For software then I tend to use ...
Likely effort = estimated effort * ((total time allocated / single largest block of time)^1/3)
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Replying to
e.g.
estimated effort = 10 days
time allocated = 50 days (1 day /wk)
single largest block = 5 days
likely effort = 10* (50/5)^1/3 = 21 days
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Replying to
or
estimated effort = 10 days
time allocated = 50 days (1 day /wk)
single largest block = 2 days
likely effort = 10* (50/2)^1/3 = 29 days
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