52 lines
1.7 KiB
Markdown
52 lines
1.7 KiB
Markdown
# Estimating Detail
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In [[construction-estimating]], the acceptable level of detail of an estimate is a contentious subject.
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What's worse, estimators often disagree on what makes an estimate more detailed than another.
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With our [[risk-oriented-estimating]] approach,
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detail is essentially the inverse of epistemic [[uncertainty]].
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That said, the correct answer is this.
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> As detailed as possible, given required turnaround and available estimating resources.
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%%
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TODO: This analysis is not much better than the common belief.
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A commonality of both is the implication that more time ought to be preferred,
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when the reality is that when considering larger organizational factors (strategy),
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ideal estimate certainty is likely far lower than most expect.
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The *correct* correct answer involves optimizing for these factors:
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* value of increased bid certainty
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* value of increased estimate volume
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%%
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An estimate's detail is irrelevant to its quality.
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A less detailed estimate is a more [[risk]]y bid,
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but **it is not the role of the estimator to determine acceptable risk**.
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## Experiment
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Perform a system takeoff (lighting for example) in exacting detail,
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the maximum amount you would ever consider using,
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and measure the time required to do so,
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as well as the cost of the scope.
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Have another estimator takeoff the same scope using the proposed time saving strategy.
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Repeat the test on additional projects.
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Treat the detailed takeoff as the true value
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and find the error of the time saving strategy.
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$\frac{d\sigma}{dt}$
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### Expectation
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Time-saving strategies will overestimate or underestimate detailed takeoff
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depending on the assumptions used in their creation.
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## Human Error
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It is commonly understood that a "detailed takeoff"
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is more "accurate" than a square foot estimate.
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