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#### The Mind Of "Aces": Possible Causes And Consequences Of Overconfidence
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#### The Mind Of "Aces": Possible Causes And Consequences Of Overconfidence
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Unless managers take steps to offset overconfidence
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in assessments of probabilities,
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they will consistently underestimate various risks
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(i.e., they will be more confident than they should be
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that some disaster won't occur).
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This may have had some bearing on very-high-profile disasters,
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such as those of the Space Shuttle Orbiters *Challenger* and *Columbia*.
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The Nobel Prize-winning physicist, Richard Feynman,
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was asked to participate in the investigation of the first Space Shuttle accident
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(involving *Challenger*).
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What he found were some risk assessments that seemed at first glance to be obviously optimistic.
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He noted the following in the *Rogers Commission Report on the Space Shuttle* Challenger *Accident*:
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> It appears that there are enormous differences of opinion
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> as to the probability of a failure with loss of vehicle and of human life.
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> The estimates range from roughly 1 in 100 to 1 in 100,000.
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> The higher figures \[1 in 100\] come from the working engineers
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> and the very low figures \[1 in 100,000\] from management.
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> What are the causes and consequences of this lack of agreement?
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> Since 1 part in 100,000 would imply
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> that one could put a Shuttle up each day for 300 years
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> expecting to lose only one,
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> we could properly ask
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> "What is the cause of management's fantastic faith in the machinery?"[^7-10]
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Feynman believed that if management decisions to launch
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were based on such an extraordinary confidence in the Shuttle,
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then these decisions were flawed.
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As was Feynman's frequent practice,
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he applied simple tests and reality checks
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that would cast doubt on these claims.
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Perhaps an obvious explanation is the conflict of interest.
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Are managers really incentivized to be honest with themselves and others
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about these risks?
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No doubt, that is a factor,
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just as it was probably a factor in the assessments of risks
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taken by bank managers in 2008,
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whether or not it was consciously considered.
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However, individuals showed overconfidence
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even in situations when they had no stake in the outcome (trivia tests, etc.).
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JDM research has shown that both the incentives and the amount of effort put into identifying possible surprises will make a difference in overconfidence.[^7-11]
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Some of the sources of overconfidence would affect
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not only managers who depend on subjective estimates
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but also those who believe they are using sound analysis of historical data.
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Managers will fail to consider ways in which human errors affect systems and will fail to consider common mode and cascade system failures.[^7-12]
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There may also a tendency to relax our concerns
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for infrequent but catastrophic events
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when some time passes without experiencing the event.
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Robin Dillon-Merrill,
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a decision and risk analysis professor at Georgetown University,
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noticed this tendency when she was studying
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the risk perceptions of NASA engineers
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prior to the Space Shuttle *Columbia* accident.
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*The* Columbia *Accident Investigation Report* noted the following:
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> The shedding of External Tank foam---
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> the physical cause of the Columbia accident---had a long history.
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> Damage caused by debris has occurred on every Space Shuttle flight,
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> and most missions have had insulating foam shed during ascent.
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> This raises an obvious question:
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> Why did NASA continue flying the Shuttle
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> with a known problem that violated design requirements?[^7-13]
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Dillon-Merrill considers each time
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that foam fell off the external tank of the Shuttle,
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but where the Shuttle still had a successful mission,
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to be a "near miss."
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Her proposal was that near misses are an opportunity to learn
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that is rarely exploited.
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She interviewed NASA staff and contractors
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about how they judged near misses
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and found two very interesting phenomena
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that in my opinion have important implications
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for risk management in general.
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Perhaps not surprisingly, she found that near misses and successes
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were both judged much more favorably than failures.
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But were these near-miss events being rated more like a failure
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than a mission success?
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Did engineers take each near miss as a red flag warning
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about an impending problem?
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Incredibly, just the opposite occurred.
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The study included an experiment
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where NASA staff and students
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were asked to choose among various options
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for hypothetical unmanned space missions.
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The options included decisions like whether to skip a test
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due to schedule constraints.
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Some subjects were given near miss data and some were not.
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The study found that people with the near-miss information were *more* likely to choose the riskier alternative.[^7-14]
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> *The near miss interpretation paradox*:
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> People with near-miss information
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> were *more* likely to make the riskier choice
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> than people who did not have information about near misses.
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It is possible that managers were looking at each near miss
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and thinking that because nothing had happened yet,
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perhaps the system was more robust than they thought.
