Google Answers Logo
View Question
 
Q: game theory ( No Answer,   5 Comments )
Question  
Subject: game theory
Category: Business and Money > Economics
Asked by: vitaminc-ga
List Price: $2.00
Posted: 05 Nov 2002 19:31 PST
Expires: 05 Dec 2002 19:31 PST
Question ID: 100008
Construct a two player extensive form game with perfect information
that has a subgame perfect equilibrium in (weakly) dominated
strategies.

Request for Question Clarification by rbnn-ga on 09 Nov 2002 17:06 PST
There are several different definitions of "weakly dominated" in the
literature. Can you specify the definition of "weakly dominated" that
you are using with respect to this question?

Also, I am interpreting "equilibrium in weakly dominated strategies"
to mean an equilibrium each constituent strategy of which is weakly
dominated by some other strategy; if there is a specific definition
for this term as well that you are using, please delineate it.

Clarification of Question by vitaminc-ga on 10 Nov 2002 13:14 PST
Fr example:
            Bob
         L       R
Alice T 10,10   0,0
      B 10,10   1,0

A pure strategy s weakly dominate a pure strategy s' for Alice, if
payoff A(s,t)>=payoff A(s',t) for all strategies t for Bob.  And
payoff A(s,t)>payoff A(s',t) for some t.

Clarification of Question by vitaminc-ga on 13 Nov 2002 16:38 PST
The tree has 5 nodes(from 0 to 4). 
The root is 0.(player 1)
 
The player 1 moves from the root are as follows: 

There is an edge labeeled l from 0 to 1.
There is an edge labelled r from 0 to 2. 

The player 2 moves are as follows: 

There is an edge labelled L from 2 to 3 
There is an edge labelled R from 2 to 4 

The payoffs for:
Node 1 is (a1,b1)
Node 3 is (a2,b2)
Node 4 is (a3,b3)

Remark: Don't mix up dominateED and dominANT strategies.
Suppose a3>a1=a2=b1=b2=b3, then the subgame perfect equilibrium(l,L)
is in dominated strategies.

Clarification of Question by vitaminc-ga on 13 Nov 2002 16:40 PST
Above is the solution.
Answer  
There is no answer at this time.

Comments  
Subject: Re: game theory
From: rbnn-ga on 10 Nov 2002 22:55 PST
 
Although I do not have a formal proof, it would surprise me if there
existed a finite game with perfect information with a Nash equilibrium
 comprising strategies each of which themselves were weakly dominated.
Subject: Re: game theory
From: vitaminc-ga on 11 Nov 2002 13:23 PST
 
i think i got it. Thanks anyway ^__^
Subject: Re: game theory
From: rbnn-ga on 11 Nov 2002 16:46 PST
 
Can you post briefly the solution then? I am really curious :-)
Subject: Re: game theory
From: rbnn-ga on 13 Nov 2002 17:07 PST
 
Thank you very much for posting the solution. I don't know why I
wasn't able to figure this out myself though - sorry!
Subject: Re: game theory
From: vitaminc-ga on 13 Nov 2002 19:07 PST
 
That's ok.
You did a great job for helping other questions.
Thanks again.
^^

Important Disclaimer: Answers and comments provided on Google Answers are general information, and are not intended to substitute for informed professional medical, psychiatric, psychological, tax, legal, investment, accounting, or other professional advice. Google does not endorse, and expressly disclaims liability for any product, manufacturer, distributor, service or service provider mentioned or any opinion expressed in answers or comments. Please read carefully the Google Answers Terms of Service.

If you feel that you have found inappropriate content, please let us know by emailing us at answers-support@google.com with the question ID listed above. Thank you.
Search Google Answers for
Google Answers  


Google Home - Answers FAQ - Terms of Service - Privacy Policy