Is taking $3sigma$ limits for bivariate correlated random variables as the confidence limits an under estimation?

The name of the pictureThe name of the pictureThe name of the pictureClash Royale CLAN TAG#URR8PPP











up vote
1
down vote

favorite
1












If the two random variables are uncorrelated, $3sigma$ limit would mean that the random variables lie inside a hyperrectangle with center coordinates being means of random variables. But if two random variables are correlated, is taking a hyperrectangle instead of corresponding hyperellipsoid an under-approximation or altogether not theoretically correct?







share|cite|improve this question



















  • Suppose you are talking about constructing a confidence region for Bivariate normal, then you may refer to, e.g. stats.stackexchange.com/questions/29860/… for using Hotelling's T to construct the region. Note that the region formed by the Cartaesian product of the marginal CI have a lower coverage probability, and it is not optimal in the sense that the volume of the region is larger.
    – BGM
    Jul 25 at 16:45














up vote
1
down vote

favorite
1












If the two random variables are uncorrelated, $3sigma$ limit would mean that the random variables lie inside a hyperrectangle with center coordinates being means of random variables. But if two random variables are correlated, is taking a hyperrectangle instead of corresponding hyperellipsoid an under-approximation or altogether not theoretically correct?







share|cite|improve this question



















  • Suppose you are talking about constructing a confidence region for Bivariate normal, then you may refer to, e.g. stats.stackexchange.com/questions/29860/… for using Hotelling's T to construct the region. Note that the region formed by the Cartaesian product of the marginal CI have a lower coverage probability, and it is not optimal in the sense that the volume of the region is larger.
    – BGM
    Jul 25 at 16:45












up vote
1
down vote

favorite
1









up vote
1
down vote

favorite
1






1





If the two random variables are uncorrelated, $3sigma$ limit would mean that the random variables lie inside a hyperrectangle with center coordinates being means of random variables. But if two random variables are correlated, is taking a hyperrectangle instead of corresponding hyperellipsoid an under-approximation or altogether not theoretically correct?







share|cite|improve this question











If the two random variables are uncorrelated, $3sigma$ limit would mean that the random variables lie inside a hyperrectangle with center coordinates being means of random variables. But if two random variables are correlated, is taking a hyperrectangle instead of corresponding hyperellipsoid an under-approximation or altogether not theoretically correct?









share|cite|improve this question










share|cite|improve this question




share|cite|improve this question









asked Jul 25 at 14:30









NavE3n Naveen

61




61











  • Suppose you are talking about constructing a confidence region for Bivariate normal, then you may refer to, e.g. stats.stackexchange.com/questions/29860/… for using Hotelling's T to construct the region. Note that the region formed by the Cartaesian product of the marginal CI have a lower coverage probability, and it is not optimal in the sense that the volume of the region is larger.
    – BGM
    Jul 25 at 16:45
















  • Suppose you are talking about constructing a confidence region for Bivariate normal, then you may refer to, e.g. stats.stackexchange.com/questions/29860/… for using Hotelling's T to construct the region. Note that the region formed by the Cartaesian product of the marginal CI have a lower coverage probability, and it is not optimal in the sense that the volume of the region is larger.
    – BGM
    Jul 25 at 16:45















Suppose you are talking about constructing a confidence region for Bivariate normal, then you may refer to, e.g. stats.stackexchange.com/questions/29860/… for using Hotelling's T to construct the region. Note that the region formed by the Cartaesian product of the marginal CI have a lower coverage probability, and it is not optimal in the sense that the volume of the region is larger.
– BGM
Jul 25 at 16:45




Suppose you are talking about constructing a confidence region for Bivariate normal, then you may refer to, e.g. stats.stackexchange.com/questions/29860/… for using Hotelling's T to construct the region. Note that the region formed by the Cartaesian product of the marginal CI have a lower coverage probability, and it is not optimal in the sense that the volume of the region is larger.
– BGM
Jul 25 at 16:45















active

oldest

votes











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',
convertImagesToLinks: true,
noModals: false,
showLowRepImageUploadWarning: true,
reputationToPostImages: 10,
bindNavPrevention: true,
postfix: "",
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%2f2862474%2fis-taking-3-sigma-limits-for-bivariate-correlated-random-variables-as-the-conf%23new-answer', 'question_page');

);

Post as a guest



































active

oldest

votes













active

oldest

votes









active

oldest

votes






active

oldest

votes










 

draft saved


draft discarded


























 


draft saved


draft discarded














StackExchange.ready(
function ()
StackExchange.openid.initPostLogin('.new-post-login', 'https%3a%2f%2fmath.stackexchange.com%2fquestions%2f2862474%2fis-taking-3-sigma-limits-for-bivariate-correlated-random-variables-as-the-conf%23new-answer', 'question_page');

);

Post as a guest













































































Comments

Popular posts from this blog

Color the edges and diagonals of a regular polygon

Relationship between determinant of matrix and determinant of adjoint?

What is the equation of a 3D cone with generalised tilt?