Lebesgue convergence theorem extension (random variables)Martingale convergence almost surelyLebesgue Convergence TheoremNon-negativity in Fatou's Lemma and Lebesgue Dominated Convergence TheoremAbout Vitali Convergence Theorem and Uniform IntegrabilityProve the monotone convergence theorem for sequences of Lebesgue-integrable functionsTheoretical Advantages of Lebesgue IntegrationFunctions involving expectations - The dominated/monotone convergence theoremAn counterexample for the monotone convergence theorem and dominated convergence theoremConvergence of Riemann integralUsing the Lebesgue dominated convergence theorem

What is a Samsaran Word™?

Should I tell management that I intend to leave due to bad software development practices?

Forgetting the musical notes while performing in concert

What do you call someone who asks many questions?

Can someone clarify Hamming's notion of important problems in relation to modern academia?

Car headlights in a world without electricity

Can compressed videos be decoded back to their uncompresed original format?

Do Iron Man suits sport waste management systems?

Was the old ablative pronoun "med" or "mēd"?

how do we prove that a sum of two periods is still a period?

How can a day be of 24 hours?

Why was the shrink from 8″ made only to 5.25″ and not smaller (4″ or less)

How badly should I try to prevent a user from XSSing themselves?

Machine learning testing data

My ex-girlfriend uses my Apple ID to log in to her iPad. Do I have to give her my Apple ID password to reset it?

Sums of two squares in arithmetic progressions

What is required to make GPS signals available indoors?

GFCI outlets - can they be repaired? Are they really needed at the end of a circuit?

Ambiguity in the definition of entropy

Rotate ASCII Art by 45 Degrees

What's the meaning of "Sollensaussagen"?

Notepad++ delete until colon for every line with replace all

Is it "common practice in Fourier transform spectroscopy to multiply the measured interferogram by an apodizing function"? If so, why?

Getting extremely large arrows with tikzcd



Lebesgue convergence theorem extension (random variables)


Martingale convergence almost surelyLebesgue Convergence TheoremNon-negativity in Fatou's Lemma and Lebesgue Dominated Convergence TheoremAbout Vitali Convergence Theorem and Uniform IntegrabilityProve the monotone convergence theorem for sequences of Lebesgue-integrable functionsTheoretical Advantages of Lebesgue IntegrationFunctions involving expectations - The dominated/monotone convergence theoremAn counterexample for the monotone convergence theorem and dominated convergence theoremConvergence of Riemann integralUsing the Lebesgue dominated convergence theorem













0












$begingroup$


Let $Z$ be a lower semi integrable r.v. and $W_n$ a sequence of bounded r.v increasing and dominated by another bounded r.v from above $W_n leq W$, why is true that $E[ZW_n]$ converges to $E[ZW]$?



The negative part $Z^-$ is taken care of by the standard Lebesgue convergence theorem, but the positive part $Z^+W_n$ I don't know how to make it converge since it may be negative.



This was used in the book of Paolo Baldi: Stochastic Calculus page 88. He uses the monotone class theorem to prove that to find the conditional expectation it is sufficient to check for a class generating the sigma algebra, stable with respect to finite intersections.



Thanks.



Taking the lebesgue measure in $[0,1]$, $lambda$, $Z=dfrac1x$, $W_n = -dfrac1n$, one can see that the integral sequence doesn't even exist.










share|cite|improve this question











$endgroup$
















    0












    $begingroup$


    Let $Z$ be a lower semi integrable r.v. and $W_n$ a sequence of bounded r.v increasing and dominated by another bounded r.v from above $W_n leq W$, why is true that $E[ZW_n]$ converges to $E[ZW]$?



    The negative part $Z^-$ is taken care of by the standard Lebesgue convergence theorem, but the positive part $Z^+W_n$ I don't know how to make it converge since it may be negative.



    This was used in the book of Paolo Baldi: Stochastic Calculus page 88. He uses the monotone class theorem to prove that to find the conditional expectation it is sufficient to check for a class generating the sigma algebra, stable with respect to finite intersections.



    Thanks.



    Taking the lebesgue measure in $[0,1]$, $lambda$, $Z=dfrac1x$, $W_n = -dfrac1n$, one can see that the integral sequence doesn't even exist.










    share|cite|improve this question











    $endgroup$














      0












      0








      0





      $begingroup$


      Let $Z$ be a lower semi integrable r.v. and $W_n$ a sequence of bounded r.v increasing and dominated by another bounded r.v from above $W_n leq W$, why is true that $E[ZW_n]$ converges to $E[ZW]$?



