Example #1 (Bransford & Johnson, Example #1 (Bransford & Johnson, 1973)1973)

““The procedure is quite simple. First, you The procedure is quite simple. First, you arrange things into different groups. Of arrange things into different groups. Of course, one pile may be sufficient, course, one pile may be sufficient, depending on how much there is to do. If depending on how much there is to do. If you have to go somewhere else due to you have to go somewhere else due to lack of facilities, that is the next step; lack of facilities, that is the next step; otherwise you are pretty well set.”otherwise you are pretty well set.”

““washing clothes”washing clothes”

Mental ShortcutsMental Shortcuts

A. SchemasA. Schemas Schemas are cognitive structures Schemas are cognitive structures

representing a person’s knowledge about representing a person’s knowledge about a concepta concept

Schemas:Schemas: help us organize and remember informationhelp us organize and remember information give us expectations for what will happen nextgive us expectations for what will happen next

Priming Stimuli APriming Stimuli A

AdventurousAdventurousSelf-confidentSelf-confidentIndependentIndependentPersistentPersistent

Priming Stimuli BPriming Stimuli B

RecklessRecklessConceitedConceitedAloofAloofStubbornStubborn

Self-Fulfilling ProphecySelf-Fulfilling Prophecy

The process by which one’s expectations The process by which one’s expectations about a person eventually lead that person about a person eventually lead that person to behave in ways that confirm one’s to behave in ways that confirm one’s expectationsexpectations

Rosenthal and Jacobson (1968)Rosenthal and Jacobson (1968)

0

5

10

15

20

25

30

1 2 3 4 5 6

Experimental

Control

Grade in School

IQ Gain

ExampleExample

Snyder, Tanke, & Berscheid (1977)Snyder, Tanke, & Berscheid (1977)

Male participants led to believe they are Male participants led to believe they are speaking with an attractive or unattractive speaking with an attractive or unattractive female.female.

Conversation recorded on two separate tapes.Conversation recorded on two separate tapes. One group of judges listened to the males’ One group of judges listened to the males’

tapes; another group listened to the females’ tapes; another group listened to the females’ tapes.tapes.

DV: judges’ ratings of the males’ and females’ DV: judges’ ratings of the males’ and females’ personalities.personalities.

Snyder et al. (1977) cont.Snyder et al. (1977) cont.Males’ Expectations:

Expected to like “attractive” female more

Males’ Behavior:More outgoing and warm with “attractive” female

Females’ Behavior:More outgoing and warm in “attractive” condition

Mental Shortcuts, cont.Mental Shortcuts, cont.

B. Heuristics:B. Heuristics: cognitive rules of thumb that cognitive rules of thumb that allow people to think in ways that are quick allow people to think in ways that are quick and easy.and easy.

Which of the following are the more Which of the following are the more frequent causes of death in the frequent causes of death in the

United States?United States? 1. Homicide or diabetes? 1. Homicide or diabetes? 2. Flood or infectious hepatitis? 2. Flood or infectious hepatitis? 3. All accidents or strokes?3. All accidents or strokes? 4. All cancers or heart disease?4. All cancers or heart disease? 5. Tornados or asthma?5. Tornados or asthma? 6. Drowning or leukemia?6. Drowning or leukemia? 7. Lightning or appendicitis?7. Lightning or appendicitis? 8. Motor vehicle accident or cancer of the 8. Motor vehicle accident or cancer of the

digestive system?digestive system?

The Availability HeuristicThe Availability Heuristic

Estimating the likelihood of events based Estimating the likelihood of events based on their availability in memory.on their availability in memory.

Problem 1aProblem 1a

In four pages of a novel (about 2,000 words), In four pages of a novel (about 2,000 words), how many words would you expect to find that how many words would you expect to find that have the form _ _ _ _ _ n _ (seven-letter words have the form _ _ _ _ _ n _ (seven-letter words that have “n” as their sixth letter)? Indicate your that have “n” as their sixth letter)? Indicate your best estimate by circling one of the values best estimate by circling one of the values below:below:

0 1-2 3-4 5-7 8-10 11-15 16+0 1-2 3-4 5-7 8-10 11-15 16+

Problem 1bProblem 1b

In four pages of a novel (about 2,000 words), In four pages of a novel (about 2,000 words), how many words would you expect to find that how many words would you expect to find that have the form _ _ _ _ ing (seven-letter words have the form _ _ _ _ ing (seven-letter words that end with “ing”)? Indicate your best estimate that end with “ing”)? Indicate your best estimate by circling one of the values below:by circling one of the values below:

0 1-2 3-4 5-7 8-10 11-15 16+0 1-2 3-4 5-7 8-10 11-15 16+

Problem 2Problem 2 Linda is 31 years old, single, outspoken, and very bright. Linda is 31 years old, single, outspoken, and very bright.

