Measure of a Brownian motion = normal distribution?How to simulate stock prices with a Geometric Brownian...

What are "industrial chops"?

Can I become debt free or should I file bankruptcy ? How to manage my debt and finances?

Why is the copy constructor called twice in this code snippet?

How can I deliver in-universe written lore to players without it being dry exposition?

Is it a fallacy if someone claims they need an explanation for every word of your argument to the point where they don't understand common terms?

How to count the characters of jar files by wc

Am I a Rude Number?

Why has the mole been redefined for 2019?

What is 6÷2×(1+2) =?

Why zero tolerance on nudity in space?

Avoiding morning and evening handshakes

Could a phylactery of a lich be a mirror or does it have to be a box?

How long is the D&D Starter Set campaign?

awk + sum all numbers

Incorporating research and background: How much is too much?

The weather forecast

A starship is travelling at 0.9c and collides with a small rock. Will it leave a clean hole through, or will more happen?

Roman Numerals equation 1

CREATE ASSEMBLY System.DirectoryServices.AccountManagement.dll without enabling TRUSTWORTHY

How to avoid being sexist when trying to employ someone to function in a very sexist environment?

Why did the villain in the first Men in Black movie care about Earth's Cockroaches?

Can we use the stored gravitational potential energy of a building to produce power?

How can animals be objects of ethics without being subjects as well?

Eww, those bytes are gross



Measure of a Brownian motion = normal distribution?


How to simulate stock prices with a Geometric Brownian Motion?Modelling driftless stock price with geometric Brownian motionHow to compute the conditional expected value of a geometric brownian motion?Confidence Intervals of Stock Following a Geometric Brownian MotionThe Distribution of Future Stock PriceSimulations of (standard, one-dimensional) Brownian motionOn the construction of a Brownian motion from a Gaussian processSimulate drifted geometric brownian motion under new measureDo we have a Brownian motionHow to prove we have a $mathbb{Q}$-Brownian motion?













2












$begingroup$


Consider some model where the process increments are normally distributed, e.g. Vasicek:
$$dr(t) = left(theta - ar(t)right)dt + sigma dW(t).$$



We usually say that $W(t)$ is a Brownian motion under a measure $mathbb P$. $W(t)$ is a Brownian motion if, among other conditions, $W(t) sim N(0, t)$ given $W(0)=0$. Does it mean that the measure $mathbb P$ is actually a normal distribution, i.e.
$$mathbb Pleft(frac{W(t)}{sqrt t} in [a ,b]right) = Phi(b) - Phi(a)$$ where $Phi(cdot)$ denotes the CDF of a standard normal random variable?










share|improve this question











$endgroup$












  • $begingroup$
    The equation you wrote is correct. But it is only one example of the properties of the measure P. The measure P is more general than this and cannot be said "to be a normal distribution", but the normal distribution does come up in describing the measure. The measure applies to a stochastic procees, the normal distribution applies to a random variable, so they cannot be identical.
    $endgroup$
    – noob2
    5 hours ago


















2












$begingroup$


Consider some model where the process increments are normally distributed, e.g. Vasicek:
$$dr(t) = left(theta - ar(t)right)dt + sigma dW(t).$$



We usually say that $W(t)$ is a Brownian motion under a measure $mathbb P$. $W(t)$ is a Brownian motion if, among other conditions, $W(t) sim N(0, t)$ given $W(0)=0$. Does it mean that the measure $mathbb P$ is actually a normal distribution, i.e.
$$mathbb Pleft(frac{W(t)}{sqrt t} in [a ,b]right) = Phi(b) - Phi(a)$$ where $Phi(cdot)$ denotes the CDF of a standard normal random variable?










share|improve this question











$endgroup$












  • $begingroup$
    The equation you wrote is correct. But it is only one example of the properties of the measure P. The measure P is more general than this and cannot be said "to be a normal distribution", but the normal distribution does come up in describing the measure. The measure applies to a stochastic procees, the normal distribution applies to a random variable, so they cannot be identical.
    $endgroup$
    – noob2
    5 hours ago
















2












2








2





$begingroup$


Consider some model where the process increments are normally distributed, e.g. Vasicek:
$$dr(t) = left(theta - ar(t)right)dt + sigma dW(t).$$



