Fisher information of normal distribution with unknown mean and variance?Convergence rate of empirical Fisher information matrixFisher Information and minimum variance estimatorsSufficient Statistics, MLE and Unbiased Estimators of Uniform Type DistributionCalculating a Fisher expected informationFisher information matrix of MLE'sFor a Fisher Information, $mathcalI(theta)$, why does $mathcalI(theta) = nmathcalI_1(theta)$ not hold for multiple dimensions?Fisher's information of normal distributionFisher information comparisonComparing Fisher Information of sample to that of statisticCalculating Fisher Information for Bernoulli rv

Examples of a statistic that is not independent of sample's distribution?

Am I not good enough for you?

Is "history" a male-biased word ("his+story")?

'The literal of type int is out of range' con número enteros pequeños (2 dígitos)

How many characters using PHB rules does it take to be able to have access to any PHB spell at the start of an adventuring day?

Are babies of evil humanoid species inherently evil?

Should I tell my boss the work he did was worthless

Counting all the hearts

Signed and unsigned numbers

Do items de-spawn in Diablo?

Are there historical instances of the capital of a colonising country being temporarily or permanently shifted to one of its colonies?

UART pins to unpowered MCU?

How is the wildcard * interpreted as a command?

Database Backup for data and log files

Declaring and defining template, and specialising them

Accepted offer letter, position changed

NASA's RS-25 Engines shut down time

How to write ı (i without dot) character in pgf-pie

How did Alan Turing break the enigma code using the hint given by the lady in the bar?

PTIJ: wiping amalek’s memory?

In the late 1940’s to early 1950’s what technology was available that could melt a LOT of ice?

Doesn't allowing a user mode program to access kernel space memory and execute the IN and OUT instructions defeat the purpose of having CPU modes?

If I receive an SOS signal, what is the proper response?

What are actual Tesla M60 models used by AWS?



Fisher information of normal distribution with unknown mean and variance?


Convergence rate of empirical Fisher information matrixFisher Information and minimum variance estimatorsSufficient Statistics, MLE and Unbiased Estimators of Uniform Type DistributionCalculating a Fisher expected informationFisher information matrix of MLE'sFor a Fisher Information, $mathcalI(theta)$, why does $mathcalI(theta) = nmathcalI_1(theta)$ not hold for multiple dimensions?Fisher's information of normal distributionFisher information comparisonComparing Fisher Information of sample to that of statisticCalculating Fisher Information for Bernoulli rv













0












$begingroup$


I am asked to find the fisher information contained in $X_1 sim N(theta_1, theta_2)$ (ie: two unknown parameters, only one observation). How would I find the Fisher information here?



I know that with a sample $X_1,X_2,ldots,X_n $~$N(mu,sigma^2)$ and $sigma^2=1$, Fisher's information is given by :
$$
-E(fracd^2dmu^2 ln f(x))=1/sigma^2.
$$

Though this is the case with one paramter and I am not sure how it would map on to the case with two parameters. I imagine there is some use of a Hessian but I am not sure what to do.










share|cite|improve this question











$endgroup$
















    0












    $begingroup$


    I am asked to find the fisher information contained in $X_1 sim N(theta_1, theta_2)$ (ie: two unknown parameters, only one observation). How would I find the Fisher information here?



    I know that with a sample $X_1,X_2,ldots,X_n $~$N(mu,sigma^2)$ and $sigma^2=1$, Fisher's information is given by :
    $$
    -E(fracd^2dmu^2 ln f(x))=1/sigma^2.
    $$

    Though this is the case with one paramter and I am not sure how it would map on to the case with two parameters. I imagine there is some use of a Hessian but I am not sure what to do.










    share|cite|improve this question











    $endgroup$














      0












      0








      0





      $begingroup$


      I am asked to find the fisher information contained in $X_1 sim N(theta_1, theta_2)$ (ie: two unknown parameters, only one observation). How would I find the Fisher information here?



