heuristics g2

R.SalimiN.Mohammadi

CONTENT

Introduction

Heuristic Types

Gaze heuristic

Recognition heuristic

Social heuristic

Heuristics Based on Reasons

Take the best heuristic

Tallying heuristic

Hindsight bias

Conclusion

Introduaction

WHAT to DO

?

What is Unbounded Rationality ?

Unbounded Rationality

infinite amount of time

all relevant informationIn models of Bounded

Rationality(Simon’s term):

how do humans who have little time & knowledge

behave?

3 Programs associated with bounded rationality

1

• The study of optimization under constraints.

2• The study of cognitive illusion.

3

•The study of fast & frugal heuristic.

Heuristic is a rule:

A rule is not necessarily a heuristic, unless it embodies 3 qualities

Heuristics Versus Rules

1-Heuristics exploit evolved capacities

2-Heuristics exploit structures of environments

3- heuristics are distinct from “as if” optimization models

Simon’s vision of bounded rationality

Simon: Human rational behavior is

structure of

task

environment

capabilities of the actor

Heuristic Types

Gaze Heuristic

Gaze heuristicPRABOBOLAInitial DistanceInitial VelocityProjection AngleProjection SpeedDirection of The Wind

No such robots exist yet!

RUNNING SPEED

ANGLE OF GAZE REMAINS CONSTANT

NOT COMPUTE THE POINT AT WHICH THE BALL WILL LAND, BUT HE WILL BE THERE

Gaze heuristic

FAST and FRUGAL A REAL EXPERINCE . . .

Heuristic Type

Recognition Heuristics

TWO CITIES IN

UNITED STATES

San DiegoSan Antonio

GERMAN

Which city has

more inhabitant?

33 %

66 %

SAN ANTONIO

SAN DIEGO 100 %

0 %

Recognition heuristic

AMERICANWHAT

HAPPENED …!?

Less Knowledge

More Correct Inference

Ecological Rationality:

Correlation between recognition & criteria

Recognition validity:

α = R / ( R + W )

recognition information

further knowledge

less-is-more effect

Less-is-more in groups

Decision to go to museum

which museum?

The less-is-more effect

)1(

)1(

2

1

)1(

)1)((

)1(

)(2

NN

nn

NN

nNnN

NN

nNnc

N: number of objects

n: number of recognized objects

α: recognition validity

β: knowledge validity

The recognition heuristic will yield aless-is-more effect if α > β

Heuristic Type

Social Heuristics

“Do what the majority do” heuristic

Darwin

Decision to marry

Single or married

Ecological Rationality of

do-what-the-majority do Heuristics

Similarenvironments

Stableenvironments

Noisy

environments

Heuristic Type

Heuristics Based on Reasons

Heuristic Type

Take the Best &Tallying

Take The Best heuristic (TTB)

ONE-REASON DECISION MAKINGSEARCH BY VALIDITY

Validities Cues School A School B

0.9 reputation + -

0.6 distance - +

0.8 students - +

ONE-REASON STOPPING RULE

Validities Cues School A School B

0.9 reputation + -

0.6 distance - +

0.8 students - +

Random

search

Stop after

searching m

cues

Tallying rull

Tallying heuristic

Ecological Rationality of Take The Best and Tallying

Take The BestNoncompensatory

Tallying Compensatory

Hindsight Bias

Hindsight Bias

Which has more cholesterol , cake or pie?

Cues Original Feedback Recall

Saturated fat (80%) cake? Pie "cake" cake> pie

Calories (70%) cake> pie

Protein (60%)

Choice cake cake

Confidence 70% 80%

Which heuristic to use?

Using heuristic unconsciously

adapt heuristics to changing environment with

feedback.

Evaluating creditworthy

How people adapt their heuristics to

the structure of environment

Robustness

• the ability to make predictions about the future or new events

fitness

• the ability to fit the past or already known data

Simplicity can lead to higher predictive

accuracy

The building Blocks of Heuristics

Heuristics In Hospital

CONCLUSION

CONCLUSION