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+---
+tags:
+  - topic/estimating
+  - destiny/uncertain
+  - type/philosophy
+title: Traditional Estimating Methods
+---
+# Traditional Estimating Methods
+
+Also "single-point estimation"
+as opposed to the standard three-point.
+
+"Traditional estimating methods"
+as referenced frequently in [[this-notebook]]
+are those [[construction-estimating]] methods that produce:
+
+* an _exhaustive_ and _specific_ bill of material
+* a single, definitive final price for each bid item
+
+Such methods lack the ability to intelligently express [[uncertainty]].
+
+### Limitations of Traditional Estimating Methods
+
+Traditional estimating methods,
+sometimes referred to as "Detailed Takeoff",
+seek to detail all constituent subcosts,
+including 100% itemized pricing by way of a _material extension_,
+a complete list of all material included in the price.
+
+For clarity and contrast to [[risk-oriented-estimating]],
+which does not require itemized pricing,
+I'll refer to these methods as "item-oriented estimating".
+
+By popular belief,
+item-oriented estimating is the only "correct" way to estimate,
+however few to no estimators create 100% "detailed" estimates
+as the effort would require a significant increase in estimating time
+for little reward in overall **precision**.
+
+> [!info] Pareto Principle
+> The Pareto principle states that for many outcomes,
+> roughly 80% of consequences come from 20% of causes.
+>
+> In the case of estimating efficiency, this means that optimal strategy
+> is to focus on the 20% of estimating effort
+> representing 80% of the overall efforts contribution to the total.
+
+It is popular to dismiss alternate estimate models as potentially inaccurate,
+but this dismissal fails to acknowledge
+the potential for _much greater_ inaccuracy in item-oriented methods:
+
+While an estimate based on item extension is 100% **precise**,
+in that it computes to single final number,
+the method has no such inherent guarantee of **accuracy**.
+It relies on the estimator to miss absolutely nothing,
+and to adjust for all labor conditions and market factors _exactly_.
+
+Most estimators wouldn't rate their margin of error at less than 10%,
+though most would refuse to answer anyway (see [[estimating-culture]]).
+
+#### Required Hyper-Specificity
+
+%% TODO:
+This section is a transcription of a dictation.
+To be condensed.
+%%
+
+The reason that it's such a big deal to change between 1-hole straps and and unistrut straps
+is because it takes so long to do.
+If it was as simple as it is to visualize,
+which it could be if you were drawing these things and it was being interpreted,
+rather than having to explicitly specify every aspect of what you wanted.
+Then that would make a huge difference.
+
+In the (granted, limited) market segment that we've worked in,
+I use ~10 assemblies on a regular basis.
+That makes up 99% of the work.
+Why are there hundreds in in our database?
+They just need to be better.
+You could probably get away with hard coding some of this,
+even if that irks me,
+if they were good.
+It's just that it doesn't seem to be a goal
+that Trimble or anybody else has.
+
+#### Assumed Finality
+
+While they may support a multitude of creative methods to create takeoffs,
+traditional methods are rarely as convenient when it comes to modify those takeoffs,
+as is frequently necessary as in the case of mistakes and revisions.