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Or it might be more subtle than that.
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Dillon-Merrill found that when people have a known exposure
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to some relatively unlikely risk,
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their tolerance for that risk seems to increase
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even though they may not be changing their estimate
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of the probability of the risk.
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Imagine that you are in an area exposed to hurricane risks.
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Authorities confirm that there is a 3 percent chance of injury or death
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each time you do not evacuate when ordered to for a hurricane warning.
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If you happen to make it through two or three hurricanes without harm,
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you will become more tolerant of that risk.
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Note that you are not actually changing your estimate
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of the probability of the harm
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(that was provided by authorities);
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you are simply becoming more numb to the risk as it is.
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Now imagine the implications of this for Wall Street.
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If they have a few good years,
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everybody will start to become more "risk tolerant"
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even if they are not changing their underlying forecasts
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about the probabilities of a financial crisis.
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Now that the mortgage uncertainty has settled for a decade or so,
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will all managers, again, start to become more tolerant of risks?
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There are other effects to consider
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when examining the psyche of upper-level decision-makers.
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Part of overestimating past performance
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is due to the tendency to underestimate how much we learned
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in the last big surprise.
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This is what Slovic and Fischhoff called the *I-knew-it-all-along* phenomenon.
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People will exaggerate how "inevitable" the event would have appeared
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before the event occurred.
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(News pundits talking about the mortgage crisis
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certainly make it sound as if it were inevitable,
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but where were they before the crisis occurred?)
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They even remember their previous predictions in such a way that they,
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as Slovic put it, "exaggerate in hindsight what they knew in foresight."
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I hear the I-saw-that-coming claim so often that, if the claims were true,
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there would be virtually no surprises anywhere in the world.
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Two lines of dialog in the movie *Wall Street*
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revealed Oliver Stone's grasp of this phenomenon.
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After "Bud" (Charlie Sheen's character) had his initial big successes as a broker,
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his boss said, "The minute I laid eyes on you, I knew you had what it took."
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Later, when Bud was being arrested in the office
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for the crimes he committed to get those early successes,
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the same boss said, "The minute I laid eyes on you, I knew you were no good."
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Kahneman sums it up:
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> When they have made a decision,
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> people don't even keep track of having made the decision or forecast.
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> I mean, the thing that is absolutely the most striking
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> is how seldom people change their minds.
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> First, we're not aware of changing our minds
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> even when we do change our minds.
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> And most people, after they change their minds,
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> reconstruct their past opinion---
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> they believe they *always* thought that.[^7-15]
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There is one other item about overconfidence
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that might be more unique to upper management
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or particularly successful traders.
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Some managers can point to an impressive track record of successes
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as evidence that a high level of confidence on virtually all matters
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is entirely justified on their part.
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Surely, if a portfolio manager can claim
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she had above-average market returns for five years,
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she must have some particularly useful insight into the market.
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An IT security manager who has presided over a virus-free,
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hacker-free environment much longer than his peers in other companies
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must have great skill, right?
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Actually, luck can have more to do with success
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than we might be inclined to think.
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For example, a statistical analysis of World War I aces
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showed that Baron von Richthofen (aka The Red Baron)
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might have been lucky but not necessarily skilled.[^7-16]
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Two electrical engineering professors,
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Mikhail Simkin and Vwani Roychowdhury
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of the University of California at Los Angeles,
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examined the victories and losses
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for the 2,894 fighter pilots who flew for Germany.
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Together, they tallied 6,759 victories and 810 defeats.
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This is perhaps a suspiciously high win ratio
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but these numbers include shooting down unarmed scout and delivery planes.
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The Germans also had a technological advantage in the air during WWI.
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Furthermore, not all kills could be confirmed
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and the inflation of these numbers is certainly possible---
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but there is no reason to assume
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that the Baron was less prone to exaggeration than others.
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Simkin and Roychowdhury showed that,
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given the number of pilots and the win ratio,
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there was about a 30 percent chance that, by luck alone,
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one pilot would have gotten eighty kills,
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the number Manfred von Richthofen is credited for.
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This might describe a large number of "successful" executives
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who write popular books on the special insight they brought to the table,
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but who then sometimes find they are unable to repeat their success.
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Given the large number of candidates
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who spend their careers competing
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for a small number of upper-management positions,
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it is likely that some will have a string of successes just by chance alone.
