Let Y Bin(4; p) and assume that the conditional distribution of X given that Y = y is

Poi(y). Write down E(X/Y = y). Use the formula E(X) = E(E(X/Y )) to nd E(X).

Have no idea where tostart...

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- January 21st 2009, 01:05 PMsebjoryConditional Expectation question... No idea what to do
Let Y Bin(4; p) and assume that the conditional distribution of X given that Y = y is

Poi(y). Write down E(X/Y = y). Use the formula E(X) = E(E(X/Y )) to nd E(X).

Have no idea where tostart... - January 22nd 2009, 02:00 PMmr fantastic
- January 22nd 2009, 03:54 PMsebjory
thanks very much for your help.

how ever, i did get to this bit but i found it tough to integrat ethe poisson distribution in this way... i feel im missing something ... - January 22nd 2009, 06:56 PMmr fantastic
- January 23rd 2009, 03:36 AMsebjory
of course the poisson distribution is discrete...(Rofl)

however this is exactly where im having trouble- what exactly does this summation mean and how do use it? - January 23rd 2009, 05:17 AMmr fantastic
- January 23rd 2009, 04:01 PMsebjory
which is 'y' in this case...

therefore E(X) is 4p? - January 24th 2009, 03:03 AMmr fantastic