These analysis options are highly influenced by timing of the
analysis. The forward pricing (commonly termed as Prospective
Analysis) is usually carried out when the project is in progress
and the contractor and/or the employer representative (engineer/
architect) needs to forecast the impact of known events on the future
completion date for purposes of estimating an extension of
time, for example. This analysis is thus often branded theoretical
(Pickavance 2005), in the sense that it does not consider the actual
delays that occurred, but seeks to demonstrate what might have
been the delay arising from particular events. On the other hand,
the Hindsight analysis (commonly termed Retrospective Analysis)
is performed after the project is completed (i.e., after the fact), when
analysts would have the full benefit of hindsight. Such analysis
is considered to be actual and therefore more reliable as it focuses
on identifying the actual delays experienced, their time of
occurrence, and the events or circumstances that gave rise to them
(Pickavance 2005).
The mode of application of the techniques methodologies varies
based on three different modes of operations: direct analysis,
subtractive simulation, and additive simulation.