Probability vs. Frequency

The Political Poll Problem (307)

Here are the results of two opinion polls that compared the popularity of two political candidates.  Candidate A had appeared in 6 polls and won 5 of them.  Candidate B, on the other hand, had appeared in 18 polls and won 9 of them.  Now, for the first time, Candidates A and B will be tested against each other in the same poll.  Which candidate do you expect to win?

Simulation Heuristic:

Involves the construction of a mental model of a situation and then "running the model" to predict the course of events.

The Airport Drive Problem (305)

Mr. Crane and Mr. Tees were scheduled to leave the airport on different flights at the same time.  They traveled from town in the same limousine, were caught in a traffic jam, and arrived at the airport 30 minutes after the scheduled departure time of their flights.  Mr. Crane is told that his flight left on time.  Mr. Tees is told that his flight was delayed and just left five minutes ago.  Who is more upset, Mr. Crane or Mr. Tees?

Availability Heuristic:

If relevant examples can readily be retrieved from memory, then the class of events must occur with a high probability.

List of names:

George Clooney

Megan Archibald

Frank Sinatra

Bill Clinton

Nicole Harris

Michael Jordan

Brenda Lopez

Alice Thompson

Betty Hastings

Oskar Schindler

Holly Iverson

David Letterman

Hannah Jackson

Stephen Colbert

Patricia Hansen

Jennifer Douglas

Tracy Johnson

Karl Malone

John Glenn

Benjamin Franklin

Ursula Nelson

Bruce Wayne

Lucy Peterson

Eva Jones

Brad Pitt

Angela Frederick

Harry Potter

Nancy England

Charlton Hesston

Clint Eastwood

Brigham Young

Lindsey Watters

Abigail Evers

Garth Brooks

Richard Simmons

Veronica Webb

Tom Cruise

Deborah Ames

Ruth Bridgewater

Calvin Klein

List as many as you can from memory (may omit for time).

Were there more men's names or more women's names in the list?

Representativeness Heuristic:

If I flip a coin six times, am I more likely to get HTTHTH or HHHHHH?

Events that are representative or typical of a class are assigned a high probability of occurrence.

Emotion Vs. Logic in Decision Making

Two processes describe decision making:

System 1:  Emotional

System 2:  Logical

In making predictions and judgments under uncertainty, people do not appear to follow the calculus of chance or the statistical theory of prediction.  Instead, they rely on a limited number of heuristics which sometimes yield reasonable judgments and sometimes lead to severe and systematic errors.  (301-302)

Four Heuristics:

Representativeness Heuristic

Availability Heuristic

Simulation Heuristic

Probability vs. Frequency Heuristic

Most illogical.

Humans make illogical decisions.