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