We usually say that $W(t)$ is a Brownian motion under a measure $mathbb P$. $W(t)$ is a Brownian motion if, among other conditions, $W(t) sim N(0, t)$ given $W(0)=0$. Does it mean that the measure $mathbb P$ is actually a normal distribution, i.e.
$$mathbb Pleft(frac{W(t)}{sqrt t} in [a ,b]right) = Phi(b) - Phi(a)$$ where $Phi(cdot)$ denotes the CDF of a standard normal random variable?










share|improve this question











$endgroup$




Consider some model where the process increments are normally distributed, e.g. Vasicek:
$$dr(t) = left(theta - ar(t)right)dt + sigma dW(t).$$



We usually say that $W(t)$ is a Brownian motion under a measure $mathbb P$. $W(t)$ is a Brownian motion if, among other conditions, $W(t) sim N(0, t)$ given $W(0)=0$. Does it mean that the measure $mathbb P$ is actually a normal distribution, i.e.
$$mathbb Pleft(frac{W(t)}{sqrt t} in [a ,b]right) = Phi(b) - Phi(a)$$ where $Phi(cdot)$ denotes the CDF of a standard normal random variable?







brownian-motion risk-neutral-measure normal-distribution self-study






share|improve this question















share|improve this question













share|improve this question




share|improve this question








edited 5 hours ago







tosik

















asked 5 hours ago









tosiktosik

26927




26927












  • $begingroup$
    The equation you wrote is correct. But it is only one example of the properties of the measure P. The measure P is more general than this and cannot be said "to be a normal distribution", but the normal distribution does come up in describing the measure. The measure applies to a stochastic procees, the normal distribution applies to a random variable, so they cannot be identical.
    $endgroup$
    – noob2
    5 hours ago




















  • $begingroup$
    The equation you wrote is correct. But it is only one example of the properties of the measure P. The measure P is more general than this and cannot be said "to be a normal distribution", but the normal distribution does come up in describing the measure. The measure applies to a stochastic procees, the normal distribution applies to a random variable, so they cannot be identical.
    $endgroup$
    – noob2
    5 hours ago


















$begingroup$
The equation you wrote is correct. But it is only one example of the properties of the measure P. The measure P is more general than this and cannot be said "to be a normal distribution", but the normal distribution does come up in describing the measure. The measure applies to a stochastic procees, the normal distribution applies to a random variable, so they cannot be identical.
$endgroup$
– noob2
5 hours ago






$begingroup$
The equation you wrote is correct. But it is only one example of the properties of the measure P. The measure P is more general than this and cannot be said "to be a normal distribution", but the normal distribution does come up in describing the measure. The measure applies to a stochastic procees, the normal distribution applies to a random variable, so they cannot be identical.
$endgroup$
– noob2
5 hours ago












1 Answer
1






active

oldest

votes


















4












$begingroup$

I am not allowed post a comment, so it goes here.




  1. It is correct that
    $$
    mathbf{P}(t^{-1/2}W(t) in[a,b])=Φ(b)−Φ(a), forall tin(0,infty)
    $$

    due to the stationary increments property of the Wiener process and the fact that you normalized the random variable by dividing by its standard deviation.


  2. $mathbf{P}$ is a probability measure on an abstract space, not a random variable. Hence, you probably mean that $W(t)$ is normally distributed under $mathbf{P}$, NOT $mathbf{P}$ is normally distributed. People tend to mention the probability measure, for if you change it the process will no longer be Gaussian.





share










New contributor




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






$endgroup$









  • 2




    $begingroup$
    Welcome to Quant SE. No need for comments :) This is (along with the rest of your answers) acceptable as an answer to the question.
    $endgroup$
    – Sanjay
    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%2f44339%2fmeasure-of-a-brownian-motion-normal-distribution%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












$begingroup$

I am not allowed post a comment, so it goes here.




  1. It is correct that
    $$
    mathbf{P}(t^{-1/2}W(t) in[a,b])=Φ(b)−Φ(a), forall tin(0,infty)
    $$

    due to the stationary increments property of the Wiener process and the fact that you normalized the random variable by dividing by its standard deviation.


