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fmfreshman
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Joined: October 4th, 2012, 8:09 pm

Probality problem

April 19th, 2013, 8:13 am

Suppose random variable X converges to Y in L2 spaceHow can we prove the expectation E(e^X-e^Y) converges to zero, any ideas?
 
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deimanteR
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Joined: February 5th, 2013, 11:26 am

Probality problem

April 19th, 2013, 2:30 pm

This does not follow. You need extra conditions and can try using the dominated convergence or maybe the sequence is uniformly integrable?
 
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EscapeArtist999
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Joined: May 20th, 2009, 2:49 pm

Probality problem

April 29th, 2013, 2:00 pm

QuoteOriginally posted by: deimanteRThis does not follow. You need extra conditions and can try using the dominated convergence or maybe the sequence is uniformly integrable?I think if lim_(n -> infty) E[exp(2*max(X_n,Y))] < infty you can use the mean value theorem and cauchy shwartz (in addition to L2) to get convergence... this is b=very simplistic... sure there s a better soln - but a first stab.