      The negative part $Z^-$ is taken care of by the standard Lebesgue convergence theorem, but the positive part $Z^+W_n$ I don't know how to make it converge since it may be negative.



      This was used in the book of Paolo Baldi: Stochastic Calculus page 88. He uses the monotone class theorem to prove that to find the conditional expectation it is sufficient to check for a class generating the sigma algebra, stable with respect to finite intersections.



      Thanks.



      Taking the lebesgue measure in $[0,1]$, $lambda$, $Z=dfrac1x$, $W_n = -dfrac1n$, one can see that the integral sequence doesn't even exist.










      share|cite|improve this question











      $endgroup$




      Let $Z$ be a lower semi integrable r.v. and $W_n$ a sequence of bounded r.v increasing and dominated by another bounded r.v from above $W_n leq W$, why is true that $E[ZW_n]$ converges to $E[ZW]$?



      The negative part $Z^-$ is taken care of by the standard Lebesgue convergence theorem, but the positive part $Z^+W_n$ I don't know how to make it converge since it may be negative.



      This was used in the book of Paolo Baldi: Stochastic Calculus page 88. He uses the monotone class theorem to prove that to find the conditional expectation it is sufficient to check for a class generating the sigma algebra, stable with respect to finite intersections.



      Thanks.



      Taking the lebesgue measure in $[0,1]$, $lambda$, $Z=dfrac1x$, $W_n = -dfrac1n$, one can see that the integral sequence doesn't even exist.







      real-analysis probability-theory convergence lebesgue-integral






      share|cite|improve this question















      share|cite|improve this question













      share|cite|improve this question




      share|cite|improve this question








      edited Mar 20 at 18:55







      lucmobz

















      asked Mar 20 at 18:37









      lucmobzlucmobz

      404




      404




















          1 Answer
          1






          active

          oldest

          votes


















          0












          $begingroup$

          It seems that Remark 4.2 refers to integrable random variables $X$ and $Z$. Proceeding with your example, where $([0,1],mathcalB_[0,1],lambda)$ is the prob. space and $Z(omega)=omega^-1times 1omega>0$, take $W_n(omega)=-1_[0,n^-1)(omega)$. Then $Z$ is l.s.i., $-1le W_nle 0$, and $W_nnearrow 0$. However,
          $$
          0=mathsfEWZnelim_ntoinftymathsfEW_nZ=-infty.
          $$






          share|cite|improve this answer









          $endgroup$












          • $begingroup$
            For the same reason one can only extend the $E[ZW]=E[XW]$ property to all bounded measurable functions when $X$ is integrable, and also when he talks about the expectation function given a random variable he assumes integrability when he says "for all bounded (l.s.i. is just bounded positive) measurable"? Thanks for clarifying, the book was a bit unclear there.
            $endgroup$
            – lucmobz
            Mar 20 at 22:31












          Your Answer





          StackExchange.ifUsing("editor", function ()
          return StackExchange.using("mathjaxEditing", function ()
          StackExchange.MarkdownEditor.creationCallbacks.add(function (editor, postfix)
          StackExchange.mathjaxEditing.prepareWmdForMathJax(editor, postfix, [["$", "$"], ["\\(","\\)"]]);
          );
          );
          , "mathjax-editing");

          StackExchange.ready(function()
          var channelOptions =
          tags: "".split(" "),
          id: "69"
          ;
          initTagRenderer("".split(" "), "".split(" "), channelOptions);

          StackExchange.using("externalEditor", function()
          // Have to fire editor after snippets, if snippets enabled
          if (StackExchange.settings.snippets.snippetsEnabled)
          StackExchange.using("snippets", function()
          createEditor();
          );

          else
          createEditor();

          );

          function createEditor()
          StackExchange.prepareEditor(
          heartbeatType: 'answer',
          autoActivateHeartbeat: false,
          convertImagesToLinks: true,
          noModals: true,
          showLowRepImageUploadWarning: true,
          reputationToPostImages: 10,
          bindNavPrevention: true,
          postfix: "",
          imageUploader:
          brandingHtml: "Powered by u003ca class="icon-imgur-white" href="https://imgur.com/"u003eu003c/au003e",
          contentPolicyHtml: "User contributions licensed under u003ca href="https://creativecommons.org/licenses/by-sa/3.0/"u003ecc by-sa 3.0 with attribution requiredu003c/au003e u003ca href="https://stackoverflow.com/legal/content-policy"u003e(content policy)u003c/au003e",
          allowUrls: true
          ,
          noCode: true, onDemand: true,
          discardSelector: ".discard-answer"
          ,immediatelyShowMarkdownHelp:true
          );



