Problem at deriving Bachelier formula with interest ratesWhy is the black-scholes model arbitrage free when σ>0?Square of arithmetic brownian motion processStochastic process and brownian motionpricing option with two stocksChange-of-measure: Dynamics of $log(S_t)$ with $S_t$ as numeraireBlack & Scholes with stochastic interest ratePricing caplet with Bachelier (normal dynamic) using forward measureQuestion about Stochastic Calculus,(change of measure)?Ultra Powerfull Vibrato Montecarlo for delta sensitivities of a not regular payoffEquivalence of Put Pricing Formulas

Why do most airliners have underwing engines, while business jets have rear-mounted engines?

What's the difference between a type and a kind?

When is one 'Ready' to make Original Contributions to Mathematics?

How can I effectively map a multi-level dungeon?

Was I wrongfully denied boarding for having a Schengen visa issued from the second country on my itinerary?

How important is it for multiple POVs to run chronologically?

Do intermediate subdomains need to exist?

Why do we need a bootloader separate from our application program in microcontrollers?

The Purpose of "Natu"

What instances can be solved today by modern solvers (pure LP)?

How did Captain Marvel do this without dying?

Why did Super-VGA offer the 5:4 1280*1024 resolution?

Why no parachutes in the Orion AA2 abort test?

Is there a standard definition of the "stall" phenomena?

/api/sitecore is not working in CD server

Isn't "Dave's protocol" good if only the database, and not the code, is leaked?

Is this standard Japanese employment negotiations, or am I missing something?

Taking my Ph.D. advisor out for dinner after graduation

Red and White Squares

Advice for making/keeping shredded chicken moist?

Do the 26 richest billionaires own as much wealth as the poorest 3.8 billion people?

Was the 45.9°C temperature in France in June 2019 the highest ever recorded in France?

What do you call the angle of the direction of an airplane?

How come a desk dictionary be abridged?



Problem at deriving Bachelier formula with interest rates


Why is the black-scholes model arbitrage free when σ>0?Square of arithmetic brownian motion processStochastic process and brownian motionpricing option with two stocksChange-of-measure: Dynamics of $log(S_t)$ with $S_t$ as numeraireBlack & Scholes with stochastic interest ratePricing caplet with Bachelier (normal dynamic) using forward measureQuestion about Stochastic Calculus,(change of measure)?Ultra Powerfull Vibrato Montecarlo for delta sensitivities of a not regular payoffEquivalence of Put Pricing Formulas






.everyoneloves__top-leaderboard:empty,.everyoneloves__mid-leaderboard:empty,.everyoneloves__bot-mid-leaderboard:empty margin-bottom:0;








3












$begingroup$


In the Bachelier model, I have difficulties with a certain step. I want to figure out the distribution of $S_T$, which is the price process in the Bachelier model.



So far I could state that ($mathbbQ$ is the EMM):
begineqnarray
dS_t = r S_t dt + sigma W^mathbbQ_t labelSDE2
endeqnarray

and with that
begineqnarray
S_T = S_0 e^rT + intlimits_0^Tsigma e^r(T-s) dW^mathbbQ_s
endeqnarray

Now I have found a book that states that $S_T$ has distribution:
begineqnarray
S_T sim mathscr N left(S_0 e^rT, sqrtfracsigma^2-sigma^2e^-2rT2r right)
endeqnarray



I do not understand why this should be, maybe my skills in stochastic integration are not sufficient.



Thank you for taking your time!










share|improve this question











$endgroup$







  • 4




    $begingroup$
    This is a direct application of Ito's isometry: en.m.wikipedia.org/wiki/It%C3%B4_isometry it gives you the mean (= 0) and variance ($= int f^2(u)du$) of a Wiener integral $int f(u) dW(u)$.
    $endgroup$
    – byouness
    Jun 26 at 8:00


















3












$begingroup$


In the Bachelier model, I have difficulties with a certain step. I want to figure out the distribution of $S_T$, which is the price process in the Bachelier model.



