$L^p$ integrability question
$begingroup$
The question is simply: If I have two random variables $X,Y in bigcap_{pgeq 1} L^p(Omega)$ and a third $Z$ r.v. such that
$$XZ=Y$$
can I conclude that $Zin bigcap_{pgeq 1}L^p(Omega)$?
(I know this would't hold for a single $L^p(Omega)$ space, the point is that both $X$ and $Y$ are in all $L^p(Omega)$, $pgeq 1$)
Or, in other words, if $Xneq 0$, $Xin bigcap_{pgeq 1} L^p(Omega)$ is then $1/X in bigcap_{pgeq 1} L^p(Omega)$?
Thank you very much for the help!
real-analysis probability-theory measure-theory random-variables lp-spaces
$endgroup$
add a comment |
$begingroup$
The question is simply: If I have two random variables $X,Y in bigcap_{pgeq 1} L^p(Omega)$ and a third $Z$ r.v. such that
$$XZ=Y$$
can I conclude that $Zin bigcap_{pgeq 1}L^p(Omega)$?
(I know this would't hold for a single $L^p(Omega)$ space, the point is that both $X$ and $Y$ are in all $L^p(Omega)$, $pgeq 1$)
Or, in other words, if $Xneq 0$, $Xin bigcap_{pgeq 1} L^p(Omega)$ is then $1/X in bigcap_{pgeq 1} L^p(Omega)$?
Thank you very much for the help!
real-analysis probability-theory measure-theory random-variables lp-spaces
$endgroup$
add a comment |
$begingroup$
The question is simply: If I have two random variables $X,Y in bigcap_{pgeq 1} L^p(Omega)$ and a third $Z$ r.v. such that
$$XZ=Y$$
can I conclude that $Zin bigcap_{pgeq 1}L^p(Omega)$?
(I know this would't hold for a single $L^p(Omega)$ space, the point is that both $X$ and $Y$ are in all $L^p(Omega)$, $pgeq 1$)
Or, in other words, if $Xneq 0$, $Xin bigcap_{pgeq 1} L^p(Omega)$ is then $1/X in bigcap_{pgeq 1} L^p(Omega)$?
Thank you very much for the help!
real-analysis probability-theory measure-theory random-variables lp-spaces
$endgroup$
The question is simply: If I have two random variables $X,Y in bigcap_{pgeq 1} L^p(Omega)$ and a third $Z$ r.v. such that
$$XZ=Y$$
can I conclude that $Zin bigcap_{pgeq 1}L^p(Omega)$?
(I know this would't hold for a single $L^p(Omega)$ space, the point is that both $X$ and $Y$ are in all $L^p(Omega)$, $pgeq 1$)
Or, in other words, if $Xneq 0$, $Xin bigcap_{pgeq 1} L^p(Omega)$ is then $1/X in bigcap_{pgeq 1} L^p(Omega)$?
Thank you very much for the help!
real-analysis probability-theory measure-theory random-variables lp-spaces
real-analysis probability-theory measure-theory random-variables lp-spaces
edited Dec 7 '18 at 13:47
Davide Giraudo
126k16150261
126k16150261
asked Aug 15 '13 at 13:29
MarkMark
82
82
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1 Answer
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$begingroup$
Take $Omega:=(0,1)$ with Lebesgue measure and $X(omega):=omega$. $X$ is bounded, hence in all the $L^p$ (as $Omega$ has finite measure) but its reciprocal is not even integrable.
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$begingroup$
Take $Omega:=(0,1)$ with Lebesgue measure and $X(omega):=omega$. $X$ is bounded, hence in all the $L^p$ (as $Omega$ has finite measure) but its reciprocal is not even integrable.
$endgroup$
add a comment |
$begingroup$
Take $Omega:=(0,1)$ with Lebesgue measure and $X(omega):=omega$. $X$ is bounded, hence in all the $L^p$ (as $Omega$ has finite measure) but its reciprocal is not even integrable.
$endgroup$
add a comment |
$begingroup$
Take $Omega:=(0,1)$ with Lebesgue measure and $X(omega):=omega$. $X$ is bounded, hence in all the $L^p$ (as $Omega$ has finite measure) but its reciprocal is not even integrable.
$endgroup$
Take $Omega:=(0,1)$ with Lebesgue measure and $X(omega):=omega$. $X$ is bounded, hence in all the $L^p$ (as $Omega$ has finite measure) but its reciprocal is not even integrable.
edited Dec 7 '18 at 5:53
Drew Brady
712315
712315
answered Aug 15 '13 at 13:55
Davide GiraudoDavide Giraudo
126k16150261
126k16150261
add a comment |
add a comment |
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