How we know what isn’t so – cognitive factors in false beliefs
description
Transcript of How we know what isn’t so – cognitive factors in false beliefs
![Page 1: How we know what isn’t so – cognitive factors in false beliefs](https://reader035.fdocuments.us/reader035/viewer/2022062519/568151f4550346895dc02c91/html5/thumbnails/1.jpg)
How we know what isn’t so – cognitive factors in false beliefs
Dr. Jeff Saunders
Dept of Psychology
Hong Kong University
![Page 2: How we know what isn’t so – cognitive factors in false beliefs](https://reader035.fdocuments.us/reader035/viewer/2022062519/568151f4550346895dc02c91/html5/thumbnails/2.jpg)
False beliefs
Topic: cognitive factors in false beliefs How we acquire false beliefs?
What cognitive tendencies lead us acquire mistaken beliefs about the world?
Why do false beliefs persist? What tendencies inhibit us from learning from
experience and correcting false beliefs
![Page 3: How we know what isn’t so – cognitive factors in false beliefs](https://reader035.fdocuments.us/reader035/viewer/2022062519/568151f4550346895dc02c91/html5/thumbnails/3.jpg)
Demo: try to outwit the professor in a card guessing game
![Page 4: How we know what isn’t so – cognitive factors in false beliefs](https://reader035.fdocuments.us/reader035/viewer/2022062519/568151f4550346895dc02c91/html5/thumbnails/4.jpg)
Card game strategy?
‘Strategy’: choices were entirely random! But might have perceived that that there
was some causal strategy behind choices No way that opponent could have done
better or worse than chance But might have perceived that there was
some strategy that would have increased the likelihood of winning
![Page 5: How we know what isn’t so – cognitive factors in false beliefs](https://reader035.fdocuments.us/reader035/viewer/2022062519/568151f4550346895dc02c91/html5/thumbnails/5.jpg)
Seeing structure in randomness
One factor in acquiring false beliefs: tendency to see structure in randomness
We are very good at seeing meaningful patterns in the world
Useful and impressive ability! But so pervasive and automatic... can
sometimes lead us astray
![Page 6: How we know what isn’t so – cognitive factors in false beliefs](https://reader035.fdocuments.us/reader035/viewer/2022062519/568151f4550346895dc02c91/html5/thumbnails/6.jpg)
Clustering illusion
Distribution of bombs in London during WWII Was Regent’s Park targeted? No, just random
![Page 7: How we know what isn’t so – cognitive factors in false beliefs](https://reader035.fdocuments.us/reader035/viewer/2022062519/568151f4550346895dc02c91/html5/thumbnails/7.jpg)
Clustering illusion
These are randomly generated points Our minds readily see structure in random
![Page 8: How we know what isn’t so – cognitive factors in false beliefs](https://reader035.fdocuments.us/reader035/viewer/2022062519/568151f4550346895dc02c91/html5/thumbnails/8.jpg)
Home remedy: radishes!
Your friend’s remedy for common cold: eat large amounts of radishes
One day when you are really sick, the friend brings you a bunch of radishes to eat
You think: oh well, might as well try it Next day: you are feeling a lot better! Wow, do radishes really work? Or … could this just be coincidence?
(sounds unlikely to you)
![Page 9: How we know what isn’t so – cognitive factors in false beliefs](https://reader035.fdocuments.us/reader035/viewer/2022062519/568151f4550346895dc02c91/html5/thumbnails/9.jpg)
Health varies over time, semi-randomly, and most illnesses get better on their own
Seek treatment when health at low points Likely to get better regardless of treatment Misinterpretation of spontaneous recovery
could lead to false beliefs about remedies
Spontaneous recovery
![Page 10: How we know what isn’t so – cognitive factors in false beliefs](https://reader035.fdocuments.us/reader035/viewer/2022062519/568151f4550346895dc02c91/html5/thumbnails/10.jpg)
Summary - misperceived causation
We are very good at seeing patterns in the world and generating causal hypotheses
But this tendency can lead us to mistakenly see causal relations in randomness
Clustering illusion Misinterpretation of streaks or clusters that
occur naturally by chance Regression fallacy
Misinterpretation of regression to the mean
![Page 11: How we know what isn’t so – cognitive factors in false beliefs](https://reader035.fdocuments.us/reader035/viewer/2022062519/568151f4550346895dc02c91/html5/thumbnails/11.jpg)
![Page 12: How we know what isn’t so – cognitive factors in false beliefs](https://reader035.fdocuments.us/reader035/viewer/2022062519/568151f4550346895dc02c91/html5/thumbnails/12.jpg)
Why do erroneous beliefs persist?
