vault backup: 2025-11-04 16:43:34
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id: the-failure-of-risk-management
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aliases: []
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tags:
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- authorship/original
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- destiny/permanent
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- status/complete
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- topic/risk
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- type/media-commentary
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- authorship/original
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title: _The Failure of Risk Management_
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---
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# _The Failure of Risk Management_
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@@ -45,30 +45,33 @@ Qualitative risk analysis
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(i.e. risk matrices, scoring charts)
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departs from legitimate statistical methodology
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and has no robust evidence to suggest its efficacy.
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There is good reason to believe that such methods
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are deleterious to their intended purpose
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in contradiction to the common response
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In fact, there is good reason to believe that such methods
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are _deleterious_ to their intended purpose,
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in contradiction to the common refrain
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that they are "better than nothing".
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### Utility as a Measure of Value
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Expected Value (Probability × Magnitude)
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alone can not predict or inform risky decisions,
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alone cannot predict or inform risky decisions,
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except for risk-neutral parties,
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but people and organizations are risk-averse.
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and people and organizations are risk-averse.
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Game 1: Which would you pick?
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* Option 1: a 100% chance to receive $10,000
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* Option 2: a 10% chance to receive $100,000
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Most people, being risk-averse, will pick option 1.
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Suppose the prize of option 1 were lowered
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Suppose the payout of option 1 were lowered
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until you would pick option 2.
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That value is your **Certain Monetary Equivalent (CME)**
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for a 10% chance of $100,000.
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For risk-neutral parties, expected value = CME
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For risk-neutral parties, expected value would equal CME
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***
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Another factor at play here
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is that utility is not proportional to monetary value.
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@@ -103,10 +106,22 @@ where $Pr$ is the probability of Payoff.
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### Expert Opinion Must Be ~~Adjusted~~
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Expert opinion is valuable despite its flaws.
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Expert opinion is valuable, but its weaknesses must be compensated for.
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<!-- TODO: -->
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Experts tend to be good at creating heuristics,
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but do not apply them consistently in practice.
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> [!example]
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> Chapter 7 describes a study where individual experts
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> were shown to estimate risk differently for identical cases.
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> [!example] p. 198
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> Models based on expert opinion consistently outperform the same experts.
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#### Estimator Calibration
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The book details the statistically observable tendency for people
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to underestimate risk and to be overconfident in their beliefs.
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It describes the process of "calibration"
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@@ -115,19 +130,9 @@ and make predictions far more accurately.
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See [[estimator-calibration]] for more.
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Experts tend to be good at creating heuristics,
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but do not apply them consistently in practice.
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> [!example]
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> Chapter 7 describes a study where individual experts
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> were shown to estimate risk differently for identical cases.
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Chapter 13 introduces the [Brier Score](https://en.wikipedia.org/wiki/Brier_score)
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as a method of evaluating the performance of an estimator,
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evaluated as the mean squared error of their forecasts.
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> [!example] p. 198
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> Models based on expert opinion consistently outperform the same experts.
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equal to the mean squared error of their forecasts.
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### Luck Looks Like Skill
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@@ -142,19 +147,21 @@ to overvalue competence and undervalue luck
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in the role of achieving improbable accomplishments
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as the "Red Baron effect".
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This the unstated other half of the **law of large numbers**,
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that improbable events become likely with increased sampling.
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This the unstated other half of the **law of large numbers**:
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improbable events become likely with increased sampling.
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How many success stories are simply cases of winning a coin flipping tournament?
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> How many success stories
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> are simply cases of winning a coin flipping tournament?
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### Qualitative Labels are Problematic
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> [!example] p. 170 (pp.)
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> Experts do not agree on the bounds of terms expressing probability.
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> "Likely" vs. "Very Likely"
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> Experts do not agree on the bounds of terms expressing probability
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> (e.g. "Likely" vs. "Very Likely").
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> [!example] p. 182 (pp.)
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> risk matrix type bucketing tends to inflate the significance of small risks.
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> risk matrix type bucketing
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> tends to inflate the significance of small risks.
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### There's Always Enough Data
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@@ -169,7 +176,7 @@ that any industry is so niche that
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data sufficient for quantitative models
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does not exist.
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> [!quote] Fallacy of Close Analogy - p.236
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> [!quote] Fallacy of Close Analogy (p.236)
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> ...the belief that unless two things are identical in every way,
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> nothing learned from one can be applied to the other.
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@@ -212,17 +219,26 @@ to dismiss quantitative methods as inappropriate for their industry-specific ris
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> and therefore chooses Car B.
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> The buyer is committing the _exsupero ursus_ fallacy.
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Based on this strawman it is clear Hubbard believes his detractors are _correct_
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This and the other false equivalence analogy
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that is the namesake of the fallacy show that,
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while Hubbard believes his detractors are _correct_
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that qualitative methods can not capture the entire nuance of risk probability,
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but that they are failing to acknowledge that their preferred alternatives
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he believes they are failing to acknowledge that their preferred alternatives
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are not demonstrably more effective at doing so.
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The nuance Hubbard dismisses without addressing
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is the possibility of model _improvement_.
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There is an obvious reason why a decision-maker
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might prefer a human expert over a heuristic algorithm,
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even if the algorithm is demonstrated
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to outperform the human in all relevant metrics:
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_Adaptability_.
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It's likely that this preference is demonstrably unreasonable in many or most cases,
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but that it isn't acknowledged severely weakens Hubbard's argument.
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A most competent detractor would be aware of the apparent contradiction
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but argue that their methods will eventually surpass quantitative methods
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if they are further developed.
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Such a position would additionally contextualize Hubbard's observations
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Such a position would also contextualize Hubbard's observations
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that detractors become emotional in their defense.
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To them, Hubbard's methods represent an attractive short-term gain
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that would exclude a long-term payoff.
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