Expectation in a stochastic differential equation The Next CEO of Stack OverflowWhat is Ito's...

Help! I cannot understand this game’s notations!

Does Germany produce more waste than the US?

In the "Harry Potter and the Order of the Phoenix" video game, what potion is used to sabotage Umbridge's speakers?

Why is the US ranked as #45 in Press Freedom ratings, despite its extremely permissive free speech laws?

If Nick Fury and Coulson already knew about aliens (Kree and Skrull) why did they wait until Thor's appearance to start making weapons?

Pulling the principal components out of a DimensionReducerFunction?

Why don't programming languages automatically manage the synchronous/asynchronous problem?

How to find image of a complex function with given constraints?

AB diagonalizable then BA also diagonalizable

Defamation due to breach of confidentiality

Are the names of these months realistic?

What was Carter Burke's job for "the company" in Aliens?

Calculate the Mean mean of two numbers

Film where the government was corrupt with aliens, people sent to kill aliens are given rigged visors not showing the right aliens

Is there a reasonable and studied concept of reduction between regular languages?

Is French Guiana a (hard) EU border?

Traveling with my 5 year old daughter (as the father) without the mother from Germany to Mexico

Is it professional to write unrelated content in an almost-empty email?

What does "shotgun unity" refer to here in this sentence?

Is it correct to say moon starry nights?

What day is it again?

Would a grinding machine be a simple and workable propulsion system for an interplanetary spacecraft?

Does the Idaho Potato Commission associate potato skins with healthy eating?

What happened in Rome, when the western empire "fell"?



Expectation in a stochastic differential equation



The Next CEO of Stack OverflowWhat is Ito's lemma used for in quantitative finance?Question about the stochastic differential equation in the Merton modelComputation of ExpectationSquare of arithmetic brownian motion processBaxter & Rennie HJM: differentiating Ito integralSimple HJM model, differentiating the bond priceStochastic Leibniz ruleStochastic differential equation of a Brownian MotionHow to calculate the product of forward rates with different reset times using Ito's lemma?For an Ito Process, $dln{X} neq frac{dX}{X}$ and $(dln{X})^2 = (frac{dX}{X})^2$, but $dln{X} neq pm frac{dX}{X}$












2












$begingroup$


I'm new to stochastic calculus, I want to find the mean of $X_2$ with $X_t = exp(W_t)$, with $W_t$ a Wiener process.



I used Ito's Lemma is arrive at the SDE:
begin{align}
d(X_t) = frac{1}{2}X_t dt + X_t dW_t
end{align}

But how can I get the mean of $X_2$?










share|improve this question











$endgroup$

















    2












    $begingroup$


    I'm new to stochastic calculus, I want to find the mean of $X_2$ with $X_t = exp(W_t)$, with $W_t$ a Wiener process.



    I used Ito's Lemma is arrive at the SDE:
    begin{align}
    d(X_t) = frac{1}{2}X_t dt + X_t dW_t
    end{align}

    But how can I get the mean of $X_2$?










    share|improve this question











    $endgroup$















      2












      2








      2


      1



      $begingroup$


      I'm new to stochastic calculus, I want to find the mean of $X_2$ with $X_t = exp(W_t)$, with $W_t$ a Wiener process.



      I used Ito's Lemma is arrive at the SDE:
      begin{align}
      d(X_t) = frac{1}{2}X_t dt + X_t dW_t
      end{align}

      But how can I get the mean of $X_2$?










      share|improve this question











      $endgroup$




      I'm new to stochastic calculus, I want to find the mean of $X_2$ with $X_t = exp(W_t)$, with $W_t$ a Wiener process.