Suppose we have an false belief Due to clustering, regression, coincidence ...
In principle, exposure to counterevidence might allow one to correct the error
However, some cognitive factors interfere with correction of false beliefs…
![Page 13: How we know what isn’t so – cognitive factors in false beliefs](https://reader035.fdocuments.us/reader035/viewer/2022062519/568151f4550346895dc02c91/html5/thumbnails/13.jpg)
Neglect missing information…
![Page 14: How we know what isn’t so – cognitive factors in false beliefs](https://reader035.fdocuments.us/reader035/viewer/2022062519/568151f4550346895dc02c91/html5/thumbnails/14.jpg)
Example: selection criteria
A manager at a company has unusual method for choosing who to hire
Top 8 candidates compete in chess tournament, winner gets the job
Manager: “Everyone I’ve hired with this method has been excellent!”
![Page 15: How we know what isn’t so – cognitive factors in false beliefs](https://reader035.fdocuments.us/reader035/viewer/2022062519/568151f4550346895dc02c91/html5/thumbnails/15.jpg)
Example: selection criteria
Hiring method: chess tournament If previous employees performed well –
does that mean that hiring method is good? Or are we missing information?
Manager: “Everyone I’ve hired with this method has been excellent!”
![Page 16: How we know what isn’t so – cognitive factors in false beliefs](https://reader035.fdocuments.us/reader035/viewer/2022062519/568151f4550346895dc02c91/html5/thumbnails/16.jpg)
Example: selection criteria
Problem: missing data about how rejected candidates would have performed if hired
Only get feedback about the performance of candidates that were hired
If strong candidate pool, even flawed system would select good performers
Some rejected candidates might have been even better, but no way of knowing
![Page 17: How we know what isn’t so – cognitive factors in false beliefs](https://reader035.fdocuments.us/reader035/viewer/2022062519/568151f4550346895dc02c91/html5/thumbnails/17.jpg)
Home remedy: radishes! (again)
Your friend convinced you that radishes are a good treatment for colds, which is false
Will you learn from experience that radishes do not really help?
Problem: missing information If you belief in treatment, then every time
you are sick you will eat radishes Never get to see how quickly you would
recover without radishes
![Page 18: How we know what isn’t so – cognitive factors in false beliefs](https://reader035.fdocuments.us/reader035/viewer/2022062519/568151f4550346895dc02c91/html5/thumbnails/18.jpg)
Confirmatory evidence more noticeable…
![Page 19: How we know what isn’t so – cognitive factors in false beliefs](https://reader035.fdocuments.us/reader035/viewer/2022062519/568151f4550346895dc02c91/html5/thumbnails/19.jpg)
What evidence is noticed?
Example: belief that your roommate never remembers to wash their dishes
Lots of relevant evidence – every meal at home, either does or does not wash dishes
But which cases will be noticed?
![Page 20: How we know what isn’t so – cognitive factors in false beliefs](https://reader035.fdocuments.us/reader035/viewer/2022062519/568151f4550346895dc02c91/html5/thumbnails/20.jpg)
“Roommate never washes dishes”
Monday Tues
Weds Friday
Sunday
Thurs
Again??!I need a new roommate!
![Page 21: How we know what isn’t so – cognitive factors in false beliefs](https://reader035.fdocuments.us/reader035/viewer/2022062519/568151f4550346895dc02c91/html5/thumbnails/21.jpg)
What evidence is noticed?
Example: belief that your roommate never remembers to wash their dishes
Pos / neg evidence not equally noticeable Salient evidence would only reinforce belief
Unpleasant event, highly salient!
