Social Choice Theory
3.2 Sen on Liberalism
Johns Hopkins University, Spring 2014
Majority Rule leads to the voting paradox. But there is another diculty
with this collective choice rule: it is illiberal.
Sen: Given other things in the society, if you pref
Game Theory
2.1 Zero Sum Games
Johns Hopkins University, Spring 2014
Osborne and Rubinstein: Game theory is a bag of analytical tools
designed to help us understand the phenomena that we observe when
decision-makers interact. The basic assumptions that un
Game Theory
2.2 Nonzero Sum Games
Johns Hopkins University, Spring 2014
Things are no longer so clean once we move on to nonzero sum games.
The equilibria of these games often lack the nice properties of equilibria
of strictly competitive games.
Ex. Stag
Game Theory
2.3 Extensive Games
Johns Hopkins University, Spring 2014
Interactive choice situations often have a sequential structure. This
structure is made explicit in extensive games.
An extensive game has perfect information if each player, when makin
Exercise Set 4
AS.150.330: Decisions, Games, and Social Choice
Johns Hopkins University, Spring 2014
Hard copy due in class on Mar 27. [92 points total]
4.1 Consider the following interactive choice situation:
Ex. Discrete Guess
2
3
of the Average.
Three
Game Theory
2.4 Cooperative Games
Johns Hopkins University, Spring 2014
In a noncooperative game, each player acts alone and the outcome
depends on their individual actions.
In a cooperative or coalition game, the outcome depends on the joint
action of a
Game Theory
2.5 Application I: Morality
Johns Hopkins University, Spring 2014
Gauthier [1991]
Morality faces a foundational crisis. Contractarianism oers the only
plausible resolution of this crisis. These two propositions state my theme.
What follows is
Game Theory
2.6 Application II: Convention
Johns Hopkins University, Spring 2014
Lewis Convention [1969]
It is often said that language is conventional. But what does this mean
exactly? It is not the case that all of our linguistic conventions could have
Social Choice Theory
3.1 Arrows Theorem
Johns Hopkins University, Spring 2014
Suppose that a heterogeneous group of individuals, or citizens, must
choose between two or more group actions or policies. Each citizen has
their own preferences over the set of
Exercise Set 6
AS.150.330: Decisions, Games, and Social Choice
Johns Hopkins University, Spring 2014
Hard copy due on May 9. [53 points total]
6.1 Suppose that the following holds in society:
The utility of exploiting another is 1
The utility of coopera
Decision Theory
1.3 Decisions Under Risk
Johns Hopkins University, Spring 2014
What should you do in a choice situation where you can assign
probabilities to the outcomes of each of your potential actions?
Ex. Pharmaceutical Company.
You are the CEO of a
Decision Theory
1.4 Paradoxes and Problems
Johns Hopkins University, Spring 2014
When making a decision under risk, why maximize expected utility?
Answer. In the long run, you will be better o by maximizing EU.
Reply. No real-life decision maker will ever
Decision Theory
1.5 Causal vs. Evidential Decision Theory
Johns Hopkins University, Spring 2014
Ex. Newcombs Paradox.
You are standing in front of a table on top of which are two boxes A and
B. Box A is transparent and you can see that it contains $1000.
Decision Theory
1.6 Risk-Weighted Expected Utility
Johns Hopkins University, Spring 2014
How to capture an agents attitudes towards risk in decision theory?
Ex. Elvis Stamp & Gloves.
You are a stamp collector who lives in a cold climate. Two fair coins ar
Some Counterexamples
to Causal Decision Theory
Andy Egan
Australian National University/University of Michigan
Many philosophers have been converted to causal decision theory by
something like the following line of argument: Evidential decision
theory end
Exercise Set 2
AS.150.330: Decisions, Games, and Social Choice
Johns Hopkins University, Spring 2014
Hard copy due in class on Feb 27. [66 points total]
2.1 Consider the following choice situation:
Ex. Space Station.
You are conducting important experimen
Exercise Set 3
AS.150.330: Decisions, Games, and Social Choice
Johns Hopkins University, Spring 2014
Hard copy due in class on Mar 13. [28 points total]
3.1 Recall the following medical Newcomb case:
Ex. Smoking.
Suppose that smoking is strongly correlate
The decision matrix
Table 2.6
_
You survive You die
_-
Take rst: bet $100 $0
Take second bet $0 $100
_-
as a result you will have to undergo a risky and life-threatening operation.
a choice between a
For some reason, never mind why, you are offered
bet
Decision Theory
1.2 Decisions Under Ignorance
Johns Hopkins University, Spring 2014
What should you do in a choice situation where you do not know the
probabilities of the outcomes of one or more of your potential actions?
fresh
spoiled
eat raw
5
-10
eat
Decision Theory
1.1 Setup
Johns Hopkins University, Spring 2014
Faced with a real-world or hypothetical choice situation, the rst task of
a decision theorist is to set out precisely the relevant actions of the
decision maker, the relevant states of the wo
Decisions, Games, and Social Choice
Johns Hopkins University, Spring 2014
Instructor
Oce Hours
Justin Bledin
Assistant Professor
Philosophy Department
Gilman 206
jbledin@jhu.edu
Tu 3:15pm-4:15pm & by appt
Teaching Assistant
Oce Hours
Tom Wilk
Ph.D. Studen
Exercise Set 1
AS.150.330: Decisions, Games, and Social Choice
Johns Hopkins University, Spring 2014
Hard copy due in class on Feb 13. [68 points total]
1.1 Consider the following choice situation:
Ex. Vacation.
You have a few days of vacation coming up a