probability measure of Random Variable on probability space












0














A random variable is a function that transform a probability space to another space is built up on real number



i.e ($Omega,mathcal F,P)to(Bbb R,mathcal B,P_X$)



and a random variable is call measurable if $forall B in mathcal B$ $X^{-1}(B)inmathcal F$



How do we guarantee that$P(A)$ $forall Ain mathcal F $
is equal to $P_X(B)forall Bin mathcal B$



or How we show that $int _AdP=int _BdP_X$
where $A=$ $X^{-1}(B)$ $forall Bin mathcal B$



I know this maybe intuitive but I want have a strict mathematics proof to show this two things is equal










share|cite|improve this question



























    0














    A random variable is a function that transform a probability space to another space is built up on real number



    i.e ($Omega,mathcal F,P)to(Bbb R,mathcal B,P_X$)



    and a random variable is call measurable if $forall B in mathcal B$ $X^{-1}(B)inmathcal F$



    How do we guarantee that$P(A)$ $forall Ain mathcal F $
    is equal to $P_X(B)forall Bin mathcal B$



    or How we show that $int _AdP=int _BdP_X$
    where $A=$ $X^{-1}(B)$ $forall Bin mathcal B$



    I know this maybe intuitive but I want have a strict mathematics proof to show this two things is equal










    share|cite|improve this question

























      0












      0








      0







      A random variable is a function that transform a probability space to another space is built up on real number



      i.e ($Omega,mathcal F,P)to(Bbb R,mathcal B,P_X$)



      and a random variable is call measurable if $forall B in mathcal B$ $X^{-1}(B)inmathcal F$



      How do we guarantee that$P(A)$ $forall Ain mathcal F $
      is equal to $P_X(B)forall Bin mathcal B$



      or How we show that $int _AdP=int _BdP_X$
      where $A=$ $X^{-1}(B)$ $forall Bin mathcal B$



      I know this maybe intuitive but I want have a strict mathematics proof to show this two things is equal










      share|cite|improve this question













      A random variable is a function that transform a probability space to another space is built up on real number



      i.e ($Omega,mathcal F,P)to(Bbb R,mathcal B,P_X$)



      and a random variable is call measurable if $forall B in mathcal B$ $X^{-1}(B)inmathcal F$



      How do we guarantee that$P(A)$ $forall Ain mathcal F $
      is equal to $P_X(B)forall Bin mathcal B$



      or How we show that $int _AdP=int _BdP_X$
      where $A=$ $X^{-1}(B)$ $forall Bin mathcal B$



      I know this maybe intuitive but I want have a strict mathematics proof to show this two things is equal







      probability probability-theory measure-theory






      share|cite|improve this question













      share|cite|improve this question











      share|cite|improve this question




      share|cite|improve this question










      asked Nov 22 '18 at 1:10









      Vergil ChanVergil Chan

      334




      334






















          1 Answer
          1






          active

          oldest

          votes


















          2














          That's because the construction of the probability measure $P^{X}$.



          You can see that $forall Bin mathcal{B}, hspace{0.3 cm}$ $P^{X}(B):=P(X^{-1}(B))$ is indeed a probability measure in the space $(mathbb{R},mathcal{B})$. (Check that it satisfies the axioms of probability)



          Therefore,
          $ forall Bin mathcal{B} hspace{0.2 cm}$ if we define $A=X^{-1}(B)in mathcal{F}$



          we have that
          $P^{X}(B)=P(X^{-1}(B))=P(A)$






          share|cite|improve this answer























            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%2f3008616%2fprobability-measure-of-random-variable-on-probability-space%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














            That's because the construction of the probability measure $P^{X}$.



            You can see that $forall Bin mathcal{B}, hspace{0.3 cm}$ $P^{X}(B):=P(X^{-1}(B))$ is indeed a probability measure in the space $(mathbb{R},mathcal{B})$. (Check that it satisfies the axioms of probability)



            Therefore,
            $ forall Bin mathcal{B} hspace{0.2 cm}$ if we define $A=X^{-1}(B)in mathcal{F}$



            we have that
            $P^{X}(B)=P(X^{-1}(B))=P(A)$






            share|cite|improve this answer




























              2














              That's because the construction of the probability measure $P^{X}$.



              You can see that $forall Bin mathcal{B}, hspace{0.3 cm}$ $P^{X}(B):=P(X^{-1}(B))$ is indeed a probability measure in the space $(mathbb{R},mathcal{B})$. (Check that it satisfies the axioms of probability)



              Therefore,
              $ forall Bin mathcal{B} hspace{0.2 cm}$ if we define $A=X^{-1}(B)in mathcal{F}$



              we have that
              $P^{X}(B)=P(X^{-1}(B))=P(A)$






              share|cite|improve this answer


























                2












                2








                2






                That's because the construction of the probability measure $P^{X}$.



                You can see that $forall Bin mathcal{B}, hspace{0.3 cm}$ $P^{X}(B):=P(X^{-1}(B))$ is indeed a probability measure in the space $(mathbb{R},mathcal{B})$. (Check that it satisfies the axioms of probability)



                Therefore,
                $ forall Bin mathcal{B} hspace{0.2 cm}$ if we define $A=X^{-1}(B)in mathcal{F}$



                we have that
                $P^{X}(B)=P(X^{-1}(B))=P(A)$






                share|cite|improve this answer














                That's because the construction of the probability measure $P^{X}$.



                You can see that $forall Bin mathcal{B}, hspace{0.3 cm}$ $P^{X}(B):=P(X^{-1}(B))$ is indeed a probability measure in the space $(mathbb{R},mathcal{B})$. (Check that it satisfies the axioms of probability)



                Therefore,
                $ forall Bin mathcal{B} hspace{0.2 cm}$ if we define $A=X^{-1}(B)in mathcal{F}$



                we have that
                $P^{X}(B)=P(X^{-1}(B))=P(A)$







                share|cite|improve this answer














                share|cite|improve this answer



                share|cite|improve this answer








                edited Nov 22 '18 at 2:41









                Graham Kemp

                84.7k43378




                84.7k43378










                answered Nov 22 '18 at 1:45









                GuilleAlAlGuilleAlAl

                212




                212






























                    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.





                    Some of your past answers have not been well-received, and you're in danger of being blocked from answering.


                    Please pay close attention to the following guidance:


                    • 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.


                    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%2f3008616%2fprobability-measure-of-random-variable-on-probability-space%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

                    Can a sorcerer learn a 5th-level spell early by creating spell slots using the Font of Magic feature?

                    ts Property 'filter' does not exist on type '{}'

                    mat-slide-toggle shouldn't change it's state when I click cancel in confirmation window