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To help students improve their thinking about:
Is improvement needed?
Is improvement possible?
Students should learn to:
For textbooks, readings, requirements, see syllabus.
Lecture notes will be posted on the course Web site each week.
An error tendency is a pattern of thinking that is natural for people but frequently leads to errors in judgments about what to believe or decisions about what to do.
Psychologists such as Gilovich often discuss error tendencies in terms of heuristics (rules of thumb in thinking) that lead to biases (systematic errors).
Philosophers such as Schick often discuss error tendencies in terms of fallacies.
Russo discusses decision traps such as plunging in, i.e. reaching a decision before thinking about what it involves.
Your portfolios will involve identification of error tendencies in real life situations.
A good thinking strategy is a pattern of thinking that helps people overcome error tendencies in order to make true judgments and effective decisions.
Possible thinking strategies:
This is harder than it seems (Raiffa anecdote about important decisions).
Cold vs. hot cognition:
Read chapter 1 of each of the 3 textbooks for general introduction.
1. Cognitive: imperfect strategies. Cold cognition.
2. Motivational: self-serving biases, emotions. Hot cognition.
1. Having false beliefs can be good, e.g. baseball?
2. But counterexamples:
a. superstition -> extinction of animals
b. wierd health practices
3. Descriptive (how people think) vs. prescriptive (normative = how people should think).
1. Seeing order when it isn't there. E.g. slot machines. Lottery numbers. Stock market up and down. Leukemia near power lines.
Blue Jays WWWWWWLLLLLLLLL, vs WWLWLLLWLW.
2. Failing to see order when it is there:
e.g. Semmelweiss: childbirth fever
Some cultures don't notice a link between sex and pregnancy. Doctors were slow to notice link between sex and AIDS.
General mechanism: find order in the world. Importance: risk assessment: how dangerous are pesticides, overhead power lines, etc.? Environmentalists versus industry.
Streaks in basketball, exams, gambling. Hockey?
Why do people believe in the hot hand?
Faulty intuitions about chance.
Clustering illusion: e.g. coin flips should alternate between heads and tails.
Other examples: births & full moon, etc.
We have a tendency to overgeneralize from small samples. We often don't understand randomness.
Base causal judments on similarity, e.g. astrology, graphology, physiognomy
homeopathic medicine. Handwriting example.
Professor who is shy, likes to write poetry,
Professor of religion or psychology?
Need to consider baserate information.
Humans are good at pattern matching, not so good at picking up statistical regularities. "makes sense" We look for coherence, even when it isn't there.
Causation is ubiquitous, but it can get in the way of understanding genuinely statistical phenomena
We can take a few instances and plug it into our preconceptions, e.g. racism, sexism.
Statistical inference can be hard, e.g. electromagnetic radiation. Link to melatonin? Jet lag.
Psychological problems result of abuse?
Cancer rates from light cigarettes just as high.
Student has great first year? What to predict for second? Sophomore slump. Sports Illustrated jinx.
Scores are the result of ability + chance
We respond much more to salient examples.
E.g. where is a safe place to vacation?
Buying a car: Consumer Reports versus personal
Clustering illusion (Gilovich, ch. 2)
Tendency to see non-existent patterns in random events.
Representativeness (Gilovich, ch. 2)
Tendency to use assessments of similarity in statistical and causal reasoning.
Spurious causal theories (Gilovich, ch. 2)
Tendency to use unsupported causal theories in place of careful statistical and causal reasoning.
Regression fallacy (Gilovich, ch. 2)
Tendency for people's predictions to ignore that many statistical effects regress to the mean.
Vividness (Russo, ch. 4)
Tendency for information that is particularly salient or emotionally charged to be given undue influence.
Updated Jan. 7, 2003
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