Focal Points
(Schelling’s Points)
Thomas C. Schelling
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Born in 1921
Ph.D. in Economics, Harvard University
Currently – University of Maryland school of public
affairs.
Worked in Economics / political sciences.
8 books more then 140 papers:
1.
2.
3.
The Strategy of Conflict, 1960
Arms and Influence, 1976
Bargaining, Communication and Limited War, 1993
“The Strategy of Conflict”
Deals with Theory of Bargaining/conflict/strategy.
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1.
2.
3.
4.
Elements of A Theory of Strategy.
A Reorientation of Game Theory,
Strategy with a Random Ingredient.
Surprise Attack: A Study of Mutual Distrust.
We are talking about a very interesting concept that resides
inside 15 pages from the first chapter of the book.
‫להוציא עפרונות‬
Solutions
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Question 1:
36/42 wrote HEADS, 6/42 wrote TAILS.
Question 2:
37/41 picked one of the FIRST THREE
NUMBERS (7, 100, 13) with 7 leading on a
slight margin, 100 second place and 13 third
place.
Solutions
Question 3:
24/41picked upper left corner. 38/31 were on
that same diagonal.
 Question 4:
Absolute majority picked “Grand Central
Station” (information booth).
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Solutions
Question 5:
All of them picked 12:00 noon.
 Question 6 :
Variety of answer, but 2/5 picked 1.
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Solutions
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Question 7:
12/41 picked 1,000,000$. 38/41 picked power
of 10 number (the three others were 2 * 64$
and 1 * 64,000$).
Question 8:
36/41 split it fifty-fifty.
Focal Point
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“People can often coordinate their intentions
with others if each knows that the other is
trying to do the same.”
“A Prime characteristic of most of these
‘solutions’ …., is some kind of prominence…”
This prominence depends on time and place
and who the people are.
What has been done
Theoretical Work:
 Gauthier (1975) “coordination”.
 Bacharach (1993) “Variable Universe
Games”
 Janssen (1995) “Rationalizing Focal Points”
 Sugden (1995) “Toward a Theory of Focal
Points”
What has been done
Experimental Work:
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Van Huyck (1990) “Tactic Coordination Games”.
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Mehta, Starmer, Sugden:
(1992) “an experimental investigation of focal
points in coordination and bargaining”.
(1994) “the nature of salience, empirical
investigation of pure coordination games”
(1994) “focal points in pure coordination games,
an experimental investigation”
What has been done
Overview Papers:
 Janssen (1998) “Focal Points”.
Computer Science Papers:
 Sarit Kraus, Jeff Rosenschein, Maier Fenster (2000)
“Exploiting Focal Points Among Alternative
Solutions: Two Approaches”
Conference:
 Focal Points – coordination, complexity and
communication in strategic contexts (Lund
University, august 1997).
Our Path
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Goal:
Using Focal Points insights in the problem of
selection between multiple equilibriums with same
utility.
Example: 1)Robot finding a key.
2)Travel-Agent agent.
Any application that a computer agent needs to select
between options for a human agent.
The 1st Sub Goal:
Improving Machine Learning classifiers using
Focal Points.
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The Domain:
A game were the user has to choose a goal
between few goals with the same payoff.
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Using the following FP properties:
1.
Uniqueness
2.
Centrality
3.
Firstness
The Method:
1.
Data Gathering
2.
Building ANN/ID3 tree classifiers (given a
game instance will classify which goal
the user will choose).
3.
Incorporate Focal Point properties into
the data and hope for better classification
with shorter learning time.
Discussion