      I used Ito's Lemma is arrive at the SDE:
      begin{align}
      d(X_t) = frac{1}{2}X_t dt + X_t dW_t
      end{align}

      But how can I get the mean of $X_2$?







      itos-lemma sde






      share|improve this question















      share|improve this question













      share|improve this question




      share|improve this question








      edited 4 hours ago







      Victor

















      asked 5 hours ago









      VictorVictor

      614




      614






















          1 Answer
          1






          active

          oldest

          votes


















          2












          $begingroup$

          Assuming you are talking about unconditional expectation, in general you have



          $$
          mathbb{E}[X_t] = mathbb{E}[e^{W_t}] = e^{mathbb{E}[W_t] + frac{1}{2}text{Var}(W_t) }
          $$



          which yields



          $$
          mathbb{E}[X_t]= e^{frac{1}{2} t}
          $$



          Hence,



          $$ mathbb{E}[X_2]= e $$






          share|improve this answer








          New contributor




          RafaelC is a new contributor to this site. Take care in asking for clarification, commenting, and answering.
          Check out our Code of Conduct.






          $endgroup$













          • $begingroup$
            I'm quite new to the theory. What is the name of the first equality and under which hypotheses is it true?
            $endgroup$
            – Victor
            4 hours ago






          • 1




            $begingroup$
            @Victor the first equality comes from the moment-generating function of a normal. Take a look here for more details. In general, $mathbb{E}[e^X] = e^{mu + frac{1}{2} sigma^2}$ holds whenever $X sim mathcal{N}(mu, sigma^2)$
            $endgroup$
            – RafaelC
            4 hours ago












          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: "204"
          };
          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: false,
          noModals: true,
          showLowRepImageUploadWarning: true,
          reputationToPostImages: null,
          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%2fquant.stackexchange.com%2fquestions%2f44854%2fexpectation-in-a-stochastic-differential-equation%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









          2












          $begingroup$

          Assuming you are talking about unconditional expectation, in general you have



          $$
          mathbb{E}[X_t] = mathbb{E}[e^{W_t}] = e^{mathbb{E}[W_t] + frac{1}{2}text{Var}(W_t) }
          $$



          which yields



          $$
          mathbb{E}[X_t]= e^{frac{1}{2} t}
          $$



          Hence,



          $$ mathbb{E}[X_2]= e $$






          share|improve this answer








          New contributor




          RafaelC is a new contributor to this site. Take care in asking for clarification, commenting, and answering.
          Check out our Code of Conduct.






          $endgroup$













          • $begingroup$
            I'm quite new to the theory. What is the name of the first equality and under which hypotheses is it true?
            $endgroup$
            – Victor
            4 hours ago






          • 1




            $begingroup$
            @Victor the first equality comes from the moment-generating function of a normal. Take a look here for more details. In general, $mathbb{E}[e^X] = e^{mu + frac{1}{2} sigma^2}$ holds whenever $X sim mathcal{N}(mu, sigma^2)$
            $endgroup$
            – RafaelC
            4 hours ago
















          2












          $begingroup$

          Assuming you are talking about unconditional expectation, in general you have



          $$
          mathbb{E}[X_t] = mathbb{E}[e^{W_t}] = e^{mathbb{E}[W_t] + frac{1}{2}text{Var}(W_t) }
          $$



          which yields



          $$
          mathbb{E}[X_t]= e^{frac{1}{2} t}
          $$



          Hence,



          $$ mathbb{E}[X_2]= e $$






          share|improve this answer








          New contributor




          RafaelC is a new contributor to this site. Take care in asking for clarification, commenting, and answering.
          Check out our Code of Conduct.






          $endgroup$













          • $begingroup$
            I'm quite new to the theory. What is the name of the first equality and under which hypotheses is it true?
            $endgroup$
            – Victor
            4 hours ago






          • 1




            $begingroup$
            @Victor the first equality comes from the moment-generating function of a normal. Take a look here for more details. In general, $mathbb{E}[e^X] = e^{mu + frac{1}{2} sigma^2}$ holds whenever $X sim mathcal{N}(mu, sigma^2)$
            $endgroup$
            – RafaelC
            4 hours ago














          2












          2








          2





          $begingroup$

          Assuming you are talking about unconditional expectation, in general you have



          $$
          mathbb{E}[X_t] = mathbb{E}[e^{W_t}] = e^{mathbb{E}[W_t] + frac{1}{2}text{Var}(W_t) }
          $$



          which yields



          $$
          mathbb{E}[X_t]= e^{frac{1}{2} t}
          $$



          Hence,



          $$ mathbb{E}[X_2]= e $$






          share|improve this answer








          New contributor




          RafaelC is a new contributor to this site. Take care in asking for clarification, commenting, and answering.
          Check out our Code of Conduct.