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No doubt, some of these will be more likely
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to hold upper-management positions.
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In the same manner,
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some will also have a string of successes in a coin-flipping tournament
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in which there are a large number of initial players.
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But we know that the winners of this kind of contest
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are not just better coin-flippers.
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Sure, there is probably some skill in reaching upper management.
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But how much of it was more like winning a coin-flipping contest?
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#### Inconsistencies And Artifacts: What Shouldn't Matter Does
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#### Inconsistencies And Artifacts: What Shouldn't Matter Does
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#### Answers To Calibration Tests
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#### Answers To Calibration Tests
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#### Notes
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#### Notes
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[^7-1]: D. Kahneman and G. Klein "Conditions for Intuitive Expertise: A Failure to Disagree," *American Psychologist* 64, no. 6 (2009): 515--26.
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[^7-2]: A. H Murphy and R. L Winker, "Can Weather Forecasters Formulate Reliable Probability Forecasts of Precipitation and Temperature?," *National Weather Digest* 2 (1977): 2--9.
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[^7-3]: D. Kahneman and A. Tversky, "Subjective Probability: A Judgment of Representativeness," *Cognitive Psychology* 3 (1972): 430--54.
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[^7-4]: G. S Tune, "Response Preferences: A Review of Some Relevant Literature," *Psychological Bulletin* 61 (1964): 286--302.
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[^7-5]: W. Feller, *An Introduction to Probability Theory and Its Applications* (New York: Wiley, 1968), 160.
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[^7-6]: E. Johnson, "Framing, Probability Distortions and Insurance Decisions," *Journal of Risk and Uncertainty* 7 (1993): 35.
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[^7-7]: D. Kahneman and A. Tversky, "Subjective Probability: A Judgment of Representativeness," *Cognitive Psychology* 4 (1972): 430--54.
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[^7-8]: D. Kahneman and A. Tversky, "On the Psychology of Prediction," *Psychological Review* 80 (1973): 237--51.
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[^7-9]: A. Tversky and D. Kahneman, "The Belief in the 'Law of Small Numbers,'" *Psychological Bulletin* 76 (1971): 105--10.
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[^7-10]: R. Feynman, "Personal Observations on the Reliability of the Shuttle," Appendix IIF. In William Rogers et al., *Space Shuttle Accident Report* (Washington, DC: US GPO, 1986).
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[^7-11]: A. Koriat, S. Lichtenstein, and B. Fischhoff, "Reasons for Confidence," *Journal of Experimental Psychology: Human Learning and Memory* 6 (1980): 107--18.
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[^7-12]: P. Slovic, B. Fischhoff, S. Lichtenstein, *Societal Risk Assessment: How Safe Is Safe Enough?* (New York: Plenum Press, 1980).
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[^7-13]: *The* Columbia *Accident Investigation Board Report*, Vol. I (Washington, DC: US GPO, 2003), 121.
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[^7-14]: R. Dillon and C. Tinsley, "How Near-Misses Influence Decision Making under Risk: A Missed Opportunity for Learning," *Management Science* 54, vol. 8 (January 2008): 1425--40.
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[^7-15]: M. Schrage, "Daniel Kahneman: The Leader Interview," *strategy + business*, <https://www.strategy-business.com/article/03409?gko=7a903%2031.12.2003>.
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[^7-16]: M. Simkin and V. Roychowdhury, "Theory of Aces: Fame by Chance or Merit?," *Journal of Mathematical Sociology* 30, no. 1 (2006): 33--42.
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[^7-17]: E. Brunswik, "Representative Design and Probabilistic Theory in a Functional Psychology," *Psychological Review* 62 (1955): 193--217.
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[^7-18]: C. M Kuhnen and B. Knutson, "The Neural Basis of Financial Risk Taking," *Neuron*, 47 (2005): 763--70.
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[^7-19]: P. Aldhous, "Cheery Traders May Encourage Risk Taking," *New Scientist* (April 7, 2009).
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[^7-20]: Paolo Sapienza, Luigi Zingales, and Dario Maestripieri, "Gender Differences in Financial Risk Aversion and Career Choices Are Affected by Testosterone," *Proceedings of the National Academy of Sciences of the United States of America* 106, no. 36 (2009).
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[^7-21]: J. S Lerner and D. Keltner, "Fear, Anger, and Risk," *Journal of Personality & Social Psychology* 81, no. 1 (2001): 146--59.
