Forecast bias

Forecast bias or the tendency of our model to consistently over- or underestimate
the realizations is a concern of distributions addressed by the separation of upper
and lower quantiles. For a forecast which consistently overestimates the realizations
to a greater extent than to underestimate them, then:
DHkD[DLkD for all k
and similarly, for a forecast which consistently underestimates the realizations to a
greater extent than to underestimate them, then:
DLkD[D HkD for all k
Visually, the forecast DCL value would have the appearance of lying more closely to
one edge of the cumLk/cumHk envelope. This would probably be a good indicator
that the model parameters need some form of adjustment depending on the extent
of bias present in order to rebalance future forecasts.