Probability density function (PDF) of a scaled non-central chi squared distribution
$begingroup$
I know that:
If $X$ is exponentially distributed with a rate parameter $lambda$, then $cX$ is exponentially distributed with a rate parameter $frac{lambda}{c}$.
If $X$ is central chi-squared distributed with $nu$ degree of freedom, then $cX$ is gamma distributed with shape $frac{nu}{2}$ and scale parameter $2c$.
where $c$ is a positive constant.
My question is:
If $X$ is non-central chi-squared distributed with $nu$ degree of freedom, then how is $cX$ distributed? What is the pdf of $cX$ ?
statistics probability-distributions
$endgroup$
add a comment |
$begingroup$
I know that:
If $X$ is exponentially distributed with a rate parameter $lambda$, then $cX$ is exponentially distributed with a rate parameter $frac{lambda}{c}$.
If $X$ is central chi-squared distributed with $nu$ degree of freedom, then $cX$ is gamma distributed with shape $frac{nu}{2}$ and scale parameter $2c$.
where $c$ is a positive constant.
My question is:
If $X$ is non-central chi-squared distributed with $nu$ degree of freedom, then how is $cX$ distributed? What is the pdf of $cX$ ?
statistics probability-distributions
$endgroup$
$begingroup$
In general, the PDF of $cX$ is $frac{1}{c} f_X(t/c)$ where $f_X$ is the PDF of $X$. I don't know of a nice name for the distribution of your particular $cX$ though.
$endgroup$
– angryavian
Jan 1 at 5:48
$begingroup$
Thank you @angryavian. The information you gave is very helpful. By the way, is there a reference where the PDF of $cX$ is $frac{1}{c}f_X(frac{t}{c}) $?
$endgroup$
– M.A.N
Jan 1 at 7:07
$begingroup$
This is a special case of change of variables.
$endgroup$
– angryavian
Jan 1 at 17:22
add a comment |
$begingroup$
I know that:
If $X$ is exponentially distributed with a rate parameter $lambda$, then $cX$ is exponentially distributed with a rate parameter $frac{lambda}{c}$.
If $X$ is central chi-squared distributed with $nu$ degree of freedom, then $cX$ is gamma distributed with shape $frac{nu}{2}$ and scale parameter $2c$.
where $c$ is a positive constant.
My question is:
If $X$ is non-central chi-squared distributed with $nu$ degree of freedom, then how is $cX$ distributed? What is the pdf of $cX$ ?
statistics probability-distributions
$endgroup$
I know that:
If $X$ is exponentially distributed with a rate parameter $lambda$, then $cX$ is exponentially distributed with a rate parameter $frac{lambda}{c}$.
If $X$ is central chi-squared distributed with $nu$ degree of freedom, then $cX$ is gamma distributed with shape $frac{nu}{2}$ and scale parameter $2c$.
where $c$ is a positive constant.
My question is:
If $X$ is non-central chi-squared distributed with $nu$ degree of freedom, then how is $cX$ distributed? What is the pdf of $cX$ ?
statistics probability-distributions
statistics probability-distributions
asked Jan 1 at 4:18
M.A.NM.A.N
1078
1078
$begingroup$
In general, the PDF of $cX$ is $frac{1}{c} f_X(t/c)$ where $f_X$ is the PDF of $X$. I don't know of a nice name for the distribution of your particular $cX$ though.
$endgroup$
– angryavian
Jan 1 at 5:48
$begingroup$
Thank you @angryavian. The information you gave is very helpful. By the way, is there a reference where the PDF of $cX$ is $frac{1}{c}f_X(frac{t}{c}) $?
$endgroup$
– M.A.N
Jan 1 at 7:07
$begingroup$
This is a special case of change of variables.
$endgroup$
– angryavian
Jan 1 at 17:22
add a comment |
$begingroup$
In general, the PDF of $cX$ is $frac{1}{c} f_X(t/c)$ where $f_X$ is the PDF of $X$. I don't know of a nice name for the distribution of your particular $cX$ though.
$endgroup$
– angryavian
Jan 1 at 5:48
$begingroup$
Thank you @angryavian. The information you gave is very helpful. By the way, is there a reference where the PDF of $cX$ is $frac{1}{c}f_X(frac{t}{c}) $?