So far I could state that ($mathbbQ$ is the EMM):
begineqnarray
dS_t = r S_t dt + sigma W^mathbbQ_t labelSDE2
endeqnarray

and with that
begineqnarray
S_T = S_0 e^rT + intlimits_0^Tsigma e^r(T-s) dW^mathbbQ_s
endeqnarray

Now I have found a book that states that $S_T$ has distribution:
begineqnarray
S_T sim mathscr N left(S_0 e^rT, sqrtfracsigma^2-sigma^2e^-2rT2r right)
endeqnarray



I do not understand why this should be, maybe my skills in stochastic integration are not sufficient.



Thank you for taking your time!










share|improve this question











$endgroup$







  • 4




    $begingroup$
    This is a direct application of Ito's isometry: en.m.wikipedia.org/wiki/It%C3%B4_isometry it gives you the mean (= 0) and variance ($= int f^2(u)du$) of a Wiener integral $int f(u) dW(u)$.
    $endgroup$
    – byouness
    Jun 26 at 8:00














3












3








3


1



$begingroup$


In the Bachelier model, I have difficulties with a certain step. I want to figure out the distribution of $S_T$, which is the price process in the Bachelier model.



So far I could state that ($mathbbQ$ is the EMM):
begineqnarray
dS_t = r S_t dt + sigma W^mathbbQ_t labelSDE2
endeqnarray

and with that
begineqnarray
S_T = S_0 e^rT + intlimits_0^Tsigma e^r(T-s) dW^mathbbQ_s
endeqnarray

Now I have found a book that states that $S_T$ has distribution:
begineqnarray
S_T sim mathscr N left(S_0 e^rT, sqrtfracsigma^2-sigma^2e^-2rT2r right)
endeqnarray



I do not understand why this should be, maybe my skills in stochastic integration are not sufficient.



Thank you for taking your time!










share|improve this question











$endgroup$




In the Bachelier model, I have difficulties with a certain step. I want to figure out the distribution of $S_T$, which is the price process in the Bachelier model.



So far I could state that ($mathbbQ$ is the EMM):
begineqnarray
dS_t = r S_t dt + sigma W^mathbbQ_t labelSDE2
endeqnarray

and with that
begineqnarray
S_T = S_0 e^rT + intlimits_0^Tsigma e^r(T-s) dW^mathbbQ_s
endeqnarray

Now I have found a book that states that $S_T$ has distribution:
begineqnarray
S_T sim mathscr N left(S_0 e^rT, sqrtfracsigma^2-sigma^2e^-2rT2r right)
endeqnarray



I do not understand why this should be, maybe my skills in stochastic integration are not sufficient.



Thank you for taking your time!







options stochastic-calculus pricing models






share|improve this question















share|improve this question













share|improve this question




share|improve this question








edited Jun 26 at 7:48







cruiser0223

















asked Jun 26 at 7:43









cruiser0223cruiser0223

184 bronze badges




184 bronze badges







  • 4




    $begingroup$
    This is a direct application of Ito's isometry: en.m.wikipedia.org/wiki/It%C3%B4_isometry it gives you the mean (= 0) and variance ($= int f^2(u)du$) of a Wiener integral $int f(u) dW(u)$.
    $endgroup$
    – byouness
    Jun 26 at 8:00













  • 4




    $begingroup$
    This is a direct application of Ito's isometry: en.m.wikipedia.org/wiki/It%C3%B4_isometry it gives you the mean (= 0) and variance ($= int f^2(u)du$) of a Wiener integral $int f(u) dW(u)$.
    $endgroup$
    – byouness
    Jun 26 at 8:00








4




4




$begingroup$
This is a direct application of Ito's isometry: en.m.wikipedia.org/wiki/It%C3%B4_isometry it gives you the mean (= 0) and variance ($= int f^2(u)du$) of a Wiener integral $int f(u) dW(u)$.
$endgroup$
– byouness
Jun 26 at 8:00





$begingroup$
This is a direct application of Ito's isometry: en.m.wikipedia.org/wiki/It%C3%B4_isometry it gives you the mean (= 0) and variance ($= int f^2(u)du$) of a Wiener integral $int f(u) dW(u)$.
$endgroup$
– byouness
Jun 26 at 8:00











