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THE LAWS OF SOFTWARE PROCESS
projects with few “new” variables (Zeppelin projects), it is low. This gener-
ates a range of unknowns that cannot, by definition, be explicitly measured
at the beginning of the project. Typically, both the number of unknowns
and the likely range of unknowns will diminish as time goes by and the
project acquires the necessary system knowledge (this assumes that the
other factors do not come into play, of course). The result of this is a range
of delivery dates, each with an associated likely range of delivered defects
(unknowns still to be resolved).
Knowledge Variability with Time
This is becoming more and more common in ...