$endgroup$
– M.A.N
Jan 1 at 7:07
$begingroup$
This is a special case of change of variables.
$endgroup$
– angryavian
Jan 1 at 17:22
$begingroup$
In general, the PDF of $cX$ is $frac{1}{c} f_X(t/c)$ where $f_X$ is the PDF of $X$. I don't know of a nice name for the distribution of your particular $cX$ though.
$endgroup$
– angryavian
Jan 1 at 5:48
$begingroup$
In general, the PDF of $cX$ is $frac{1}{c} f_X(t/c)$ where $f_X$ is the PDF of $X$. I don't know of a nice name for the distribution of your particular $cX$ though.
$endgroup$
– angryavian
Jan 1 at 5:48
$begingroup$
Thank you @angryavian. The information you gave is very helpful. By the way, is there a reference where the PDF of $cX$ is $frac{1}{c}f_X(frac{t}{c}) $?
$endgroup$
– M.A.N
Jan 1 at 7:07
$begingroup$
Thank you @angryavian. The information you gave is very helpful. By the way, is there a reference where the PDF of $cX$ is $frac{1}{c}f_X(frac{t}{c}) $?
$endgroup$
– M.A.N
Jan 1 at 7:07
$begingroup$
This is a special case of change of variables.
$endgroup$
– angryavian
Jan 1 at 17:22
$begingroup$
This is a special case of change of variables.
$endgroup$
– angryavian
Jan 1 at 17:22
add a comment |
0
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',
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
});
}
});
Sign up or log in
StackExchange.ready(function () {
StackExchange.helpers.onClickDraftSave('#login-link');
});
Sign up using Google
Sign up using Facebook
Sign up using Email and Password
Post as a guest
Required, but never shown
StackExchange.ready(
function () {
StackExchange.openid.initPostLogin('.new-post-login', 'https%3a%2f%2fmath.stackexchange.com%2fquestions%2f3058215%2fprobability-density-function-pdf-of-a-scaled-non-central-chi-squared-distribut%23new-answer', 'question_page');
}
);
Post as a guest
Required, but never shown
0
active
oldest
votes
0
active
oldest
votes
active
oldest
votes
active
oldest
votes
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.
Sign up or log in
StackExchange.ready(function () {
StackExchange.helpers.onClickDraftSave('#login-link');
});
Sign up using Google
Sign up using Facebook
Sign up using Email and Password
Post as a guest
Required, but never shown
StackExchange.ready(
function () {
StackExchange.openid.initPostLogin('.new-post-login', 'https%3a%2f%2fmath.stackexchange.com%2fquestions%2f3058215%2fprobability-density-function-pdf-of-a-scaled-non-central-chi-squared-distribut%23new-answer', 'question_page');
}
);
Post as a guest
Required, but never shown
Sign up or log in
StackExchange.ready(function () {
StackExchange.helpers.onClickDraftSave('#login-link');
});
Sign up using Google
Sign up using Facebook
Sign up using Email and Password
Post as a guest
Required, but never shown
Sign up or log in
StackExchange.ready(function () {
StackExchange.helpers.onClickDraftSave('#login-link');
});
Sign up using Google
Sign up using Facebook
Sign up using Email and Password
Post as a guest
Required, but never shown
Sign up or log in
StackExchange.ready(function () {
StackExchange.helpers.onClickDraftSave('#login-link');
});
Sign up using Google
Sign up using Facebook
Sign up using Email and Password
Sign up using Google
Sign up using Facebook
Sign up using Email and Password
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
$begingroup$
In general, the PDF of $cX$ is $frac{1}{c} f_X(t/c)$ where $f_X$ is the PDF of $X$. I don't know of a nice name for the distribution of your particular $cX$ though.
$endgroup$
– angryavian
Jan 1 at 5:48
$begingroup$
Thank you @angryavian. The information you gave is very helpful. By the way, is there a reference where the PDF of $cX$ is $frac{1}{c}f_X(frac{t}{c}) $?
$endgroup$
– M.A.N
Jan 1 at 7:07
$begingroup$
This is a special case of change of variables.
$endgroup$
– angryavian
Jan 1 at 17:22