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### Chapter 8: Worse Than Useless: The Most Popular Risk Assessment Method And Why It Doesn't Work
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### Chapter 8: Worse Than Useless: The Most Popular Risk Assessment Method And Why It Doesn't Work
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#### A Few Examples Of Scores And Matrices
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#### A Few Examples Of Scores And Matrices
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@@ -295,7 +556,8 @@ In addition to Kahneman,
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it is worth pointing out others whose work Taleb cites to make a point but who,
|
it is worth pointing out others whose work Taleb cites to make a point but who,
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if you actually looked at what they are doing, would contradict Taleb.
|
if you actually looked at what they are doing, would contradict Taleb.
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For example, Taleb says he admires the mathematician Edward Thorp,
|
For example, Taleb says he admires the mathematician Edward Thorp,
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who developed a mathematically sound basis for card counting in blackjack in the 1960s.
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who developed a mathematically sound basis
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for card counting in blackjack in the 1960s.
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Now, if the objective of card counting was to predict every hand,
|
Now, if the objective of card counting was to predict every hand,
|
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even the most extraordinarily rare combinations as Taleb would seem to require,
|
even the most extraordinarily rare combinations as Taleb would seem to require,
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then Ed Thorp's method certainly fails.
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then Ed Thorp's method certainly fails.
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@@ -330,12 +592,15 @@ and does so in many trials not just single anecdotes.
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Finally, Taleb makes the error of presuming what methods
|
Finally, Taleb makes the error of presuming what methods
|
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were actually being used when he blames them for an event.
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were actually being used when he blames them for an event.
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He argues, for example,
|
He argues, for example,
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that the downfall of long-term capital management (LTCM) disproves options theory.
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that the downfall of long-term capital management (LTCM)
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Recall that options theory won the Nobel Prize for Robert Merton and Myron Scholes,
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disproves options theory.
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Recall that options theory won the Nobel Prize
|
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for Robert Merton and Myron Scholes,
|
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both of whom were on the board of directors for LTCM.
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both of whom were on the board of directors for LTCM.
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The theory was presumably the basis of the trading strategy of the firm.
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The theory was presumably the basis of the trading strategy of the firm.
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But an analysis of the failure of LTCM shows that a big reason for its downfall
|
But an analysis of the failure of LTCM shows that a big reason for its downfall
|
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was the excessive use of leverage in trades---an issue that isn't even part of options theory.
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was the excessive use of leverage in trades---
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an issue that isn't even part of options theory.
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That appeared to be based on intuition.
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That appeared to be based on intuition.
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Taleb also states that the crash of 1987 disproved modern portfolio theory (MPT),
|
Taleb also states that the crash of 1987 disproved modern portfolio theory (MPT),
|
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@@ -348,7 +613,8 @@ but 'real-world' decisions have to be based on practical experience, too."
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In fact, I found no fund managers who didn't rely partly, if not mostly, on intuition.
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In fact, I found no fund managers who didn't rely partly, if not mostly, on intuition.
|
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Finally, if we are looking for explanations of the mortgage crisis,
|
Finally, if we are looking for explanations of the mortgage crisis,
|
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neither MPT nor options theory had anything to do with the practice
|
neither MPT nor options theory had anything to do with the practice
|
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of giving out mortgages to large numbers of people lacking the ability to pay them.
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of giving out mortgages to large numbers of people
|
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lacking the ability to pay them.
|
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That was more of a function of a system
|
That was more of a function of a system
|
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that incentivized banks to give risky loans without actually accepting the risk.
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that incentivized banks to give risky loans without actually accepting the risk.
|
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@@ -358,9 +624,11 @@ he ends up undermining the point he makes.
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For example, explaining the outcomes
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For example, explaining the outcomes
|
||||||
in terms of the narrative fallacy committed by others
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in terms of the narrative fallacy committed by others
|
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is sometimes itself a narrative fallacy.
|
is sometimes itself a narrative fallacy.
|
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Arguing that "experts" don't know so much is not supported by quoting other experts.
