Expected cutoff for dse ??

[Akshay Jain]

i also marked the same....

[madhur1987]

@B what ans did you mark for that set of voting questions?

[B]

You yourself said: "However, since the mailman delivers a female one first no matter what", then how is MF a case? MF means a male one is being delivered first.

[B]

i remember for the third one i marked either a or b. for the second one i had marked the one with the payoffs: (4,0,5). if these twoare right then the first one would be right too

[madhur1987]

even i have marked these options 2nd one is surely correct purposal of persons 1. but not sure of 1 and 3 rd one. marked same options as you said

[B]

I checked them taking a lot of time. Shouldn't be wrong :|. I dont remember what I had marked for the first one though. Shayad first ya second option mark kiya tha..

[shanks]

@B correct me...i thought the letters can arrive at post office in 4 ways.   MM, MF, FM, FF.
now whatever the order the letters may come in the postoffice..the  postman will deliever female first.
Thus female first are 3 cases. FF,FM, MF (though male comes to the post office first the female one is delivered).

therefore prob, is 1/3

[madhur1987]

@ b i am getting 5 0 4 for 2nd since purposal of player1 is asked so player 1 try to maximise his utility and giving more than 3 to any other player so that he can total 2 yes and his purposal will be accepted.

[B]

@madhur- the question was that 2 letters arrive out of which the first one is delivered to female and what is the probability that the Second one is delivered to the female too. The cases then amount to FM and FF. MF can't be a case because the first letter will always be delivered to a female.

also see 2nd will try to choose (0,5,4). Given that he will choose this, the first player will try to choose (4,0,5)because the third player will be getting a payoff of 4 in both the situations if the first player chooses (5,0,4) and it was mentioned in the question that if a voter is getting the same payoffs as any other proposal he will reject the proposal. So he will reject first voter's proposal. The ideal proposal for the first voter was asked after the second voter's. So i took this into account. I maybe wrong in this :|

[B]

And i forgot to add, if both the 2nd and 3rd voters reject his proposal, (mainly because the 2nd one will get a 0 and the third one knows that 4 is the payoff that he'll get from the 2nd one's proposal too) then 1st voter will either get a 0 or a 3. So it makes sense for him to keep a 4 and give a 5 to the 3rd voter to make him accept his proposal.

[Sinistral]

EDITed
My take: the answer to letters wala question should be  1/2 .

[B]

@ Sinistral- Thanks man!

[SRV]

For All those who think the answer is 1/2.

DSE 2009 question.

18. You've been told that a family has two children and one of these is
a daughter. What is the probability that the other child is also a daughter?
a) 1/2
b) 1/3
c) 1/4
d) 3/4
Why is the answer 1/3 here?

[B]

@ SRV: The question in 2009 was, one of these is a daughter, not the first one is a daughter. However, the question this year was, first letter delivered to a female. Big difference.

[Sinistral]

Support: DS,SD,DD
Pr(DD)=1/3

D: Daughter
S: Son

[Ameya]

there are two types of questions..the one you mention does not have order. it says one is daughter so the possibilities are DD, DS, SD out of which the probability is 1/3
However in the letter question,
you work at a newspaper company, you recieve two letters everyday. the postman has a ladies first policy, provided there is a letter from a female. the postman has delivered the first letter for the day and it is from a female. what is the probability that the second is also from a female.
The difference in this question is order is given. we know that the 'first' letter is from a female. the second, therefore, can be from a male or a female. only two possibilities. hence, 1/2

[B]

@ Sinistral- here too if the first one is a daughter, don't the cases reduce down to 2 instead of 3?

[Sinistral]

EDIT:

Deleted

[Sinistral]

yes

[SRV]

Oh yes!