What does $sum_{k=1}^{infty}X_k a_{n,k}$ exists almost surely for each $n$, actually mean?












1















Prove that $sum_{k=1}^{infty}X_k a_{n,k}$ exists almost surely for each $n$.




Is it that $Pbigg(displaystylelim_{nrightarrowinfty}sum_{k=1}^{infty}X_ka_{n,k}<inftybigg)=1$?



In this case $X_k$ is a sequence of random variables and $a_{n,k}$ are elements of a regular matrix.



I'm just confused on the wording, thanks!










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  • Yes. [More character for comment to appear.]
    – Will M.
    Nov 25 at 4:28










  • @WillM.: In future, try ${}{}{}{}{}$. It disappears.
    – Shaun
    Nov 25 at 4:29








  • 2




    I cannot make sense of the question. There is no $n$ in the statement, only $n_k$ -- how do these symbols relate?
    – Clement C.
    Nov 25 at 4:41










  • Actually double apologies, just to be clear, my question is written as $a_{nk}$ but what this must be referring to is $a_{n,k}$ so we're all clear then
    – OGV
    Nov 25 at 5:18










  • Proving that, for every fixed $n$, $mathbb{E}[sum_{k=1}^infty X_k a_{n,k}]$ exists would imply the result.
    – Clement C.
    Nov 25 at 5:28


















1















Prove that $sum_{k=1}^{infty}X_k a_{n,k}$ exists almost surely for each $n$.




Is it that $Pbigg(displaystylelim_{nrightarrowinfty}sum_{k=1}^{infty}X_ka_{n,k}<inftybigg)=1$?



In this case $X_k$ is a sequence of random variables and $a_{n,k}$ are elements of a regular matrix.



I'm just confused on the wording, thanks!










share|cite|improve this question
























  • Yes. [More character for comment to appear.]
    – Will M.
    Nov 25 at 4:28










  • @WillM.: In future, try ${}{}{}{}{}$. It disappears.
    – Shaun
    Nov 25 at 4:29








  • 2




    I cannot make sense of the question. There is no $n$ in the statement, only $n_k$ -- how do these symbols relate?
    – Clement C.
    Nov 25 at 4:41










  • Actually double apologies, just to be clear, my question is written as $a_{nk}$ but what this must be referring to is $a_{n,k}$ so we're all clear then
    – OGV
    Nov 25 at 5:18










  • Proving that, for every fixed $n$, $mathbb{E}[sum_{k=1}^infty X_k a_{n,k}]$ exists would imply the result.
    – Clement C.
    Nov 25 at 5:28
















1












1








1








Prove that $sum_{k=1}^{infty}X_k a_{n,k}$ exists almost surely for each $n$.




Is it that $Pbigg(displaystylelim_{nrightarrowinfty}sum_{k=1}^{infty}X_ka_{n,k}<inftybigg)=1$?



In this case $X_k$ is a sequence of random variables and $a_{n,k}$ are elements of a regular matrix.



I'm just confused on the wording, thanks!










share|cite|improve this question
















Prove that $sum_{k=1}^{infty}X_k a_{n,k}$ exists almost surely for each $n$.




Is it that $Pbigg(displaystylelim_{nrightarrowinfty}sum_{k=1}^{infty}X_ka_{n,k}<inftybigg)=1$?



In this case $X_k$ is a sequence of random variables and $a_{n,k}$ are elements of a regular matrix.



I'm just confused on the wording, thanks!







probability sequences-and-series measure-theory terminology definition






share|cite|improve this question















share|cite|improve this question













share|cite|improve this question




share|cite|improve this question








edited Nov 25 at 5:17

























asked Nov 25 at 4:23









OGV

497




497












  • Yes. [More character for comment to appear.]
    – Will M.
    Nov 25 at 4:28










  • @WillM.: In future, try ${}{}{}{}{}$. It disappears.
    – Shaun
    Nov 25 at 4:29








  • 2




    I cannot make sense of the question. There is no $n$ in the statement, only $n_k$ -- how do these symbols relate?
    – Clement C.
    Nov 25 at 4:41










  • Actually double apologies, just to be clear, my question is written as $a_{nk}$ but what this must be referring to is $a_{n,k}$ so we're all clear then
    – OGV
    Nov 25 at 5:18










  • Proving that, for every fixed $n$, $mathbb{E}[sum_{k=1}^infty X_k a_{n,k}]$ exists would imply the result.
    – Clement C.
    Nov 25 at 5:28




















  • Yes. [More character for comment to appear.]
    – Will M.
    Nov 25 at 4:28










  • @WillM.: In future, try ${}{}{}{}{}$. It disappears.
    – Shaun
    Nov 25 at 4:29








  • 2




    I cannot make sense of the question. There is no $n$ in the statement, only $n_k$ -- how do these symbols relate?
    – Clement C.
    Nov 25 at 4:41










  • Actually double apologies, just to be clear, my question is written as $a_{nk}$ but what this must be referring to is $a_{n,k}$ so we're all clear then
    – OGV
    Nov 25 at 5:18










  • Proving that, for every fixed $n$, $mathbb{E}[sum_{k=1}^infty X_k a_{n,k}]$ exists would imply the result.
    – Clement C.
    Nov 25 at 5:28


















Yes. [More character for comment to appear.]
– Will M.
Nov 25 at 4:28




Yes. [More character for comment to appear.]
– Will M.
Nov 25 at 4:28












@WillM.: In future, try ${}{}{}{}{}$. It disappears.
– Shaun
Nov 25 at 4:29






@WillM.: In future, try ${}{}{}{}{}$. It disappears.
– Shaun
Nov 25 at 4:29






2




2




I cannot make sense of the question. There is no $n$ in the statement, only $n_k$ -- how do these symbols relate?
– Clement C.
Nov 25 at 4:41




I cannot make sense of the question. There is no $n$ in the statement, only $n_k$ -- how do these symbols relate?
– Clement C.
Nov 25 at 4:41












Actually double apologies, just to be clear, my question is written as $a_{nk}$ but what this must be referring to is $a_{n,k}$ so we're all clear then
– OGV
Nov 25 at 5:18




Actually double apologies, just to be clear, my question is written as $a_{nk}$ but what this must be referring to is $a_{n,k}$ so we're all clear then
– OGV
Nov 25 at 5:18












Proving that, for every fixed $n$, $mathbb{E}[sum_{k=1}^infty X_k a_{n,k}]$ exists would imply the result.
– Clement C.
Nov 25 at 5:28






Proving that, for every fixed $n$, $mathbb{E}[sum_{k=1}^infty X_k a_{n,k}]$ exists would imply the result.
– Clement C.
Nov 25 at 5:28

















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