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Arguing that "experts" don't know so much
|
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is not supported by quoting other experts.
|
||||||
He argues that rare events defy quantitative models,
|
He argues that rare events defy quantitative models,
|
||||||
but then gives specific examples of computing rare events with quantitative models
|
but then gives specific examples
|
||||||
|
of computing rare events with quantitative models
|
||||||
(he shows the odds of getting the same result in a coin flip many times in a row
|
(he shows the odds of getting the same result in a coin flip many times in a row
|
||||||
and argues the benefits of Mandelbrot's mathematical models
|
and argues the benefits of Mandelbrot's mathematical models
|
||||||
in the analysis of market fluctuations).
|
in the analysis of market fluctuations).
|
||||||
@@ -387,7 +655,8 @@ we find how often naive historical analysis can be wrong.
|
|||||||
|
|
||||||
Taleb's own "experience," as extensive as it might be (at least in finance),
|
Taleb's own "experience," as extensive as it might be (at least in finance),
|
||||||
is also just a historical analysis---just a very informal type
|
is also just a historical analysis---just a very informal type
|
||||||
with lots of errors in both recall and analysis, as shown in [chapter 7].
|
with lots of errors in both recall and analysis,
|
||||||
|
as shown in [[#Chapter 7 The Limits Of Expert Knowledge Why We Don't Know What We Think We Know About Uncertainty|chapter 7]].
|
||||||
No thinking person can ever honestly claim
|
No thinking person can ever honestly claim
|
||||||
to have formed any idea totally independent of previous observations.
|
to have formed any idea totally independent of previous observations.
|
||||||
It just doesn't happen.
|
It just doesn't happen.
|
||||||
@@ -400,7 +669,8 @@ Of course, Taleb is right when he says we shouldn't _assume_
|
|||||||
that we have defined any problem perfectly.
|
that we have defined any problem perfectly.
|
||||||
That certainly would be an error, and if that were Taleb's point, that would be valid.
|
That certainly would be an error, and if that were Taleb's point, that would be valid.
|
||||||
But, again, whether a particular model is perfect is not the right question.
|
But, again, whether a particular model is perfect is not the right question.
|
||||||
The most relevant question is whether a probabilistic model---even a simple one---
|
The most relevant question is whether a probabilistic model---
|
||||||
|
even a simple one---
|
||||||
outperforms the alternative model, such as intuition.
|
outperforms the alternative model, such as intuition.
|
||||||
|
|
||||||
#### Major Mathematical Misconceptions
|
#### Major Mathematical Misconceptions
|
||||||
@@ -538,6 +808,225 @@ and if we are adding detail where it informs decisions most.
|
|||||||
|
|
||||||
#### Simple Risk Management
|
#### Simple Risk Management
|
||||||
|
|
||||||
|
We've talked about introducing the very basics of quantitative risk analysis.
|
||||||
|
Now we need to turn that basic risk analysis
|
||||||
|
into a basic risk management framework.
|
||||||
|
When you've completed your initial list of risks,
|
||||||
|
you will want to compare your LEC to the risk tolerance curve.
|
||||||
|
This tells you whether your current risk is acceptable,
|
||||||
|
but it is not the whole story.
|
||||||
|
|
||||||
|
You also need to determine which risk mitigations to employ
|
||||||
|
to reduce risk further.
|
||||||
|
If a mitigation reduces a particular risk by about 50 percent
|
||||||
|
but costs \$200,000, is it worth it?
|
||||||
|
As mentioned in [[#Chapter 4 Getting Started A Simple Straw Man Quantitative Model|chapter 4]],
|
||||||
|
this requires knowing our return on mitigation (RoM).
|
||||||
|
RoM is similar to a return on investment but for risk mitigations.
|
||||||
|
To compute this we need to work out a monetized risk
|
||||||
|
so that we can monetize the reduction of risk.
|
||||||
|
Then we could use RoM together with the LEC and the risk tolerance curve
|
||||||
|
as shown in [Exhibit 11.2].
|
||||||
|
|
||||||
|
To *mitigate* a risk is to moderate or alleviate a risk---to lessen it in some way.
|
||||||
|
Higher risks may be deliberately accepted for bigger opportunities
|
||||||
|
but even in those cases
|
||||||
|
decision-makers will not want to accept more risk than is necessary.
|
||||||
|
It is common in risk management circles
|
||||||
|
to think of a choice among four basic alternatives
|
||||||
|
for managing a given risk:
|
||||||
|
|
||||||
|
* **Avoid:**
|
||||||
|
We can choose not to take an action
|
||||||
|
that would create an exposure of some kind.
|
||||||
|
We can avoid the merger, the new technology investment,
|
||||||
|
the subprime mortgage market, and so on.
