The major effort occurs early in the inception phase; thereafter, the system should be assessed at the beginning of
each iteration to ensure that the design is still on track with the architecture (see Capability Pattern: Assess and Plan Iteration).
Estimation should ideally be based in the organization's own experience, which is then used to calibrate an estimation
model, such as COCOMO. (See http://sunset.usc.edu/research/cocomosuite/index.html.) If no
other data are available and you are using default values for model coefficients, it will be important to use
other methods to validate the estimates. It is just as important to obtain staff and other stakeholder agreement
that the estimates are realistic and achievable. However, take into account the experience of staff giving feedback
about estimates. More junior staff may be just guessing numbers and then adding large margins for error; conversely,
their effort estimates may be naively low. Be circumspect when dealing with estimates from junior staff, and be
prepared to counsel them when necessary, and offer the assistance of a more experienced peer.
All enclosed plans and sections of the Software Development Plan should be evaluated through internal walkthroughs and
reviews.
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