Matlin, Ch. 12

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Matlin, Ch. 12
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Overconfidence effect

• Class demo estimating 90confidence intervals
  anchoring adjustment heuristic affects
  judgments
• Overconfidence believe own opinion despite
  data MF in overconfidence dont think of
  alternatives dont know how weak evidence is for
  own opinion confirmation bias

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• Anchoring adjustment decide what we think
  right answer is, then adjust tendency is not to
  adjust enough haggling over pricebe sure to
  anchor at low price, if buying high price if
  selling

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Class demo--heuristics

• Flight instructor problemregression to the mean
  similar to possible Sports Illustrated Jinx
• Linda is a bank teller active in feminist
  movement problemconjunction error believe that
  p(A and B) p(A) also example of
  representativeness heuristic

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Class demo--heuristics

• Base rate neglect--truck driver vs. Ivy League
  literature professor (also example of
  representativeness heuristic) cab problem
• Sample size likely event more certain with
  larger sample sizeurn filled with black white
  balls
• Sample size unlikely event more likely with
  small sample sizehospital boy vs. girl birth
  numbers

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Class demo--heuristics

• Framing effects problem stated as gain vs. loss
  and how decisions changeGenerals route choice
  (die vs. be saved) illness problem (surgery vs.
  radiation) gambling (sure gain vs. sure loss)
• Mental accountingconcert ticket problem

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More heuristics

• Representativenessadditional examples
• Randomly-generated samples should look random
  would you feel confident if your Lotto numbers
  were 1,2,3,4,5,6?
• Small-sample fallacy belief that pattern in
  small sample should be similar to that in large
  pattern

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Even more heuristics

• Availability heuristicfrequency judged by how
  easily example can be retrieved from memory
• Overestimation due to attention-getting
  events/objects noticed remembered more (e.g.,
  changed answers on teststend to notice ones
  changed from right to wrong more things
  meaningful or familiar to us better remembered

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Heuristics galore

• Availability (contd.)familiar names seem more
  numerous than unfamiliar names, in list with
  equal numbers of each
• Illusory correlationtend to recall info that
  confirms expected link between variables
• Simulation heuristicif it is easy to imagine, we
  judge it to be more likely

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Heuristics gone wild

• Seeing random patterns as meaningful the hot
  hand in basketball study clutch hitting in
  baseball role of availability heuristic
• Hindsight biasaltered memory of what we
  previously thought if we end up being correct,
  we remember being confident it would turn out
  that way if we are wrong, we decrease how
  confident we remember being previously

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• Doubling sheet of paper link
• http//raju.varghese.org/articles/powers2.html