Going smoothly is non-event, not salient
Reinforce belief(even if rare)
![Page 22: How we know what isn’t so – cognitive factors in false beliefs](https://reader035.fdocuments.us/reader035/viewer/2022062519/568151f4550346895dc02c91/html5/thumbnails/22.jpg)
Example: prophecy
Using my psychic powers, I predict: On the first day of Lunar New Year in 2013, … there will be a major earthquake in China
![Page 23: How we know what isn’t so – cognitive factors in false beliefs](https://reader035.fdocuments.us/reader035/viewer/2022062519/568151f4550346895dc02c91/html5/thumbnails/23.jpg)
Example: prophecy
Prophesy: On the first day of Lunar New Year in 2013, major earthquake in China
Specific, falsifiable prediction But - what outcome would you notice?
![Page 24: How we know what isn’t so – cognitive factors in false beliefs](https://reader035.fdocuments.us/reader035/viewer/2022062519/568151f4550346895dc02c91/html5/thumbnails/24.jpg)
Prophesy: On the first day of Lunar New Year in 2013, major earthquake in China
Example: prophecy
WOW! He really is psychic!
Non-event, unlikelyto remember prophesy
Earthquake!New Year
No earthquakeNew Year
![Page 25: How we know what isn’t so – cognitive factors in false beliefs](https://reader035.fdocuments.us/reader035/viewer/2022062519/568151f4550346895dc02c91/html5/thumbnails/25.jpg)
Prophesy: On the first day of Lunar New Year in 2013, major earthquake in China
Example: prophecy
WOW! He really is psychic!
Earthquake!New Year
No earthquakeNew Year
Noticeable outcome would confirm psychic powers, not disconfirm
![Page 26: How we know what isn’t so – cognitive factors in false beliefs](https://reader035.fdocuments.us/reader035/viewer/2022062519/568151f4550346895dc02c91/html5/thumbnails/26.jpg)
http://xkcd.com/628/
![Page 27: How we know what isn’t so – cognitive factors in false beliefs](https://reader035.fdocuments.us/reader035/viewer/2022062519/568151f4550346895dc02c91/html5/thumbnails/27.jpg)
Bias in seeking information…
![Page 28: How we know what isn’t so – cognitive factors in false beliefs](https://reader035.fdocuments.us/reader035/viewer/2022062519/568151f4550346895dc02c91/html5/thumbnails/28.jpg)
Exercise: rule discovery
Goal: to figure out an unknown rule for sequences of three numbers
Some sequences of numbers satisfy the rule, some sequences do not
Here is one sequence of numbers that satisfied the rule: 2-4-6
Now you can suggest numbers for testing I will tell you “yes” or “no”
![Page 29: How we know what isn’t so – cognitive factors in false beliefs](https://reader035.fdocuments.us/reader035/viewer/2022062519/568151f4550346895dc02c91/html5/thumbnails/29.jpg)
Exercise: rule discovery
Demo: test cases to discover rule Initial example chosen so that you would
likely have some guess about the rule Tendency: test additional examples that
would also satisfy rule Problem: did not get opportunity to learn
that your guess was wrong Restricted test cases could only reinforce
mistaken belief about rule
![Page 30: How we know what isn’t so – cognitive factors in false beliefs](https://reader035.fdocuments.us/reader035/viewer/2022062519/568151f4550346895dc02c91/html5/thumbnails/30.jpg)
Application: medical diagnosis
How might confirmation bias lead to misdiagnosis by doctors?
![Page 31: How we know what isn’t so – cognitive factors in false beliefs](https://reader035.fdocuments.us/reader035/viewer/2022062519/568151f4550346895dc02c91/html5/thumbnails/31.jpg)
Example: test for extroversion
Goal: scale for measuring extroversion Items are self-reflective statements
“I often feel that …” “I generally do not …” Each item is rated on scale agree/disagree
1 – ‘strongly agree’ 2 – ‘agree’ 3 – ‘neither agree not disagree’ 4 – ‘disagree’ 5 – ‘strongly disagree’
Exercise: everyone write down a possible item for an extroversion scale
![Page 32: How we know what isn’t so – cognitive factors in false beliefs](https://reader035.fdocuments.us/reader035/viewer/2022062519/568151f4550346895dc02c91/html5/thumbnails/32.jpg)
Example: test for extroversion
In principle, items could test for either presence or absence of extroversion
Presence: “I am often the life of the party” Extroverts would “agree”
Absence: “I often keep to myself at parties” Extroverts would “disagree”
In your sample items, would extroverts be expected to agree or disagree?