|
||||||
|
This effectively makes that particular risk zero
|
||||||
|
but might increase risks in other areas
|
||||||
|
(e.g., the lack of taking risks in R&D investments
|
||||||
|
might make a firm less competitive).
|
||||||
|
|
||||||
|
* **Reduce:**
|
||||||
|
The manager goes ahead with the investment
|
||||||
|
or other endeavors that have some risks
|
||||||
|
but takes steps to lessen them.
|
||||||
|
The manager can decide to invest in the new chemical plant
|
||||||
|
but implement better fire-safety systems
|
||||||
|
to address a major safety risk.
|
||||||
|
|
||||||
|
* **Transfer:**
|
||||||
|
The manager can give the risk to someone else.
|
||||||
|
Insurance is the best example of this.
|
||||||
|
The manager can buy insurance
|
||||||
|
without necessarily taking other steps to lessen the risk of the event
|
||||||
|
(e.g., buying fire insurance instead of investing
|
||||||
|
in advanced fire-prevention systems).
|
||||||
|
Risk can also be transferred to customers
|
||||||
|
or other stakeholders by contract
|
||||||
|
(e.g., a contract that states,
|
||||||
|
"The customer agrees that the company is not responsible for...").
|
||||||
|
|
||||||
|
* **Retain:**
|
||||||
|
This is the default choice for any risk management.
|
||||||
|
You simply accept the risk as it is.
|
||||||
|
|
||||||
|
I, and some risk managers I know,
|
||||||
|
find the boundaries between these a little murky.
|
||||||
|
A transfer of risk is a reduction or avoidance of risk
|
||||||
|
to the person transferring it away.
|
||||||
|
A reduction in risk is really the avoidance of particular risks
|
||||||
|
that are components of a larger risk.
|
||||||
|
The ultimate objective of risk management should be, after all,
|
||||||
|
the reduction of the total risk to the firm for a given expected return,
|
||||||
|
whether through the transfer or avoidance of risks
|
||||||
|
or the reduction of specific risks.
|
||||||
|
If total risk is merely retained,
|
||||||
|
then it may be no different from not managing risks at all.
|
||||||
|
|
||||||
|
##### Risk Mitigation
|
||||||
|
|
||||||
|
Y. S. Kong was the treasurer and chief strategic planner
|
||||||
|
at the HAVI Group in Illinois,
|
||||||
|
a consortium of major distribution service companies
|
||||||
|
operating in forty countries.
|
||||||
|
Y. S. prefers to categorize risk management activities
|
||||||
|
by specific risk mitigation actions he calls *risk filters*.
|
||||||
|
"We have four sequential 'risk filters':
|
||||||
|
transference, operational, insurance, and retention," explains Y. S.
|
||||||
|
The first preference is to transfer risks to customers or suppliers
|
||||||
|
through their contracts.
|
||||||
|
The second filter---operational---
|
||||||
|
is to address risks through better systems, procedures, roles, and so on.
|
||||||
|
The third filter is to insure the risk (technically, this is also transferring risks).
|
||||||
|
Finally, the retention of risk is not so much a filter,
|
||||||
|
but where the other risks land if they don't get filtered out earlier.
|
||||||
|
Even so, Y. S. as the treasurer
|
||||||
|
is tasked with ensuring they have an adequate asset position
|
||||||
|
to absorb any risk that ends up in this final bucket.
|
||||||
|
|
||||||
|
In the following list, I added a couple of items to Y. S.'s list
|
||||||
|
and expanded on each of them to make it as general as possible.
|
||||||
|
Unlike HAVI's risk filters, the order of this list does not imply a prescribed priority.
|
||||||
|
Note that this is a long, but still partial, list of risk mitigation alternatives:
|
||||||
|
|
||||||
|
* **Selection processes for major exposures:**
|
||||||
|
This is the analysis of decisions that create new sources of potential losses
|
||||||
|
to ensure that the risk being taken is justified by the expected reward.
