higher than it has been during 84% of the last 20 day period (and vice versa for
the lower limit).
By using Open,High,Low,Close you get four opinions of what the price should be for
the current period. If there is a difference between 'close' and 'ohlc4' there seem
to exist an uncertainty if the closing price is correct.
Can we say anything about direction? I don't think so; either the 'close king' has
to listen to its 'people' and move toward 'ohlc4', or the other way around.
A way to see if the uncertainty increases over time could be to see if:
abs(close - ohlc4) < abs(close - ohlc4) ,which say that we are more uncertain
this period than the in previous one.
And I guess, with increased uncertainty comes 'fear' of loosing money.