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Huanghanming
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need help for calculating an expectation

September 22nd, 2010, 4:48 am

can anyone help me for calculating this expectation? Thanks a lot!where are correlated normal random variables with coefficient c.
Last edited by Huanghanming on September 21st, 2010, 10:00 pm, edited 1 time in total.
 
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DevonFangs
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need help for calculating an expectation

September 22nd, 2010, 5:40 am

It's not so hard.You know the pdf of two correlated r.v., what can you do then?
 
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Antonio
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need help for calculating an expectation

September 22nd, 2010, 6:10 am

 
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Huanghanming
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need help for calculating an expectation

September 22nd, 2010, 6:26 am

I have got it. thanks.
 
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Huanghanming
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need help for calculating an expectation

September 22nd, 2010, 6:29 am

QuoteOriginally posted by: DevonFangsIt's not so hard.You know the pdf of two correlated r.v., what can you do then?but how to calculate the covariance of the lognormal and the normal r.v. ?
 
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DevonFangs
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need help for calculating an expectation

September 22nd, 2010, 7:57 am

Just write down the integral as the very definition of expected value
 
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rg209
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need help for calculating an expectation

September 22nd, 2010, 9:02 pm

How about conditioning wrt to x_1.E(x_1 * exp(x_1+x_2)) = E( x_1* exp x_1 E( exp x_2 / x_1))
 
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Huanghanming
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need help for calculating an expectation

September 23rd, 2010, 6:37 am

you are right. just some tedious calculation... ~>_<~QuoteOriginally posted by: DevonFangsJust write down the integral as the very definition of expected value
 
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Huanghanming
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need help for calculating an expectation

September 23rd, 2010, 6:44 am

the calculation for the conditional expectation is the same tedious as directly applying the bivariate normal density....QuoteOriginally posted by: rg209How about conditioning wrt to x_1.E(x_1 * exp(x_1+x_2)) = E( x_1* exp x_1 E( exp x_2 / x_1))