|
||||||
|
For example:
|
||||||
|
|
||||||
|
* Risk/return analysis of major investments technology,
|
||||||
|
new products, and so on
|
||||||
|
|
||||||
|
* Selection of loan risks for banks;
|
||||||
|
accounts receivable risks for other types of firms
|
||||||
|
|
||||||
|
* **Insurance:**
|
||||||
|
This comes in dozens of specialized categories,
|
||||||
|
but here are a few of the many general groups:
|
||||||
|
|
||||||
|
* Insurance against loss of specific property and other assets,
|
||||||
|
including fire, flood, and so on
|
||||||
|
|
||||||
|
* Various liabilities, including product liability
|
||||||
|
|
||||||
|
* Insurance for particular trades or transportation of goods,
|
||||||
|
such as marine insurance or the launch of a communications satellite
|
||||||
|
|
||||||
|
* Life insurance for key officers
|
||||||
|
|
||||||
|
* Reinsurance, generally purchased by insurance companies,
|
||||||
|
to help risks that may be concentrated in certain areas
|
||||||
|
(e.g., hurricane insurance in Florida,
|
||||||
|
earthquake insurance in California, etc.)
|
||||||
|
|
||||||
|
* **Contractual risk transfer:**
|
||||||
|
Business contracts include various clauses
|
||||||
|
such as "*X* agrees the company is not responsible for *Y*,"
|
||||||
|
including contracts with suppliers, customers, employees, partners,
|
||||||
|
or other stakeholders.
|
||||||
|
|
||||||
|
* **Operational risk reduction:**
|
||||||
|
This includes everything a firm might do internally
|
||||||
|
through management initiatives to reduce risks, including the following:
|
||||||
|
|
||||||
|
* Safety procedures
|
||||||
|
* Training
|
||||||
|
* Security procedures and systems
|
||||||
|
* Emergency/contingency planning
|
||||||
|
* Investments in redundant and/or high-reliability processes,
|
||||||
|
such as multiple IT operations sites, new security systems, and so on
|
||||||
|
|
||||||
|
* Organizational structures or roles
|
||||||
|
defining clear responsibilities for and authority over
|
||||||
|
certain types of risks
|
||||||
|
(a shift safety officer, a chief information security officer, etc.)
|
||||||
|
|
||||||
|
* **Liquid asset position:**
|
||||||
|
This is the approach to addressing the retention of risk
|
||||||
|
but still attempting to absorb some consequences
|
||||||
|
by using liquid reserves (i.e., cash, some inventory, etc.)
|
||||||
|
to ensure losses would not be ruinous to the firm.
|
||||||
|
|
||||||
|
* **Compliance remediation:**
|
||||||
|
This is not so much its own category of risk mitigation
|
||||||
|
because it can involve any combination of the previously mentioned items.
|
||||||
|
But it is worth mentioning
|
||||||
|
simply because it is a key driver for so much of current risk mitigation.
|
||||||
|
This is, in part, a matter of "crossing the *t*'s and dotting the *i*'s"
|
||||||
|
in the growing volume of regulatory requirements.
|
||||||
|
|
||||||
|
* **Legal structure:**
|
||||||
|
This is the classic example of limiting liability of owners
|
||||||
|
by creating a corporation.
|
||||||
|
But risk mitigation can take this further even for existing firms
|
||||||
|
by compartmentalizing various risks
|
||||||
|
into separate corporate entities as subsidiaries,
|
||||||
|
or for even more effective insulation from legal liability,
|
||||||
|
as completely independent spin-offs.
|
||||||
|
|
||||||
|
* **Activism:**
|
||||||
|
This is probably the rarest form of risk mitigation
|
||||||
|
because it is practical for relatively few firms, but it is important.
|
||||||
|
Successful efforts to limit liabilities for companies in certain industries
|
||||||
|
have been won by advocating new legislation.
|
||||||
|
Examples are the Private Securities Litigation Reform Act of 1995,
|
||||||
|
which limits damage claims against securities firms;
|
||||||
|
Michigan's 1996 FDA Defense law,
|
||||||
|
which limits product liability for drugs that were approved by the FDA;
|
||||||
|
and the Digital Millennium Copyright Act of 1998,
|
||||||
|
which limits the liability of firms that provide a conduit
|
||||||
|
for the transmission of data from damages
|
||||||
|
that may be caused by the sources of the data.
|
||||||
|
|
||||||
|
As always, an informed risk mitigation starts with an identification
|
||||||
|
and then some kind of assessment of risks.
|
||||||
|
Once a risk manager knows what the risks are,
|
||||||
|
steps can be taken to address them in some way.
|
||||||
|
It might seem that some extremely obvious risks
|
||||||
|
can be managed without much of an assessment effort
|
||||||
|
(e.g., implementing full backup and recovery
|
||||||
|
at a data center that doesn't have it,
|
||||||
|
installing security systems at a major jewelry store, etc.).