Expected result: mostly “agree” items
![Page 33: How we know what isn’t so – cognitive factors in false beliefs](https://reader035.fdocuments.us/reader035/viewer/2022062519/568151f4550346895dc02c91/html5/thumbnails/33.jpg)
Seeking confirmation
Extroversion test example: tended to seek information that confirms not disconfirms Look for presence of a trait not absence Look for +extroversion not -introversion
If asked to make a test for introversion, would have chosen different statements
… even though these are assumed to be opposites along the same continuum
![Page 34: How we know what isn’t so – cognitive factors in false beliefs](https://reader035.fdocuments.us/reader035/viewer/2022062519/568151f4550346895dc02c91/html5/thumbnails/34.jpg)
Wason selection task
Hypothesis: “Cards with an odd number on one side have a circle on the other side”
Which cards need to be flipped to evaluate this hypothesis?
![Page 35: How we know what isn’t so – cognitive factors in false beliefs](https://reader035.fdocuments.us/reader035/viewer/2022062519/568151f4550346895dc02c91/html5/thumbnails/35.jpg)
Wason selection task
To evaluate hypothesis “if odd, then circle” Typical answer: (a) and (c)
Correct answer: (a) and (d)
![Page 36: How we know what isn’t so – cognitive factors in false beliefs](https://reader035.fdocuments.us/reader035/viewer/2022062519/568151f4550346895dc02c91/html5/thumbnails/36.jpg)
Wason selection task
To evaluate hypothesis “if odd, then circle”
Does not matter
If odd, supports hypothesis
If even, does not refute!
If odd, refuteshypothesis
If not circle, would refute hypothesis
![Page 37: How we know what isn’t so – cognitive factors in false beliefs](https://reader035.fdocuments.us/reader035/viewer/2022062519/568151f4550346895dc02c91/html5/thumbnails/37.jpg)
Wason selection task
To evaluate hypothesis “if odd, then circle”
Does not matter
If odd, refuteshypothesis
If not circle, would refute hypothesis
Could only confirm, never refute
![Page 38: How we know what isn’t so – cognitive factors in false beliefs](https://reader035.fdocuments.us/reader035/viewer/2022062519/568151f4550346895dc02c91/html5/thumbnails/38.jpg)
Wason selection task
To evaluate hypothesis “if odd, then circle”
Obviously irrelevant
Incorrectly treated as strong evidence
Relevant but neglected
Obviously relevant
![Page 39: How we know what isn’t so – cognitive factors in false beliefs](https://reader035.fdocuments.us/reader035/viewer/2022062519/568151f4550346895dc02c91/html5/thumbnails/39.jpg)
Wason selection task
Hypothesis: “If drinking beer, then over 18” Which people need to be checked? Logically, exactly same as previous, but
people tend to get this version correct “Permission” schema seems to help
![Page 40: How we know what isn’t so – cognitive factors in false beliefs](https://reader035.fdocuments.us/reader035/viewer/2022062519/568151f4550346895dc02c91/html5/thumbnails/40.jpg)
Wason selection task
Hypothesis: “If odd, then circle” Logically, need to check: odd, square But typically drawn to check circle card,
which could confirm but never disconfirm Confirmation bias in seeking information
![Page 41: How we know what isn’t so – cognitive factors in false beliefs](https://reader035.fdocuments.us/reader035/viewer/2022062519/568151f4550346895dc02c91/html5/thumbnails/41.jpg)
Summary - Confirmation bias
When evaluating a belief, we tend to seek and focus on confirmatory information
As a result, less likely to be exposed to evidence that might refute a false belief
Example demonstrations: Rule discovery exercise Look for stereotypical extroverted traits Wason selection task
![Page 42: How we know what isn’t so – cognitive factors in false beliefs](https://reader035.fdocuments.us/reader035/viewer/2022062519/568151f4550346895dc02c91/html5/thumbnails/42.jpg)
Expectations influence interpretation of evidence…
![Page 43: How we know what isn’t so – cognitive factors in false beliefs](https://reader035.fdocuments.us/reader035/viewer/2022062519/568151f4550346895dc02c91/html5/thumbnails/43.jpg)
Example: knowledge -> perception
By R. C. JamesOnce you know what it is, looks different!
