Rationality

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Rationality IrrationalityorWhy are we so
foolish,and what can we do about it?
Present company excepted, of course.
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Rationality Irrationality

• Why are we so foolish?
• The rise and fall of rationality on cognitive
  science
• An introduction to inevitable illusions
• What can we do it about our foolishness?

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• It has been said that man is a rational
  animal. All my life I have been searching for
  evidence which could support this.
• --Bertrand Russell / An Outline
  of Intellectual Rubbish

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The rise and fall of human rationality

• (Some proponents of) Cognitive science had high
  hopes of being a science of ideal rationality
  when it emerged
• The cleave between competence (computation) and
  performance (biology)
• This goal was stymied by evidence of
• Lack of general problem-solving methods
• (Over-)Compartmentalization of knowledge
• Context effects
• A growth industry in the study of systematic
  human foolishness Cognitive illusions

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The rise and fall of rationality on cognitive
science

• Why should this be so?

If no organic being excepting man had
possessed any mental power, or if his powers had
been of a wholly different nature from those of
the lower animals, then we should never have been
able to convince ourselves that our high
faculties had been gradually developed. But it
can be shewn that there is no fundamental
difference of this kind. We must also admit that
there is a much wider interval in mental power
between one of the lowest fishes, as a lamprey or
lancelet, and one of the higher apes, than
between an ape and man yet this interval is
filled up by numberless gradations. Charles
Darwin/ The Descent Of Man
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• The brain is constructed to find reward in
  apparent solutions (coherence) which are not the
  same as solutions (cf. Damasio, Cytowic, Bernard
  not to mention those old philosophers, Ludwig
  Wittgenstein Charles Peirce)

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Psychopaths could be best financial traders?

• This was a Reuters headline on September 19,
  2005
• In a study of investors' behavior 41
  people with normal IQs were asked to play a
  simple investment game. Fifteen of the group had
  suffered lesions on the areas of the brain that
  affect emotions.
• The result was those with brain
  damage outperformed those without.
• The scientists found emotions led
  some of the group to avoid risks even when the
  potential benefits far outweighed the losses, a
  phenomenon known as myopic loss aversion.

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• Objective statistical frequency is one thing
  the facility with which our imagination
  represents certain events or situations, and our
  emotional impressionability, are quite another.
• Any probabilistic intuition by anyone not
  specifically tutored in probability calculus has
  a greater than 50 percent chance of being wrong.
• M. Piattelli-Palmarini Inevitable Illusions

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Cognitive Illusion 1 Over-confidence

• We are not good at judging our own confidence
  levels
• We tend to systematically err on the high side,
  and to resist attempts at correction
• The error increases as we become more certain
• We institutionalize this error by demanding
  certainty from our experts and instilling
  certainty in them
• Question Are there any good reasons to make this
  demand?

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Cognitive Illusion 1 Over-confidence

• Fischoff, Slovic, Lichenstein (1977) Knowing
  with Certainty The Appropriateness of Extreme
  Confidence
• Asked subjects to answer factual questions and
  rate their certainty on the answers
• For example
• The potato came from Ireland / Peru
• Kahlil Gibran was inspired by Buddhism /
  Christianity
• More people die from All accidents / Heart
  attacks
• A rational probability approach would tie
  certainty to what measure?

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Cognitive Illusion 1 Over-confidence

• In fact, subjects judged their certainty
  extremely high, with probabilities of being wrong
  as low as one in a thousand or even one in a
  million
• This implies that they expected they would be
  erroneous only one out of every thousand or
  million questions asked (and that they consider
  10001 odds that they are wrong as a fair bet)

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Cognitive Illusion 1 Over-confidence

• This over-confidence remained even when subjects
  were debiased by extensive tutoring about
  probability
• The bias was increased when difficult questions
  were removed, so that subjects had more knowledge
• cf My friend Jim and I in the Lets Make A Deal
  game
• The more knowledgeable (and therefore accurate) a
  person is, the more their over-confidence
  increases

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Cognitive Illusion 2 Magical thinking

• We put great confidence in signs that derive from
  folk beliefs illusory correlations
• We will see some worrisome evidence of this in a
  later reading in this class
• Moreover, we look for evidence to support and
  sustain an priori beliefs in correlations
• We are easily taught to do so, even in the
  absence of evidence or the presence of
  counter-evidence
• Cancer cell recognition Watzlawick

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Cognitive Illusion 2 Magical thinking

• If you have a cold, should you keep warm?
• If you are against sugar, should you drink fruit
  juice instead of pop?
• Is there any reason not to swim after eating?
• Is a black cat bad luck?
• Is it a sign from the heavens if it is sunny on
  the day you are wed (cf. Pierre Trudeaus wife)?

