diff --git a/conest-senior-review.md b/conest-senior-review.md index e3a8da5..e12097e 100644 --- a/conest-senior-review.md +++ b/conest-senior-review.md @@ -2,7 +2,12 @@ id: aliases: [] title: ConEst Senior Review -tags: [] +tags: + - authorship/original + - destiny/permanent + - occupational + - status/not-started + - type/process dg-publish: true --- # ConEst Senior Review diff --git a/estimator-calibration.md b/estimator-calibration.md index 458c4f4..cbd4390 100644 --- a/estimator-calibration.md +++ b/estimator-calibration.md @@ -188,7 +188,7 @@ As of when? > How many gallons are in a bushel (they are both measures of volume)? I wonder if Hubbard had the same thought I did -while reading [[macgregor_1994_judgemental-decomposition|MacGregor et al. (1994)]]. +while reading [[macgregor_1994_judgmental-decomposition|MacGregor et al. (1994)]]. > How many sovereign rulers has England had in the last thousand years? diff --git a/lucky-fools.md b/lucky-fools.md index c8e7f59..d981ff1 100644 --- a/lucky-fools.md +++ b/lucky-fools.md @@ -16,8 +16,14 @@ especially if they sincerely believe that their success _was_ due to their competence. %% -Books concerned with lucky fools: -[[taleb_2001_fooled-by-randomness]] -[[kahneman_2011_thinking]] -[[hubbard_2020_failure]] +somewhat related: +* [hot hand fallacy](https://en.wikipedia.org/wiki/Hot_hand) +* [gambler's fallacy](https://en.wikipedia.org/wiki/Gambler%27s_fallacy) +%% + +%% +Books concerned with lucky fools: +* [[taleb_2001_fooled-by-randomness]] +* [[kahneman_2011_thinking]] +* [[hubbard_2020_failure]] %% diff --git a/macgregor_1994_judgemental-decomposition.md b/macgregor_1994_judgmental-decomposition.md similarity index 100% rename from macgregor_1994_judgemental-decomposition.md rename to macgregor_1994_judgmental-decomposition.md diff --git a/megan-blizard.md b/megan-blizard.md index 034a79a..9a338c8 100644 --- a/megan-blizard.md +++ b/megan-blizard.md @@ -2,7 +2,12 @@ id: aliases: [] title: Megan Blizard -tags: [] +tags: + - authorship/original + - destiny/permanent + - occupational + - status/not-started + - type/person dg-publish: false --- # Megan Blizard diff --git a/timestamped/2026-01-25_21-02-00.md b/timestamped/2026-01-25_21-02-00.md index 32212ad..99f15e7 100644 --- a/timestamped/2026-01-25_21-02-00.md +++ b/timestamped/2026-01-25_21-02-00.md @@ -18,7 +18,7 @@ In [[hubbard_2020_failure#Break It Down, Then Do the Math]] Hubbard introduces **decomposition** as a method for reducing error in estimates, Providing Fermi's "piano tuners in Chicago" problem as an example, without acknowledging that _Fermi_ supplied the decomposition. -Hubbard also references [[macgregor_1994_judgemental-decomposition]] +Hubbard also references [[macgregor_1994_judgmental-decomposition]] which is a similar case. Neither of these examples suggest that decomposition is a magic bullet, _or even that a layman's decomposition wouldn't be worse than nothing._ diff --git a/timestamped/2026-01-25_22-59-00.md b/timestamped/2026-01-25_22-59-00.md index 60c794e..bf51a21 100644 --- a/timestamped/2026-01-25_22-59-00.md +++ b/timestamped/2026-01-25_22-59-00.md @@ -8,7 +8,9 @@ dg-publish: true --- # 2026-01-25 22:59:?? -[[macgregor_1994_judgemental-decomposition]] +## _Judgmental Decomposition_ + +[[macgregor_1994_judgmental-decomposition]] I really hate this study. diff --git a/timestamped/2026-04-02_19-10-14.md b/timestamped/2026-04-02_19-10-14.md new file mode 100644 index 0000000..79c3bde --- /dev/null +++ b/timestamped/2026-04-02_19-10-14.md @@ -0,0 +1,42 @@ +--- +id: 2026-04-02T19:10:14-04:00 +aliases: [] +title: 2026-04-02 19:10:14 +tags: + - authorship/original + - destiny/permanent + - status/draft + - type/periodic/timestamped +dg-publish: true +date-created: 2026-04-02T19:10:14-04:00 +daily: "[[2026-04-02]]" +weekly: "[[2026-W14]]" +monthly: "[[2026-04]]" +quarterly: "[[2026-Q2]]" +yearly: "[[2026]]" +--- +# 2026-04-02 19:10:14 + +From a high-level, business proposition perspective +[[construction-estimating]] is identical in function to stock trading, +both typified by expert judgement under uncertainty +... +One significant difference despite their similarity +is that only in stock trading is it well understood +that individual loss is not only inevitable, +_it is how the strategy works._ +If you're not losing sometimes +you're not assuming enough risk +and you're missing out on returns. + +Similar sentiments expressed in the context of construction contracting +are not popular, and are frequently judged irresponsible. + +I believe the tendency to set standards for estimates +beyond the optimal level of detail +stems from a [cognitive bias of association](https://en.wikipedia.org/wiki/List_of_cognitive_biases#Association) +or [relevance fallacy](https://en.wikipedia.org/wiki/List_of_fallacies#Relevance_fallacies) +which leads otherwise rational estimators +to the erroneous belief that because construction is physically tangible, +risk control is more effective than in markets. +This may be related to [[2026-04-02_20-41-59#Decomposition Fallacy]]. diff --git a/timestamped/2026-04-02_20-41-59.md b/timestamped/2026-04-02_20-41-59.md new file mode 100644 index 0000000..2cc674d --- /dev/null +++ b/timestamped/2026-04-02_20-41-59.md @@ -0,0 +1,61 @@ +--- +id: 2026-04-02T20:41:59-04:00 +aliases: [] +title: 2026-04-02 20:41:59 +tags: + - authorship/original + - destiny/permanent + - status/draft + - type/periodic/timestamped +dg-publish: true +date-created: 2026-04-02T20:41:59-04:00 +daily: "[[2026-04-02]]" +weekly: "[[2026-W14]]" +monthly: "[[2026-04]]" +quarterly: "[[2026-Q2]]" +yearly: "[[2026]]" +--- +# 2026-04-02 20:41:59 + +## Decomposition Fallacy + +I have expressed in other notes[^1] my frustration +with how estimate decomposition is most frequently explained: +as an intuitive process which can not be performed incorrectly +and by definition creates a more accurate estimate. + +[^1]: * [[2026-01-25_21-02-00]] + * [[2026-01-25_22-59-00]] + +The argument that an estimate based on the aggregation of intermediate estimates +is necessarily more reliable than one made in one go +is intuitive, but a [non sequitur](https://en.wikipedia.org/wiki/Formal_fallacy). + +Frequently, decomposition is explicitly _unhelpful_ +due to its neglect of the [portfolio effect](https://financial-dictionary.thefreedictionary.com/portfolio+effect). +If an estimator can give a high confidence estimate +of total dollars spent on rental equipment over the life of a project, +it does not follow that they could give one for +dollars spent on scissor lifts alone with greater or even equal confidence.[^2] + +[^2]: I chose this example specifically + because it has been an issue at both EC's I've estimated for. + We set a target based on some well founded model + (\$0.25 per direct labor hour or 1% of total sell price), + then 3--4 decently paid estimators spend up to an hour + discussing how to make that target + from quantities and durations of individual pieces of equipment. + Ultimately none are totally satisfied with it, nor should they be, + since the actual quantities, durations, and equipment types will be quite different, + and the entire exercise was pointless. + +My criticism is not entirely fair, however. +Fermi and MacGregor's estimation problems have correct answers +and are thus a different class entirely +from those I'm most familiar with. +I choose to criticize decomposition generally despite this +because the distinction is rarely acknowledged by its advocates +so "decomposition = good" pervades the estimating zeitgeist completely +and I get baffled, horrified, or patronizing looks when I suggest +that complete quantity takeoff may not be more accurate +than a parametric budget that could be completed in a day.