![Page 44: How we know what isn’t so – cognitive factors in false beliefs](https://reader035.fdocuments.us/reader035/viewer/2022062519/568151f4550346895dc02c91/html5/thumbnails/44.jpg)
Bias due to expectations
Bias due to expectations can allow us to interpret highly ambiguous information
Perceptual example: experience allows us to see Dalmatian from degraded image
Adaptive use of knowledge and experience Is there a downside to this? Potential problem: re-enforce false beliefs
![Page 45: How we know what isn’t so – cognitive factors in false beliefs](https://reader035.fdocuments.us/reader035/viewer/2022062519/568151f4550346895dc02c91/html5/thumbnails/45.jpg)
Example: Referees’ judgments
Referees in sports often have to interpret ambiguous information to evaluate penalties
Susceptible to bias from expectations
High tackle or not?
Depends: are you an All-Blacks fan??
![Page 46: How we know what isn’t so – cognitive factors in false beliefs](https://reader035.fdocuments.us/reader035/viewer/2022062519/568151f4550346895dc02c91/html5/thumbnails/46.jpg)
Example: Referees’ judgments
Frank & Gilovich (1988) –effect of black uniforms on referee judgments
Referees evaluated possible penalties from videos
Identical situations except varied uniform color
Finding: more penalties for players wearing black
Explanation: stereotype of black as “bad guy”
![Page 47: How we know what isn’t so – cognitive factors in false beliefs](https://reader035.fdocuments.us/reader035/viewer/2022062519/568151f4550346895dc02c91/html5/thumbnails/47.jpg)
Lack of source memory…
![Page 48: How we know what isn’t so – cognitive factors in false beliefs](https://reader035.fdocuments.us/reader035/viewer/2022062519/568151f4550346895dc02c91/html5/thumbnails/48.jpg)
Trivia quiz
Answer trivia quiz
![Page 49: How we know what isn’t so – cognitive factors in false beliefs](https://reader035.fdocuments.us/reader035/viewer/2022062519/568151f4550346895dc02c91/html5/thumbnails/49.jpg)
Trivia quiz
Compute the number of “true” responses for even numbered statements
Actual: equal true/false Even numbered statements were repeated
from previous trivia quiz (if you took it) Prediction: more “true” for statements that
were repeated
![Page 50: How we know what isn’t so – cognitive factors in false beliefs](https://reader035.fdocuments.us/reader035/viewer/2022062519/568151f4550346895dc02c91/html5/thumbnails/50.jpg)
Illusion of truth effect
False True0.3
0.4
0.5
0.6
0.7
test1
test2Pe
rce
nt j
udg
ed
“tru
e”
Data from my HKU class:
For identical statements, more “true” judgments on second test
Change due to just one prior exposure
![Page 51: How we know what isn’t so – cognitive factors in false beliefs](https://reader035.fdocuments.us/reader035/viewer/2022062519/568151f4550346895dc02c91/html5/thumbnails/51.jpg)
Trivia quiz
Why might there be a bias toward “true”? Repeated statements were more familiar General bias: familiar -> perceived true “Validity effect” or “Illusion of truth effect”
Hasher, Goldstein, & Toppino (1977)
Example of a failure of source memory
![Page 52: How we know what isn’t so – cognitive factors in false beliefs](https://reader035.fdocuments.us/reader035/viewer/2022062519/568151f4550346895dc02c91/html5/thumbnails/52.jpg)
Source memory
Take some fact that you know is true: “The largest ocean in the world is the
Pacific Ocean” How do you know this is true? Can you answer: when and where did you
learn this fact? You know that this fact is true, but you don’t
remember the source of knowledge
Hard!
![Page 53: How we know what isn’t so – cognitive factors in false beliefs](https://reader035.fdocuments.us/reader035/viewer/2022062519/568151f4550346895dc02c91/html5/thumbnails/53.jpg)
Source memory
Human memory is very good at recognition … but memory is not as good for source We know many things… .. but not necessarily how we know
![Page 54: How we know what isn’t so – cognitive factors in false beliefs](https://reader035.fdocuments.us/reader035/viewer/2022062519/568151f4550346895dc02c91/html5/thumbnails/54.jpg)
Source memory
Real life example where poor source memory might lead to persistent false beliefs?