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Cognitive Illusion 2 Magical thinking

• One specific problem is that we tend to
  over-focus on true positive cases that is, if
  A and B sometimes co-occur, that is good enough
  for us to say they always go together
• If two things always go together, then we can
  deduce one from the other
• So humans tend to make mistakes that mix up
  correlation with causation or identity, often due
  to a failure to understand probability
• Frontal lobe spiking during sleep, and epilepsy
  at the University Hospital

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Cognitive Illusion 2 Magical thinking

• A famous case (Wason Johnson-Laird)
• Which of four cards. with a drawing on one side
  and a diagnosis on the other, do we need to turn
  over to see if people suffering form persecution
  delusions always make drawings with large eyes?
• Card 1 A diagnosis of persecution mania.
• Card 2 A diagnosis of something else
• Card 3 A drawing with large eyes
• Card 4 A drawing with normal eyes.

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Cognitive Illusion 3 20/20 Hindsight

• The fact that something actually has happened is
  taken to mean that
• It had a high probability (or, more likely,
  certainty) of happening
• That we could/should have known this beforehand
• This is commonly seen in good and bad fortune
• I knew I was going to win before I pulled the
  slot machine arm.
• I always had a bad feeling about that guy you
  just dumped.

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Cognitive Illusion 4 Anchoring

• We use initial reference points to anchor future
  estimates
• We do so even when those initial reference points
  are (known to be) random
• eg. The answer to How many African countries in
  the UN? is demonstrably influenced by randomly
  spinning a wheel in view of the subject

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Cognitive Illusion 4 Anchoring

• Anchoring is commonly used in obtaining
  confessions if a person is accused of enough
  outrageous crimes, they are more likely to admit
  to lesser crimes

• Capturing The Friedmans as a psychometric
  exercise

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Cognitive Illusion 4 Anchoring

• Anchoring is also used by propagandists by
  downplaying bad things and up-playing good
  things, they get people to change the set-point
• The articles gives an example from Bush, Sr.,
  whose Gulf War killed hundreds of thousands of
  Iraqis
• Bush, Jr. learned from his Daddy How many Iraqi
  civilians have been killed in the current Iraqi
  invasion? How many US soldiers are dead?

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Cognitive Illusion 4 Anchoring

• The same things is commonly used in advertising
  Compare at 99!
• You can also use it in bargaining Start really
  high when selling and stupidly low when buying
• It also accounts for first impressions and the
  huge efforts we go to to manage them (e.g.
  wearing a suit for a job interview!)
• Think of people who happened to be drunk when you
  first met them

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Cognitive Illusion 5 Availability Taking the
easy way out

• We will use an easier representation rather than
  a more complex one
• The easier it is to bring an event to mind, the
  more likely we are to judge it as frequent (Uncle
  Georges Pancakes fallacy)
• This leads to under-estimation of what is
  frequent (suicide) and over-estimation of what is
  not (murder child abduction), and thereby
  mis-estimations of coincidence

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Cognitive Illusion 5 Availability Taking the
easy way out

• The ease may be emotional More emotional
  things are more available
• ERP evidence shows that depressives find negative
  statements less anomalous than non-depressed
  subjects do
• It may also be focused-based Colleagues who
  perform well may assume that no one else did we
  see hot streaks in players or games we follow
  but not in others

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Cognitive Illusion 5 Availability Taking the
easy way out

• Homework Pick a random number (under 100 is
  best) and be ready for coincidences in everyday
  life about it. Report back to us.
• 23 is a perennial favorite See Wikipedia 23
  Enigma

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Cognitive Illusion 5 Availability Taking the
easy way out

• How to make yourself miserable A case study

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Cognitive Illusion 6 Probability blindness

• We dont equate equal probabilities (although the
  Gods do!), especially at the extremes of the
  probability range
• We prefer an increase from 0.94 to 0.99 from one
  to 0.38 to 0.42, or something which reduces risk
  from 0.001 to 0 to something which reduces it
  from 0.002 to 0.001
• We reduce probabilities to certainties
• We deny that population probabilities apply to
  individual cases (Marcel Duchamp After all,
  its always the others who die.)
• We mis-estimate co-variation ---gt