|
||||||
|
But in most environments, there are numerous risks,
|
||||||
|
each with one or more potential risk mitigation strategies
|
||||||
|
and a limited number of resources.
|
||||||
|
We have to assess not only the initial risks
|
||||||
|
but also how much the risk would change
|
||||||
|
if various precautions were taken.
|
||||||
|
Then those risk mitigation efforts, once chosen,
|
||||||
|
have to be monitored in the same fashion
|
||||||
|
and the risk management cycle can begin again (see [exhibit 11.3]).
|
||||||
|
Notice that the assessment of risks appears prior to
|
||||||
|
and as part of the selection of risk mitigation methods.
|
||||||
|
|
||||||
|
Now, getting this far should be an improvement over unaided gut feel
|
||||||
|
and a big improvement over methods such as the risk matrix
|
||||||
|
or qualitative scoring methods.
|
||||||
|
Of course, this approach still makes many and big, simplifying assumptions.
|
||||||
|
In [[#Chapter 12 Improving The Model|chapter 12]],
|
||||||
|
we will review some issues worth considering
|
||||||
|
when you are ready to add more realism to the model.
|
||||||
|
|
||||||
#### Notes
|
#### Notes
|
||||||
|
|
||||||
### Chapter 12: Improving The Model
|
### Chapter 12: Improving The Model
|
||||||
|
|||||||
@@ -111,11 +111,11 @@ This the unstated other half of the **law of large numbers**
|
|||||||
|
|
||||||
#### Red Baron Effect
|
#### Red Baron Effect
|
||||||
|
|
||||||
> [!cite] Chapter 7 p.154 (pp.)
|
> [!quote] [[hubbard_2020_failure#Chapter 7 The Limits Of Expert Knowledge Why We Don't Know What We Think We Know About Uncertainty]]
|
||||||
> Hubbard describes a study which concluded that,
|
> ...given the number of pilots and the win ratio,
|
||||||
> given the number of German pilots and their overall victory/defeat figures,
|
> there was about a 30 percent chance that, by luck alone,
|
||||||
> there was a ~30% chance an individual would achieve The Red Baron's record
|
> one pilot would have gotten eighty kills,
|
||||||
> _by luck alone_.
|
> the number Manfred von Richthofen is credited for.
|
||||||
|
|
||||||
That is, there is a 30% chance The Red Baron was a [[lucky-fools|lucky fool]]
|
That is, there is a 30% chance The Red Baron was a [[lucky-fools|lucky fool]]
|
||||||
|
|
||||||
|
|||||||
@@ -0,0 +1,33 @@
|
|||||||
|
---
|
||||||
|
id: 2026-05-29T17:19:37-0400
|
||||||
|
title: 2026-05-29 17:19:37
|
||||||
|
tags: []
|
||||||
|
daily: "[[2026-05-29]]"
|
||||||
|
---
|
||||||
|
# 2026-05-29 17:19:37
|
||||||
|
|
||||||
|
I suspect that in general of [[conest]],
|
||||||
|
our assemblies are not intended to have fluff built in,
|
||||||
|
or that our preferred methods
|
||||||
|
are intended to include more material than necessary.
|
||||||
|
We prefer to tolerate the uncertainty, to retain the risk,
|
||||||
|
weighing it less than that of committing additional resources
|
||||||
|
to mitigation (estimating).
|
||||||
|
|
||||||
|
[[hubbard_2020_failure#Simple Risk Management]]
|
||||||
|
is perhaps the single most important section of Hubbard's
|
||||||
|
for breaking free of the confines of [[orthodox-construction-estimating]].
|
||||||
|
|
||||||
|
> It might seem that some extremely obvious risks
|
||||||
|
> can be managed without much of an assessment effort
|
||||||
|
> (e.g., implementing full backup and recovery
|
||||||
|
> at a data center that doesn't have it,
|
||||||
|
> installing security systems at a major jewelry store, etc.).
|
||||||
|
> But in most environments, there are numerous risks,
|
||||||
|
> each with one or more potential risk mitigation strategies
|
||||||
|
> and a limited number of resources.
|
||||||
|
> We have to assess not only the initial risks
|
||||||
|
> ==but also how much the risk would change==
|
||||||
|
> ==if various precautions were taken.==
|
||||||
|
|
||||||
|
Detailed takeoff is poor risk mitigation.
|
||||||
Reference in New Issue
Block a user