      I know that with a sample $X_1,X_2,ldots,X_n $~$N(mu,sigma^2)$ and $sigma^2=1$, Fisher's information is given by :
      $$
      -E(fracd^2dmu^2 ln f(x))=1/sigma^2.
      $$

      Though this is the case with one paramter and I am not sure how it would map on to the case with two parameters. I imagine there is some use of a Hessian but I am not sure what to do.










      share|cite|improve this question











      $endgroup$




      I am asked to find the fisher information contained in $X_1 sim N(theta_1, theta_2)$ (ie: two unknown parameters, only one observation). How would I find the Fisher information here?



      I know that with a sample $X_1,X_2,ldots,X_n $~$N(mu,sigma^2)$ and $sigma^2=1$, Fisher's information is given by :
      $$
      -E(fracd^2dmu^2 ln f(x))=1/sigma^2.
      $$

      Though this is the case with one paramter and I am not sure how it would map on to the case with two parameters. I imagine there is some use of a Hessian but I am not sure what to do.







      probability statistics expected-value fisher-information






      share|cite|improve this question















      share|cite|improve this question













      share|cite|improve this question




      share|cite|improve this question








      edited 2 days ago







      j doe

















      asked 2 days ago









      j doej doe

      11




      11




















          1 Answer
          1






          active

          oldest

          votes


















          0












          $begingroup$

          It will be the expected value of the Hessian matrix of $ln f(x;mu, sigma^2)$. Specifically for the normal distribution, you can check that it will a diagonal matrix. The $mathcalI_11$ you have already calculated. For the second diagonal term
          $$
          ln f(x;mu, sigma)=-frac12ln(2 sigma^2)+frac12sigma^2(x-mu)^2,
          $$

          $$
          l'_sigma^2 = - frac12sigma^2 - frac12sigma^4(x-mu)^2,
          $$

          hence
          $$
          mathcalI_22= -mathbbE[l''_sigma^2]
          =
          - mathbbE [ frac12sigma^4 - frac1sigma^6(x-mu)^2]
          =
          -frac12sigma^4 + frac2sigma^4 = frac12sigma^4 .
          $$

          And for the non-diagonal terms
          $$
          mathcalI_22= -mathbbE[l''_sigma^2,mu] = - mathbbEfrac2(x-mu)2sigma^4 = 0.
          $$






          share|cite|improve this answer











          $endgroup$












          • $begingroup$
            Can you say a bit more about that? What would be the entries in the Hessian?
            $endgroup$
            – j doe
            2 days ago










          • $begingroup$
            If you let $l$ be the log-likelihood function and write $vequiv sigma^2$ for simplicity, the Hessian of the log-likelihood function will be equal to $$colorbluebeginbmatrixfracpartial^2 lpartial mu^2 & fracpartial^2 lpartial mu partial v \ fracpartial^2 lpartial mu partial v & fracpartial^2 lpartial v^2endbmatrix.$$Note that the Hessian is a symmetric matrix, so once you calculate the top right entry, you can copy it into the bottom left entry.
            $endgroup$
            – Minus One-Twelfth
            2 days ago











          • $begingroup$
            @jdoe pls see the edited answer
            $endgroup$
            – V. Vancak
            yesterday










          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%2f3141691%2ffisher-information-of-normal-distribution-with-unknown-mean-and-variance%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 will be the expected value of the Hessian matrix of $ln f(x;mu, sigma^2)$. Specifically for the normal distribution, you can check that it will a diagonal matrix. The $mathcalI_11$ you have already calculated. For the second diagonal term
          $$
          ln f(x;mu, sigma)=-frac12ln(2 sigma^2)+frac12sigma^2(x-mu)^2,
          $$

          $$
          l'_sigma^2 = - frac12sigma^2 - frac12sigma^4(x-mu)^2,
          $$

          hence
          $$
          mathcalI_22= -mathbbE[l''_sigma^2]
          =
          - mathbbE [ frac12sigma^4 - frac1sigma^6(x-mu)^2]
          =
          -frac12sigma^4 + frac2sigma^4 = frac12sigma^4 .
          $$

          And for the non-diagonal terms
          $$
          mathcalI_22= -mathbbE[l''_sigma^2,mu] = - mathbbEfrac2(x-mu)2sigma^4 = 0.
          $$






          share|cite|improve this answer











          $endgroup$












          • $begingroup$
            Can you say a bit more about that? What would be the entries in the Hessian?
            $endgroup$
            – j doe
            2 days ago










