56 lines
1.7 KiB
Markdown
56 lines
1.7 KiB
Markdown
---
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id:
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aliases: []
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tags:
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- topic/estimating
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- type/philosophy
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title: Estimating Detail
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---
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# Estimating Detail
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The acceptable level of detail of an [[construction-estimating|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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The commonly repeated answer is this:
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> As detailed as possible, given required turnaround and available estimating resources.
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This analysis is flawed
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because it implies 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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An estimate's detail is irrelevant to its quality.
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A less detailed estimate is a more [[risk|risky]] 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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