          );













          draft saved

          draft discarded


















          StackExchange.ready(
          function ()
          StackExchange.openid.initPostLogin('.new-post-login', 'https%3a%2f%2fmath.stackexchange.com%2fquestions%2f3155852%2flebesgue-convergence-theorem-extension-random-variables%23new-answer', 'question_page');

          );

          Post as a guest















          Required, but never shown

























          1 Answer
          1






          active

          oldest

          votes








          1 Answer
          1






          active

          oldest

          votes









          active

          oldest

          votes






          active

          oldest

          votes









          0












          $begingroup$

          It seems that Remark 4.2 refers to integrable random variables $X$ and $Z$. Proceeding with your example, where $([0,1],mathcalB_[0,1],lambda)$ is the prob. space and $Z(omega)=omega^-1times 1omega>0$, take $W_n(omega)=-1_[0,n^-1)(omega)$. Then $Z$ is l.s.i., $-1le W_nle 0$, and $W_nnearrow 0$. However,
          $$
          0=mathsfEWZnelim_ntoinftymathsfEW_nZ=-infty.
          $$






          share|cite|improve this answer









          $endgroup$












          • $begingroup$
            For the same reason one can only extend the $E[ZW]=E[XW]$ property to all bounded measurable functions when $X$ is integrable, and also when he talks about the expectation function given a random variable he assumes integrability when he says "for all bounded (l.s.i. is just bounded positive) measurable"? Thanks for clarifying, the book was a bit unclear there.
            $endgroup$
            – lucmobz
            Mar 20 at 22:31
















          0












          $begingroup$

          It seems that Remark 4.2 refers to integrable random variables $X$ and $Z$. Proceeding with your example, where $([0,1],mathcalB_[0,1],lambda)$ is the prob. space and $Z(omega)=omega^-1times 1omega>0$, take $W_n(omega)=-1_[0,n^-1)(omega)$. Then $Z$ is l.s.i., $-1le W_nle 0$, and $W_nnearrow 0$. However,
          $$
          0=mathsfEWZnelim_ntoinftymathsfEW_nZ=-infty.
          $$






          share|cite|improve this answer









          $endgroup$












          • $begingroup$
            For the same reason one can only extend the $E[ZW]=E[XW]$ property to all bounded measurable functions when $X$ is integrable, and also when he talks about the expectation function given a random variable he assumes integrability when he says "for all bounded (l.s.i. is just bounded positive) measurable"? Thanks for clarifying, the book was a bit unclear there.
            $endgroup$
            – lucmobz
            Mar 20 at 22:31














          0












          0








          0





          $begingroup$

          It seems that Remark 4.2 refers to integrable random variables $X$ and $Z$. Proceeding with your example, where $([0,1],mathcalB_[0,1],lambda)$ is the prob. space and $Z(omega)=omega^-1times 1omega>0$, take $W_n(omega)=-1_[0,n^-1)(omega)$. Then $Z$ is l.s.i., $-1le W_nle 0$, and $W_nnearrow 0$. However,
          $$
          0=mathsfEWZnelim_ntoinftymathsfEW_nZ=-infty.
          $$






          share|cite|improve this answer









          $endgroup$



          It seems that Remark 4.2 refers to integrable random variables $X$ and $Z$. Proceeding with your example, where $([0,1],mathcalB_[0,1],lambda)$ is the prob. space and $Z(omega)=omega^-1times 1omega>0$, take $W_n(omega)=-1_[0,n^-1)(omega)$. Then $Z$ is l.s.i., $-1le W_nle 0$, and $W_nnearrow 0$. However,
          $$
          0=mathsfEWZnelim_ntoinftymathsfEW_nZ=-infty.
          $$







          share|cite|improve this answer












          share|cite|improve this answer



          share|cite|improve this answer










          answered Mar 20 at 21:12









          d.k.o.d.k.o.