![Page 55: How we know what isn’t so – cognitive factors in false beliefs](https://reader035.fdocuments.us/reader035/viewer/2022062519/568151f4550346895dc02c91/html5/thumbnails/55.jpg)
Urban myths
Lack of source memory can explain persistence of “urban myths”
Suppose we have heard a myth many times Hard to remember whether or not we heard
from a reliable source (Also, we don’t tend to question how we know something – we just do)
So if myth is familiar, tend to believe it Then we might repeat the myth to others,
increasing familiarity for them, and so on ...
![Page 56: How we know what isn’t so – cognitive factors in false beliefs](https://reader035.fdocuments.us/reader035/viewer/2022062519/568151f4550346895dc02c91/html5/thumbnails/56.jpg)
Home remedy: radishes!
I’ve discussed a false remedy: radishes Right now, you remember that this is just a
silly example for illustration But years from now… … may only remember hearing something
about radishes curing the cold Sorry for planting a future false belief!
![Page 57: How we know what isn’t so – cognitive factors in false beliefs](https://reader035.fdocuments.us/reader035/viewer/2022062519/568151f4550346895dc02c91/html5/thumbnails/57.jpg)
![Page 58: How we know what isn’t so – cognitive factors in false beliefs](https://reader035.fdocuments.us/reader035/viewer/2022062519/568151f4550346895dc02c91/html5/thumbnails/58.jpg)
Summary – persistence of false beliefs
Tend to seek confirmatory evidence Neglect missing information Confirmatory evidence more noticeable Biased interpretation of evidence Lack of source memory Effect of these factors: can be very hard to
change a false belief!
![Page 59: How we know what isn’t so – cognitive factors in false beliefs](https://reader035.fdocuments.us/reader035/viewer/2022062519/568151f4550346895dc02c91/html5/thumbnails/59.jpg)
![Page 60: How we know what isn’t so – cognitive factors in false beliefs](https://reader035.fdocuments.us/reader035/viewer/2022062519/568151f4550346895dc02c91/html5/thumbnails/60.jpg)
Avoiding bias?
Try to consider possibility of coincidence We tend to seek causal interpretations, and
neglect the possibility of coincidence Helpful to keep this in mind, and recognize
some specific situations eg. regression to mean
![Page 61: How we know what isn’t so – cognitive factors in false beliefs](https://reader035.fdocuments.us/reader035/viewer/2022062519/568151f4550346895dc02c91/html5/thumbnails/61.jpg)
Avoiding bias?
Be aware of missing information Information required to evaluate a belief is
often unavailable or unnoticeable How well would rejected applicants have performed? If roommate does reliably washes dishes, would I
notice?
Would the condition have improved even without treatment?
Noticing these situations can cue you to be skeptical about beliefs
![Page 62: How we know what isn’t so – cognitive factors in false beliefs](https://reader035.fdocuments.us/reader035/viewer/2022062519/568151f4550346895dc02c91/html5/thumbnails/62.jpg)
Avoiding bias?
Be aware of limited source memory We tend to perceive familiar as true Try to reinforce good information more than
bad information
![Page 63: How we know what isn’t so – cognitive factors in false beliefs](https://reader035.fdocuments.us/reader035/viewer/2022062519/568151f4550346895dc02c91/html5/thumbnails/63.jpg)
Avoiding bias?
Strategy: study science! Thinking like a scientist can help overcome
some of these biases Idea of testing falsifiable predictions Appreciation of randomness and statistics
![Page 64: How we know what isn’t so – cognitive factors in false beliefs](https://reader035.fdocuments.us/reader035/viewer/2022062519/568151f4550346895dc02c91/html5/thumbnails/64.jpg)
Thanks for your attention
![Page 65: How we know what isn’t so – cognitive factors in false beliefs](https://reader035.fdocuments.us/reader035/viewer/2022062519/568151f4550346895dc02c91/html5/thumbnails/65.jpg)