          • $begingroup$
            If you let $l$ be the log-likelihood function and write $vequiv sigma^2$ for simplicity, the Hessian of the log-likelihood function will be equal to $$colorbluebeginbmatrixfracpartial^2 lpartial mu^2 & fracpartial^2 lpartial mu partial v \ fracpartial^2 lpartial mu partial v & fracpartial^2 lpartial v^2endbmatrix.$$Note that the Hessian is a symmetric matrix, so once you calculate the top right entry, you can copy it into the bottom left entry.
            $endgroup$
            – Minus One-Twelfth
            2 days ago











          • $begingroup$
            @jdoe pls see the edited answer
            $endgroup$
            – V. Vancak
            yesterday















          0












          $begingroup$

          It will be the expected value of the Hessian matrix of $ln f(x;mu, sigma^2)$. Specifically for the normal distribution, you can check that it will a diagonal matrix. The $mathcalI_11$ you have already calculated. For the second diagonal term
          $$
          ln f(x;mu, sigma)=-frac12ln(2 sigma^2)+frac12sigma^2(x-mu)^2,
          $$

          $$
          l'_sigma^2 = - frac12sigma^2 - frac12sigma^4(x-mu)^2,
          $$

          hence
          $$
          mathcalI_22= -mathbbE[l''_sigma^2]
          =
          - mathbbE [ frac12sigma^4 - frac1sigma^6(x-mu)^2]
          =
          -frac12sigma^4 + frac2sigma^4 = frac12sigma^4 .
          $$

          And for the non-diagonal terms
          $$
          mathcalI_22= -mathbbE[l''_sigma^2,mu] = - mathbbEfrac2(x-mu)2sigma^4 = 0.
          $$






          share|cite|improve this answer











          $endgroup$












          • $begingroup$
            Can you say a bit more about that? What would be the entries in the Hessian?
            $endgroup$
            – j doe
            2 days ago










          • $begingroup$
            If you let $l$ be the log-likelihood function and write $vequiv sigma^2$ for simplicity, the Hessian of the log-likelihood function will be equal to $$colorbluebeginbmatrixfracpartial^2 lpartial mu^2 & fracpartial^2 lpartial mu partial v \ fracpartial^2 lpartial mu partial v & fracpartial^2 lpartial v^2endbmatrix.$$Note that the Hessian is a symmetric matrix, so once you calculate the top right entry, you can copy it into the bottom left entry.
            $endgroup$
            – Minus One-Twelfth
            2 days ago











          • $begingroup$
            @jdoe pls see the edited answer
            $endgroup$
            – V. Vancak
            yesterday













          0












          0








          0





          $begingroup$

          It will be the expected value of the Hessian matrix of $ln f(x;mu, sigma^2)$. Specifically for the normal distribution, you can check that it will a diagonal matrix. The $mathcalI_11$ you have already calculated. For the second diagonal term
          $$
          ln f(x;mu, sigma)=-frac12ln(2 sigma^2)+frac12sigma^2(x-mu)^2,
          $$

          $$
          l'_sigma^2 = - frac12sigma^2 - frac12sigma^4(x-mu)^2,
          $$

          hence
          $$
          mathcalI_22= -mathbbE[l''_sigma^2]
          =
          - mathbbE [ frac12sigma^4 - frac1sigma^6(x-mu)^2]
          =
          -frac12sigma^4 + frac2sigma^4 = frac12sigma^4 .
          $$

          And for the non-diagonal terms
          $$
          mathcalI_22= -mathbbE[l''_sigma^2,mu] = - mathbbEfrac2(x-mu)2sigma^4 = 0.
          $$






          share|cite|improve this answer











          $endgroup$



          It will be the expected value of the Hessian matrix of $ln f(x;mu, sigma^2)$. Specifically for the normal distribution, you can check that it will a diagonal matrix. The $mathcalI_11$ you have already calculated. For the second diagonal term
          $$
          ln f(x;mu, sigma)=-frac12ln(2 sigma^2)+frac12sigma^2(x-mu)^2,
          $$

          $$
          l'_sigma^2 = - frac12sigma^2 - frac12sigma^4(x-mu)^2,
          $$

          hence
          $$
          mathcalI_22= -mathbbE[l''_sigma^2]
          =
          - mathbbE [ frac12sigma^4 - frac1sigma^6(x-mu)^2]
          =
          -frac12sigma^4 + frac2sigma^4 = frac12sigma^4 .
          $$