          10.5k630




          10.5k630











          • $begingroup$
            For the same reason one can only extend the $E[ZW]=E[XW]$ property to all bounded measurable functions when $X$ is integrable, and also when he talks about the expectation function given a random variable he assumes integrability when he says "for all bounded (l.s.i. is just bounded positive) measurable"? Thanks for clarifying, the book was a bit unclear there.
            $endgroup$
            – lucmobz
            Mar 20 at 22:31

















          • $begingroup$
            For the same reason one can only extend the $E[ZW]=E[XW]$ property to all bounded measurable functions when $X$ is integrable, and also when he talks about the expectation function given a random variable he assumes integrability when he says "for all bounded (l.s.i. is just bounded positive) measurable"? Thanks for clarifying, the book was a bit unclear there.
            $endgroup$
            – lucmobz
            Mar 20 at 22:31
















          $begingroup$
          For the same reason one can only extend the $E[ZW]=E[XW]$ property to all bounded measurable functions when $X$ is integrable, and also when he talks about the expectation function given a random variable he assumes integrability when he says "for all bounded (l.s.i. is just bounded positive) measurable"? Thanks for clarifying, the book was a bit unclear there.
          $endgroup$
          – lucmobz
          Mar 20 at 22:31





          $begingroup$
          For the same reason one can only extend the $E[ZW]=E[XW]$ property to all bounded measurable functions when $X$ is integrable, and also when he talks about the expectation function given a random variable he assumes integrability when he says "for all bounded (l.s.i. is just bounded positive) measurable"? Thanks for clarifying, the book was a bit unclear there.
          $endgroup$
          – lucmobz
          Mar 20 at 22:31


















          draft saved

          draft discarded
















































          Thanks for contributing an answer to Mathematics Stack Exchange!


          • Please be sure to answer the question. Provide details and share your research!

          But avoid


          • Asking for help, clarification, or responding to other answers.

          • Making statements based on opinion; back them up with references or personal experience.

          Use MathJax to format equations. MathJax reference.


          To learn more, see our tips on writing great answers.




          draft saved


          draft discarded














          StackExchange.ready(
          function ()
          StackExchange.openid.initPostLogin('.new-post-login', 'https%3a%2f%2fmath.stackexchange.com%2fquestions%2f3155852%2flebesgue-convergence-theorem-extension-random-variables%23new-answer', 'question_page');

          );

          Post as a guest















          Required, but never shown





















































          Required, but never shown














          Required, but never shown












          Required, but never shown







          Required, but never shown

































          Required, but never shown














          Required, but never shown












          Required, but never shown







          Required, but never shown







          Popular posts from this blog

          Lowndes Grove History Architecture References Navigation menu32°48′6″N 79°57′58″W / 32.80167°N 79.96611°W / 32.80167; -79.9661132°48′6″N 79°57′58″W / 32.80167°N 79.96611°W / 32.80167; -79.9661178002500"National Register Information System"Historic houses of South Carolina"Lowndes Grove""+32° 48' 6.00", −79° 57' 58.00""Lowndes Grove, Charleston County (260 St. Margaret St., Charleston)""Lowndes Grove"The Charleston ExpositionIt Happened in South Carolina"Lowndes Grove (House), Saint Margaret Street & Sixth Avenue, Charleston, Charleston County, SC(Photographs)"Plantations of the Carolina Low Countrye

          random experiment with two different functions on unit interval Announcing the arrival of Valued Associate #679: Cesar Manara Planned maintenance scheduled April 23, 2019 at 00:00UTC (8:00pm US/Eastern)Random variable and probability space notionsRandom Walk with EdgesFinding functions where the increase over a random interval is Poisson distributedNumber of days until dayCan an observed event in fact be of zero probability?Unit random processmodels of coins and uniform distributionHow to get the number of successes given $n$ trials , probability $P$ and a random variable $X$Absorbing Markov chain in a computer. Is “almost every” turned into always convergence in computer executions?Stopped random walk is not uniformly integrable

          How should I support this large drywall patch? Planned maintenance scheduled April 23, 2019 at 00:00UTC (8:00pm US/Eastern) Announcing the arrival of Valued Associate #679: Cesar Manara Unicorn Meta Zoo #1: Why another podcast?How do I cover large gaps in drywall?How do I keep drywall around a patch from crumbling?Can I glue a second layer of drywall?How to patch long strip on drywall?Large drywall patch: how to avoid bulging seams?Drywall Mesh Patch vs. Bulge? To remove or not to remove?How to fix this drywall job?Prep drywall before backsplashWhat's the best way to fix this horrible drywall patch job?Drywall patching using 3M Patch Plus Primer