  2. $mathbf{P}$ is a probability measure on an abstract space, not a random variable. Hence, you probably mean that $W(t)$ is normally distributed under $mathbf{P}$, NOT $mathbf{P}$ is normally distributed. People tend to mention the probability measure, for if you change it the process will no longer be Gaussian.





share










New contributor




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






$endgroup$









  • 2




    $begingroup$
    Welcome to Quant SE. No need for comments :) This is (along with the rest of your answers) acceptable as an answer to the question.
    $endgroup$
    – Sanjay
    4 hours ago
















4












$begingroup$

I am not allowed post a comment, so it goes here.




  1. It is correct that
    $$
    mathbf{P}(t^{-1/2}W(t) in[a,b])=Φ(b)−Φ(a), forall tin(0,infty)
    $$

    due to the stationary increments property of the Wiener process and the fact that you normalized the random variable by dividing by its standard deviation.


  2. $mathbf{P}$ is a probability measure on an abstract space, not a random variable. Hence, you probably mean that $W(t)$ is normally distributed under $mathbf{P}$, NOT $mathbf{P}$ is normally distributed. People tend to mention the probability measure, for if you change it the process will no longer be Gaussian.





share










New contributor




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






$endgroup$









  • 2




    $begingroup$
    Welcome to Quant SE. No need for comments :) This is (along with the rest of your answers) acceptable as an answer to the question.
    $endgroup$
    – Sanjay
    4 hours ago














4












4








4





$begingroup$

I am not allowed post a comment, so it goes here.




  1. It is correct that
    $$
    mathbf{P}(t^{-1/2}W(t) in[a,b])=Φ(b)−Φ(a), forall tin(0,infty)
    $$

    due to the stationary increments property of the Wiener process and the fact that you normalized the random variable by dividing by its standard deviation.


  2. $mathbf{P}$ is a probability measure on an abstract space, not a random variable. Hence, you probably mean that $W(t)$ is normally distributed under $mathbf{P}$, NOT $mathbf{P}$ is normally distributed. People tend to mention the probability measure, for if you change it the process will no longer be Gaussian.





share










New contributor




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






$endgroup$



I am not allowed post a comment, so it goes here.




  1. It is correct that
    $$
    mathbf{P}(t^{-1/2}W(t) in[a,b])=Φ(b)−Φ(a), forall tin(0,infty)
    $$

    due to the stationary increments property of the Wiener process and the fact that you normalized the random variable by dividing by its standard deviation.


  2. $mathbf{P}$ is a probability measure on an abstract space, not a random variable. Hence, you probably mean that $W(t)$ is normally distributed under $mathbf{P}$, NOT $mathbf{P}$ is normally distributed. People tend to mention the probability measure, for if you change it the process will no longer be Gaussian.






share










New contributor




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








share


share








edited 1 hour ago





















New contributor




phantagarow 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









phantagarowphantagarow

514




514




New contributor




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





New contributor





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






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








  • 2




    $begingroup$
    Welcome to Quant SE. No need for comments :) This is (along with the rest of your answers) acceptable as an answer to the question.
    $endgroup$
    – Sanjay
    4 hours ago














  • 2




    $begingroup$
    Welcome to Quant SE. No need for comments :) This is (along with the rest of your answers) acceptable as an answer to the question.
    $endgroup$
    – Sanjay
    4 hours ago








2




2




$begingroup$
Welcome to Quant SE. No need for comments :) This is (along with the rest of your answers) acceptable as an answer to the question.
$endgroup$
– Sanjay
4 hours ago




$begingroup$
Welcome to Quant SE. No need for comments :) This is (along with the rest of your answers) acceptable as an answer to the question.
$endgroup$
– Sanjay
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%2f44339%2fmeasure-of-a-brownian-motion-normal-distribution%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

Benedict Cumberbatch Contingut Inicis Debut professional Premis Filmografia bàsica Premis i...

Monticle de plataforma Contingut Est de Nord Amèrica Interpretacions Altres cultures Vegeu...

Escacs Janus Enllaços externs Menú de navegacióEscacs JanusJanusschachBrainKing.comChessV