Social Cognition

Mini Review

• The false consensus effect and pluralistic ignorance are wrong guesses about what other people think.
• Both come from using yourself, or other people’s silence, as evidence.

Last Class: The Zipper

• You rated how well you could explain how a zipper works, from 1 to 5. Then you tried to explain it. Then you rated yourself again.
• In the original version of this task, most people rate themselves high, write an explanation that stops after a sentence or two, and then rate themselves lower.

Illusion of Explanatory Depth

• Illusion of explanatory depth: The tendency to believe that one understands how a familiar thing works in more detail than one actually does, which shows up when the person tries to explain it.
• The explanation study (2002): College students rated how well they understood devices such as a zipper, a flush toilet, and a speedometer, then wrote step-by-step explanations, then rated themselves again.
  • Finding: Ratings dropped after writing the explanation, for every device. Seeing their own explanation was what changed the rating.

Why the Illusion Happens

• Knowing how to use something is mistaken for knowing how it works. A person has zipped a jacket thousands of times, and that familiarity is counted as understanding.
• The explanation is never called for. Everyday life asks people to use things, so the gap between using and explaining stays hidden until someone asks for the explanation.
• The same illusion appears for policies and social issues.
• The policy study (2013): People who were asked to explain how a policy would work, step by step, rated their own understanding lower afterward and held their position on the policy less strongly.

Last Class: The Rule

• I said I was thinking of a rule, and that 6, 8, 10 fit it. You proposed your own sets of three, and I said yes or no to each.
• Most of the sets you proposed fit the rule you already had in mind, so each yes felt like progress.
• In reality, a set that breaks your own rule is the only kind that can show your rule is wrong, and almost nobody proposes one until they are stuck.

Confirmation Bias

• Confirmation bias: The tendency to look for, notice, and remember information that fits what a person already believes, and to overlook information that does not.
• The 2-4-6 task (1960): People saw the numbers 2, 4, 6 and tried to discover the rule behind them by proposing their own sets of three and hearing yes or no. The rule was any three numbers that go up.
  • Finding: Most people proposed only sets that fit their first guess, such as 8, 10, 12, and then announced a rule that was wrong. About one in five found the rule on their first announcement.
• Proposing sets that fit your own rule is a reasonable way to test in most everyday situations (1987). What failed in the task was thinking of other rules that also fit 6, 8, 10.

Beyond the Rule Task

• The rule task is a puzzle, and doing well on puzzles like it goes with scores on intelligence tests. Confirmation bias in judging people, evidence, and arguments does not (2008).
• So the effect is broader than failing to test a rule. A belief a person already holds changes three things:
  • what they look for,
  • how they read the evidence they find,
  • and what they remember of it.

Looking for Evidence: The Interview Study

• The interview study (1978): Participants were told to find out whether a person was an extravert, or whether the person was an introvert, and chose interview questions from a list.
  • Finding: Those testing for extraversion chose questions such as “What do you do to liven up a party?” Those testing for introversion chose questions such as “What do you dislike about loud parties?” Either set of questions produces answers that fit the label.
• The answer follows from which question was asked, before the person speaks.

Reading Evidence: The Death Penalty Study

• The death penalty study (1979): Supporters and opponents of the death penalty read the same two studies, one finding that it deters murder and one finding that it does not.
  • Finding: Each side rated the study that agreed with them as well done and the other as flawed. After reading the same two studies, both sides were more sure of their original view than before.
• The same evidence moved the two groups in opposite directions, because each group explained away the half that did not fit.

Reading Evidence, Continued: The Hannah Study

• The Hannah study (1983): Participants were told that a fourth grader named Hannah came from a wealthy family or from a poor one. Half of each group then watched the same video of her taking a test, on which she got some hard questions right and some easy ones wrong.
  • Finding: Without the video, the two groups rated her ability about the same. With the video, those told she was wealthy rated her above grade level, and those told she was poor rated her below it.
• The video was ambiguous, so each group read it as fitting what they had been told, and the belief looked like it came from the evidence.

Why Confirmation Bias Happens

• Looking for a yes is mistaken for testing. A belief can be shown wrong only by evidence against it, and people rarely go looking for that.
• Mental efficiency: We favor information that fits what we already believe because it’s easier to process.
• Self-concept protection: Supporting evidence helps preserve our identity, confidence, and worldview.

Practice: Which Effect Is It?

For each one, say whether it shows the illusion of explanatory depth, confirmation bias, or none of them.

1. A man is sure his phone’s battery drains because of “background apps” until his nephew asks what a background app does.
2. A nurse who thinks a patient is exaggerating pain asks only about what the patient can still do.
3. A woman who believes her neighbor is unfriendly takes his short wave as a brush-off and his long chat as him wanting something from her.
4. A student checks three sources, finds that they disagree, and changes her mind about which one is right.
5. A coach who believes freshmen are unreliable remembers the two who skipped practice and not the six who never missed.

Practice: Answers

1. Illusion of explanatory depth (the understanding was a label, and the question exposed it).
2. Confirmation bias (the questions are chosen to confirm the belief, as in the interview study).
3. Confirmation bias (either behavior is read as fitting the belief, as in the Hannah study).
4. None of them (she looked for disagreement and updated on it).
5. Confirmation bias (the cases that fit the belief are the ones remembered).