1 Answer
1






active

oldest

votes


















4












$begingroup$

As explained by @byouness, using Itô's Isometry, we get:
$$beginalign
V(S_T)&=V^mathbbQleft(int_0^Tsigma e^r(T-s) dW^mathbbQ_sright)
\[9pt]
&=E^mathbbQleft(left(int_0^Tsigma e^r(T-s) dW^mathbbQ_sright)^2right)-underbraceE^mathbbQleft(int_0^Tsigma e^r(T-s) dW^mathbbQ_sright)_=int_0^Tsigma e^r(T-s) E^mathbbQ(dW^mathbbQ_s)=0^2
\[-9pt]
&=E^mathbbQleft(int_0^Tsigma^2 e^2r(T-s) dsright)
endalign$$

The remaining integral is deterministic, thus:
$$V(S_T)=sigma^2left[-frace^2r(T-s)2rright]_s=0^s=T=sigma^2left(frace^2rT-12rright)$$
Note that your result is correct up to a minus sign. This is probably because the Bachelier dynamics for the stock price are also known as an Ornstein–Uhlenbeck process, which is normally defined with a minus sign in the drift, i.e.:
$$dS_t = colorred-r S_t dt + sigma W^mathbbQ_t$$
in which case the volatility is given by the expression in your original post.






share|improve this answer









$endgroup$















    Your Answer








    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%2f46301%2fproblem-at-deriving-bachelier-formula-with-interest-rates%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









    4












    $begingroup$

    As explained by @byouness, using Itô's Isometry, we get:
    $$beginalign
    V(S_T)&=V^mathbbQleft(int_0^Tsigma e^r(T-s) dW^mathbbQ_sright)
    \[9pt]
    &=E^mathbbQleft(left(int_0^Tsigma e^r(T-s) dW^mathbbQ_sright)^2right)-underbraceE^mathbbQleft(int_0^Tsigma e^r(T-s) dW^mathbbQ_sright)_=int_0^Tsigma e^r(T-s) E^mathbbQ(dW^mathbbQ_s)=0^2
    \[-9pt]
    &=E^mathbbQleft(int_0^Tsigma^2 e^2r(T-s) dsright)
    endalign$$

    The remaining integral is deterministic, thus:
    $$V(S_T)=sigma^2left[-frace^2r(T-s)2rright]_s=0^s=T=sigma^2left(frace^2rT-12rright)$$
    Note that your result is correct up to a minus sign. This is probably because the Bachelier dynamics for the stock price are also known as an Ornstein–Uhlenbeck process, which is normally defined with a minus sign in the drift, i.e.:
    $$dS_t = colorred-r S_t dt + sigma W^mathbbQ_t$$
    in which case the volatility is given by the expression in your original post.






    share|improve this answer









    $endgroup$

















      4












      $begingroup$

      As explained by @byouness, using Itô's Isometry, we get:
      $$beginalign
      V(S_T)&=V^mathbbQleft(int_0^Tsigma e^r(T-s) dW^mathbbQ_sright)
      \[9pt]
      &=E^mathbbQleft(left(int_0^Tsigma e^r(T-s) dW^mathbbQ_sright)^2right)-underbraceE^mathbbQleft(int_0^Tsigma e^r(T-s) dW^mathbbQ_sright)_=int_0^Tsigma e^r(T-s) E^mathbbQ(dW^mathbbQ_s)=0^2
      \[-9pt]
      &=E^mathbbQleft(int_0^Tsigma^2 e^2r(T-s) dsright)
      endalign$$

      The remaining integral is deterministic, thus:
      $$V(S_T)=sigma^2left[-frace^2r(T-s)2rright]_s=0^s=T=sigma^2left(frace^2rT-12rright)$$
      Note that your result is correct up to a minus sign. This is probably because the Bachelier dynamics for the stock price are also known as an Ornstein–Uhlenbeck process, which is normally defined with a minus sign in the drift, i.e.:
      $$dS_t = colorred-r S_t dt + sigma W^mathbbQ_t$$
      in which case the volatility is given by the expression in your original post.