          $endgroup$



          Assuming you are talking about unconditional expectation, in general you have



          $$
          mathbb{E}[X_t] = mathbb{E}[e^{W_t}] = e^{mathbb{E}[W_t] + frac{1}{2}text{Var}(W_t) }
          $$



          which yields



          $$
          mathbb{E}[X_t]= e^{frac{1}{2} t}
          $$



          Hence,



          $$ mathbb{E}[X_2]= e $$







          share|improve this answer








          New contributor




          RafaelC is a new contributor to this site. Take care in asking for clarification, commenting, and answering.
          Check out our Code of Conduct.









          share|improve this answer



          share|improve this answer






          New contributor




          RafaelC is a new contributor to this site. Take care in asking for clarification, commenting, and answering.
          Check out our Code of Conduct.









          answered 4 hours ago









          RafaelCRafaelC

          1363




          1363




          New contributor




          RafaelC is a new contributor to this site. Take care in asking for clarification, commenting, and answering.
          Check out our Code of Conduct.





          New contributor





          RafaelC is a new contributor to this site. Take care in asking for clarification, commenting, and answering.
          Check out our Code of Conduct.






          RafaelC is a new contributor to this site. Take care in asking for clarification, commenting, and answering.
          Check out our Code of Conduct.












          • $begingroup$
            I'm quite new to the theory. What is the name of the first equality and under which hypotheses is it true?
            $endgroup$
            – Victor
            4 hours ago






          • 1




            $begingroup$
            @Victor the first equality comes from the moment-generating function of a normal. Take a look here for more details. In general, $mathbb{E}[e^X] = e^{mu + frac{1}{2} sigma^2}$ holds whenever $X sim mathcal{N}(mu, sigma^2)$
            $endgroup$
            – RafaelC
            4 hours ago


















          • $begingroup$
            I'm quite new to the theory. What is the name of the first equality and under which hypotheses is it true?
            $endgroup$
            – Victor
            4 hours ago






          • 1




            $begingroup$
            @Victor the first equality comes from the moment-generating function of a normal. Take a look here for more details. In general, $mathbb{E}[e^X] = e^{mu + frac{1}{2} sigma^2}$ holds whenever $X sim mathcal{N}(mu, sigma^2)$
            $endgroup$
            – RafaelC
            4 hours ago
















          $begingroup$
          I'm quite new to the theory. What is the name of the first equality and under which hypotheses is it true?
          $endgroup$
          – Victor
          4 hours ago




          $begingroup$
          I'm quite new to the theory. What is the name of the first equality and under which hypotheses is it true?
          $endgroup$
          – Victor
          4 hours ago




          1




          1




          $begingroup$
          @Victor the first equality comes from the moment-generating function of a normal. Take a look here for more details. In general, $mathbb{E}[e^X] = e^{mu + frac{1}{2} sigma^2}$ holds whenever $X sim mathcal{N}(mu, sigma^2)$
          $endgroup$
          – RafaelC
          4 hours ago




          $begingroup$
          @Victor the first equality comes from the moment-generating function of a normal. Take a look here for more details. In general, $mathbb{E}[e^X] = e^{mu + frac{1}{2} sigma^2}$ holds whenever $X sim mathcal{N}(mu, sigma^2)$
          $endgroup$
          – RafaelC
          4 hours ago


















          draft saved

          draft discarded




















































          Thanks for contributing an answer to Quantitative Finance 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%2fquant.stackexchange.com%2fquestions%2f44854%2fexpectation-in-a-stochastic-differential-equation%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

          Щит и меч (фильм) Содержание Названия серий | Сюжет |...

          is 'sed' thread safeWhat should someone know about using Python scripts in the shell?Nexenta bash script uses...

          Meter-Bus Содержание Параметры шины | Стандартизация |...