          And for the non-diagonal terms
          $$
          mathcalI_22= -mathbbE[l''_sigma^2,mu] = - mathbbEfrac2(x-mu)2sigma^4 = 0.
          $$







          share|cite|improve this answer














          share|cite|improve this answer



          share|cite|improve this answer








          edited yesterday

























          answered 2 days ago









          V. VancakV. Vancak

          11.3k3926




          11.3k3926











          • $begingroup$
            Can you say a bit more about that? What would be the entries in the Hessian?
            $endgroup$
            – j doe
            2 days ago










          • $begingroup$
            If you let $l$ be the log-likelihood function and write $vequiv sigma^2$ for simplicity, the Hessian of the log-likelihood function will be equal to $$colorbluebeginbmatrixfracpartial^2 lpartial mu^2 & fracpartial^2 lpartial mu partial v \ fracpartial^2 lpartial mu partial v & fracpartial^2 lpartial v^2endbmatrix.$$Note that the Hessian is a symmetric matrix, so once you calculate the top right entry, you can copy it into the bottom left entry.
            $endgroup$
            – Minus One-Twelfth
            2 days ago











          • $begingroup$
            @jdoe pls see the edited answer
            $endgroup$
            – V. Vancak
            yesterday
















          • $begingroup$
            Can you say a bit more about that? What would be the entries in the Hessian?
            $endgroup$
            – j doe
            2 days ago










          • $begingroup$
            If you let $l$ be the log-likelihood function and write $vequiv sigma^2$ for simplicity, the Hessian of the log-likelihood function will be equal to $$colorbluebeginbmatrixfracpartial^2 lpartial mu^2 & fracpartial^2 lpartial mu partial v \ fracpartial^2 lpartial mu partial v & fracpartial^2 lpartial v^2endbmatrix.$$Note that the Hessian is a symmetric matrix, so once you calculate the top right entry, you can copy it into the bottom left entry.
            $endgroup$
            – Minus One-Twelfth
            2 days ago











          • $begingroup$
            @jdoe pls see the edited answer
            $endgroup$
            – V. Vancak
            yesterday















          $begingroup$
          Can you say a bit more about that? What would be the entries in the Hessian?
          $endgroup$
          – j doe
          2 days ago




          $begingroup$
          Can you say a bit more about that? What would be the entries in the Hessian?
          $endgroup$
          – j doe
          2 days ago












          $begingroup$
          If you let $l$ be the log-likelihood function and write $vequiv sigma^2$ for simplicity, the Hessian of the log-likelihood function will be equal to $$colorbluebeginbmatrixfracpartial^2 lpartial mu^2 & fracpartial^2 lpartial mu partial v \ fracpartial^2 lpartial mu partial v & fracpartial^2 lpartial v^2endbmatrix.$$Note that the Hessian is a symmetric matrix, so once you calculate the top right entry, you can copy it into the bottom left entry.
          $endgroup$
          – Minus One-Twelfth
          2 days ago





          $begingroup$
          If you let $l$ be the log-likelihood function and write $vequiv sigma^2$ for simplicity, the Hessian of the log-likelihood function will be equal to $$colorbluebeginbmatrixfracpartial^2 lpartial mu^2 & fracpartial^2 lpartial mu partial v \ fracpartial^2 lpartial mu partial v & fracpartial^2 lpartial v^2endbmatrix.$$Note that the Hessian is a symmetric matrix, so once you calculate the top right entry, you can copy it into the bottom left entry.
          $endgroup$
          – Minus One-Twelfth
          2 days ago













          $begingroup$
          @jdoe pls see the edited answer
          $endgroup$
          – V. Vancak
          yesterday




          $begingroup$
          @jdoe pls see the edited answer
          $endgroup$
          – V. Vancak
          yesterday

















          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%2f3141691%2ffisher-information-of-normal-distribution-with-unknown-mean-and-variance%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