She majored in philosophy. As a student, she was She majored in philosophy. As a student, she was deeply concerned with issues of discrimination and deeply concerned with issues of discrimination and social justice, and also participated in anti-nuclear social justice, and also participated in anti-nuclear demonstrations.demonstrations.

Rank order the following in terms of their probability that Rank order the following in terms of their probability that they are true.they are true.

_Linda is a teacher in elementary school_Linda is a teacher in elementary school_Linda works in a bookstore and takes yoga classes_Linda works in a bookstore and takes yoga classes_Linda is active in the feminist movement_Linda is active in the feminist movement_Linda is a bank teller_Linda is a bank teller_Linda is an insurance salesman_Linda is an insurance salesman_Linda is a bank teller and is active in the feminist _Linda is a bank teller and is active in the feminist

movementmovement

The Representativeness HeuristicThe Representativeness Heuristic

Judging the likelihood of things in terms of Judging the likelihood of things in terms of how well they seem to match a prototypehow well they seem to match a prototype

John P. was a quiet, mild-mannered high John P. was a quiet, mild-mannered high school student who was suspended from school student who was suspended from school six years ago when he was school six years ago when he was convicted of selling drugs to an convicted of selling drugs to an undercover agent. He received a undercover agent. He received a suspended sentence and was placed on suspended sentence and was placed on three year’s probation. Since that time he three year’s probation. Since that time he has drifted from job to job, never exhibiting has drifted from job to job, never exhibiting much interest of initiative. John is much interest of initiative. John is presently under police investigation again. presently under police investigation again.

John P. John P.

Please rank the following statements by the Please rank the following statements by the probability that they will be among the results of probability that they will be among the results of the investigation. Use 1 for the most probable the investigation. Use 1 for the most probable statement, 2 for the second, etc.statement, 2 for the second, etc.

_John killed his employer_John killed his employer

_John is a petty thief_John is a petty thief

_John is a child molester_John is a child molester

_John is involved in interstate transportation of _John is involved in interstate transportation of stolen carsstolen cars

Please rank the following statements by the Please rank the following statements by the probability that they will be among the results of probability that they will be among the results of the investigation. Use 1 for the most probable the investigation. Use 1 for the most probable statement, 2 for the second, etc.statement, 2 for the second, etc.

_John killed his employer to keep him from telling _John killed his employer to keep him from telling the police about John’s drug-dealingthe police about John’s drug-dealing

_John is a petty thief_John is a petty thief_John is a child molester_John is a child molester_John is involved in interstate transportation of _John is involved in interstate transportation of

stolen carsstolen cars

A newly hired engineer for a medical laser A newly hired engineer for a medical laser firm in San Diego had four years of firm in San Diego had four years of experience in excimer lasers and excellent experience in excimer lasers and excellent qualifications. When asked to estimate the qualifications. When asked to estimate the starting salary for this employee, my starting salary for this employee, my administrative assistant (knowing very little administrative assistant (knowing very little about the profession or the industry) about the profession or the industry) guessed an annual salary—excluding guessed an annual salary—excluding benefits—of $45,000. What is your benefits—of $45,000. What is your estimate?estimate?

A newly hired engineer for a medical laser A newly hired engineer for a medical laser firm in San Diego had four years of firm in San Diego had four years of experience in excimer lasers and excellent experience in excimer lasers and excellent qualifications. When asked to estimate the qualifications. When asked to estimate the starting salary for this employee, my starting salary for this employee, my administrative assistant (knowing very little administrative assistant (knowing very little about the profession or the industry) about the profession or the industry) guessed an annual salary—excluding guessed an annual salary—excluding benefits—of $145,000. What is your benefits—of $145,000. What is your estimate?estimate?

The Anchoring HeuristicThe Anchoring Heuristic

When making a prediction, people When making a prediction, people sometimes start with a beginning sometimes start with a beginning reference point (or anchor) and then adjust reference point (or anchor) and then adjust it to reach a final decision.it to reach a final decision.

Problem: they adjust insufficiently.Problem: they adjust insufficiently.

This helps explain:This helps explain: FAEFAE False ConsensusFalse Consensus