Expected value of binomial distribution with uniform parameter

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Greekguy
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Hello and I would like to thank you for your space in this website

I'm from Greece and i have exams in next days

I need some help with an exercise that I can not solve!

There is a probability density function with the following type :

P(Y=y/X=x)=f(y,x)= $${n \choose y}* {x}^{y} * ({1-x})^{n-y}=\begin{cases} \\ \end{cases}$$ (i don't know how to delete the last two symbols the "=" and the "{")
y=0,1,2,,,n

fxX=1 for 0<=x<=1 and fxX=0 in other space. Find E(Y)I wish that there is someone who could help me with this mountain!

Thank you !
 
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Hi, Greekguy! (Wave)

It's not clear what $f_x$ represents, because it does not relate to the conditional probability density $f(y,x)$. Could you be more explicit?
 
Euge said:
Hi, Greekguy! (Wave)

It's not clear what $f_x$ represents, because it does not relate to the conditional probability density $f(y,x)$. Could you be more explicit?
Thank you so much with your time! i exprees the exercise with a photo and if you can, help me :)View attachment 6370
 
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  • Screenshot of a Greek-language exercise sheet: Theme 3 gives the conditional pmf P(Y=y | X=x) = C(v,y) x^y (1-x)^(v-y) for y = 0, 1, 2, ..., v, with f_X(x) = 1 for 0 ≤ x ≤ 1, and asks for E(Y); Theme 4 gives a joint density f(x,y) = x - y for 0 < x, y < 1, and 0 otherwise.
    ασκηση2.png
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