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Covariation mis-estimation
From Arkes, Harkness, Biber (1980)
Question How strong is the relation between
symptom X and death? (How worried should you be,
on a scale of 1-100, if you have symptom X?)
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Cognitive Illusion 7 Story-telling(Reconsiderati
on under suitable scripts)

• We over-estimate the probability of coherent
  fictions with many parts (conjunction illusion)
• E.g. Subjects estimate that it is more likely
  that the USSR would invade Poland the US would
  subsequently withdraw its Soviet ambassador than
  that one or the other would happen
• But chains of events must be less probable than
  their weakest link (assuming we have no absolute
  certainty, which we never do).

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Cognitive Illusion 7 Story-telling(Reconsiderati
on under suitable scripts)

• Both research and real life observation tell us
  that people find arguments more compelling when
  they support what they already believe anyway.
• Or they alter the story to fit what the believe
• E.g. Q Why would God do insert seemingly
  unlikely Deistic behavior here? A To test our
  faith.

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• Or they alter the story to fit what the believe
• I admire especially a certain prophetess
  who lived beside a lake in Northern New York
  State about the year 1820. She announced to her
  numerous followers that she possessed the power
  of walking on water, and that she proposed to do
  so at 11 o'clock on a certain morning. At the
  stated time, the faithful assembled in their
  thousands beside the lake. She spoke to them,
  saying "Are you all entirely persuaded that I
  can walk on water?" With one voice they replied
  "We are." "In that case," she announced, "there
  is not need for me to do so." And they all went
  home much edified.
• Bertrand Russell
• An Outline of Intellectual Rubbish
• See also Penn Tellers Indian Rope Trick.

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Cognitive Illusion 7 Story-telling(Reconsiderati
on under suitable scripts)

• Story-telling is related to 20/20 hindsight we
  can build hindsight by telling quasi-coherent
  stories
• Beware, politicians also know and use this
  illusion! a few years ago they had a few hundred
  million people believing it was sane to bomb Iraq
  because of 9-11, despite the fact that no Iraqis
  were involved in 9-11!

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What can we do about our foolishness?

• 1.) Distrust certainty Cultivate scepticism
  joyously
• Doubt is an uncomfortable condition, but
  certainty is a ridiculous one. - Voltaire
• The believer is happy the doubter is wise.
• - Greek Proverb
• 2.) Keep score Dont rely on your memory.
• - Keep clinical records, compile databases
  consult them before you act.
• 3.) Do the math.
• - Use Bayes Theorem run statistical tests
  look at distribution shapes etc.

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What can we do about our foolishness? II

• 4.) Consider many plausible alternatives
• - Research shows that this reduces hind-sight
  bias in some cases (re. Availability)
• 5.) Watch out for the buddy-buddy syndrome
• The cognitive degradation and feckless
  vocalization characteristic of committees are too
  well-known to require comment. - Paul Meehl

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What can we do about our foolishness? III

• 6.) Dont weight all evidence equally ignore
  irrelevancies
• - Evidence must be differentially relevant
  (distinguish between actual possibilities) to be
  considered
• - Barnum statements True of practically
  everyone.
• 7.) Distinguish between inclusion and exclusion
  criteria
• - Failure to have an accessory symptom of X is
  not evidence against a diagnosis of X
• 8.) Remember reliability bounds
• - An insignificant difference on a test result
  is insignificant

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What can we do about our foolishness? IV

• 9.) Dont mistake soft-headedness for
  soft-heartedness
• 10.) Be courageous Speak up for rationality!
• - Dont be cowed by people who havent read or
  understood Bayes Theorem etc.
• - Insist on doing your job the right way, and
  dont back down.

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• Questions etc.
• Coincidence example from Piatelli-Palmarini How
  many people need we have in a room to have a 50
  chance that two have the same birthday?
• Is rationality always best?
• What is the role of authoritarianism in affecting
  perceptual and moral judgments?
• What is the effect of these inevitable illusions
  in todays world of mass media? (Why might the
  WWW both hinder and help rational analysis of
  probabilities?)
• How can we harness these illusions to foster
  individual well being and social harmony (without
  also fostering harmful delusion)?