      share|improve this answer









      $endgroup$















        4












        4








        4





        $begingroup$

        As explained by @byouness, using Itô's Isometry, we get:
        $$beginalign
        V(S_T)&=V^mathbbQleft(int_0^Tsigma e^r(T-s) dW^mathbbQ_sright)
        \[9pt]
        &=E^mathbbQleft(left(int_0^Tsigma e^r(T-s) dW^mathbbQ_sright)^2right)-underbraceE^mathbbQleft(int_0^Tsigma e^r(T-s) dW^mathbbQ_sright)_=int_0^Tsigma e^r(T-s) E^mathbbQ(dW^mathbbQ_s)=0^2
        \[-9pt]
        &=E^mathbbQleft(int_0^Tsigma^2 e^2r(T-s) dsright)
        endalign$$

        The remaining integral is deterministic, thus:
        $$V(S_T)=sigma^2left[-frace^2r(T-s)2rright]_s=0^s=T=sigma^2left(frace^2rT-12rright)$$
        Note that your result is correct up to a minus sign. This is probably because the Bachelier dynamics for the stock price are also known as an Ornstein–Uhlenbeck process, which is normally defined with a minus sign in the drift, i.e.:
        $$dS_t = colorred-r S_t dt + sigma W^mathbbQ_t$$
        in which case the volatility is given by the expression in your original post.






        share|improve this answer









        $endgroup$



        As explained by @byouness, using Itô's Isometry, we get:
        $$beginalign
        V(S_T)&=V^mathbbQleft(int_0^Tsigma e^r(T-s) dW^mathbbQ_sright)
        \[9pt]
        &=E^mathbbQleft(left(int_0^Tsigma e^r(T-s) dW^mathbbQ_sright)^2right)-underbraceE^mathbbQleft(int_0^Tsigma e^r(T-s) dW^mathbbQ_sright)_=int_0^Tsigma e^r(T-s) E^mathbbQ(dW^mathbbQ_s)=0^2
        \[-9pt]
        &=E^mathbbQleft(int_0^Tsigma^2 e^2r(T-s) dsright)
        endalign$$

        The remaining integral is deterministic, thus:
        $$V(S_T)=sigma^2left[-frace^2r(T-s)2rright]_s=0^s=T=sigma^2left(frace^2rT-12rright)$$
        Note that your result is correct up to a minus sign. This is probably because the Bachelier dynamics for the stock price are also known as an Ornstein–Uhlenbeck process, which is normally defined with a minus sign in the drift, i.e.:
        $$dS_t = colorred-r S_t dt + sigma W^mathbbQ_t$$
        in which case the volatility is given by the expression in your original post.







        share|improve this answer












        share|improve this answer



        share|improve this answer










        answered Jun 26 at 9:11









        Daneel OlivawDaneel Olivaw

        3,3431 gold badge8 silver badges31 bronze badges




        3,3431 gold badge8 silver badges31 bronze badges



























            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%2f46301%2fproblem-at-deriving-bachelier-formula-with-interest-rates%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

            Get product attribute by attribute group code in magento 2get product attribute by product attribute group in magento 2Magento 2 Log Bundle Product Data in List Page?How to get all product attribute of a attribute group of Default attribute set?Magento 2.1 Create a filter in the product grid by new attributeMagento 2 : Get Product Attribute values By GroupMagento 2 How to get all existing values for one attributeMagento 2 get custom attribute of a single product inside a pluginMagento 2.3 How to get all the Multi Source Inventory (MSI) locations collection in custom module?Magento2: how to develop rest API to get new productsGet product attribute by attribute group code ( [attribute_group_code] ) in magento 2

            Category:9 (number) SubcategoriesMedia in category "9 (number)"Navigation menuUpload mediaGND ID: 4485639-8Library of Congress authority ID: sh85091979ReasonatorScholiaStatistics

            Magento 2.3: How do i solve this, Not registered handle, on custom form?How can i rewrite TierPrice Block in Magento2magento 2 captcha not rendering if I override layout xmlmain.CRITICAL: Plugin class doesn't existMagento 2 : Problem while adding custom button order view page?Magento 2.2.5: Overriding Admin Controller sales/orderMagento 2.2.5: Add, Update and Delete existing products Custom OptionsMagento 2.3 : File Upload issue in UI Component FormMagento2 Not registered handleHow to configured Form Builder Js in my custom magento 2.3.0 module?Magento 2.3. How to create image upload field in an admin form