Upperbounding the expected value of an L2-norm difference
I am trying to find an upperbound for $$E_Ileft[sum_{k=I}^n a_k^2 - sum_{k=I}^n b_k^2right],$$ where the expectation is taken over the random variable $I$. The tuples $a$ and $b$ are real and $I$ may take values on ${1,...,n}$.
I checked Jensen's inequalites but without success. Any help would be appreciated.
probability inequality norm jensen-inequality
add a comment |
I am trying to find an upperbound for $$E_Ileft[sum_{k=I}^n a_k^2 - sum_{k=I}^n b_k^2right],$$ where the expectation is taken over the random variable $I$. The tuples $a$ and $b$ are real and $I$ may take values on ${1,...,n}$.
I checked Jensen's inequalites but without success. Any help would be appreciated.
probability inequality norm jensen-inequality
What is the relation between $a_k, b_k$ and $I$?
– herb steinberg
Nov 26 '18 at 22:50
Assuming you seek a bound on the expectation of a random length sum of fixed real numbers, clearly $||a||_2^2=sum_{k=1}^n a_k^2$ is an upper bound.
– Macavity
Nov 27 '18 at 1:29
add a comment |
I am trying to find an upperbound for $$E_Ileft[sum_{k=I}^n a_k^2 - sum_{k=I}^n b_k^2right],$$ where the expectation is taken over the random variable $I$. The tuples $a$ and $b$ are real and $I$ may take values on ${1,...,n}$.
I checked Jensen's inequalites but without success. Any help would be appreciated.
probability inequality norm jensen-inequality
I am trying to find an upperbound for $$E_Ileft[sum_{k=I}^n a_k^2 - sum_{k=I}^n b_k^2right],$$ where the expectation is taken over the random variable $I$. The tuples $a$ and $b$ are real and $I$ may take values on ${1,...,n}$.
I checked Jensen's inequalites but without success. Any help would be appreciated.
probability inequality norm jensen-inequality
probability inequality norm jensen-inequality
asked Nov 26 '18 at 19:04
Embid
1
1
What is the relation between $a_k, b_k$ and $I$?
– herb steinberg
Nov 26 '18 at 22:50
Assuming you seek a bound on the expectation of a random length sum of fixed real numbers, clearly $||a||_2^2=sum_{k=1}^n a_k^2$ is an upper bound.
– Macavity
Nov 27 '18 at 1:29
add a comment |
What is the relation between $a_k, b_k$ and $I$?
– herb steinberg
Nov 26 '18 at 22:50
Assuming you seek a bound on the expectation of a random length sum of fixed real numbers, clearly $||a||_2^2=sum_{k=1}^n a_k^2$ is an upper bound.
– Macavity
Nov 27 '18 at 1:29
What is the relation between $a_k, b_k$ and $I$?
– herb steinberg
Nov 26 '18 at 22:50
What is the relation between $a_k, b_k$ and $I$?
– herb steinberg
Nov 26 '18 at 22:50
Assuming you seek a bound on the expectation of a random length sum of fixed real numbers, clearly $||a||_2^2=sum_{k=1}^n a_k^2$ is an upper bound.
– Macavity
Nov 27 '18 at 1:29
Assuming you seek a bound on the expectation of a random length sum of fixed real numbers, clearly $||a||_2^2=sum_{k=1}^n a_k^2$ is an upper bound.
– Macavity
Nov 27 '18 at 1:29
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%2f3014764%2fupperbounding-the-expected-value-of-an-l2-norm-difference%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.
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.
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%2f3014764%2fupperbounding-the-expected-value-of-an-l2-norm-difference%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
What is the relation between $a_k, b_k$ and $I$?
– herb steinberg
Nov 26 '18 at 22:50
Assuming you seek a bound on the expectation of a random length sum of fixed real numbers, clearly $||a||_2^2=sum_{k=1}^n a_k^2$ is an upper bound.
– Macavity
Nov 27 '18 at 1:29