The name of a mathematical property












0












$begingroup$


When two Gaussian equations are multipled together, the outcome is another Gaussian distribution. Roger R. Labbe Jr., author of "Kalman and Bayesian Filters in Python" calls this property "rare" and points out that $sin(x) sin(y)$, for example, does not yield a $sin()$.



My question is simply, does that property have a name?










share|cite|improve this question











$endgroup$












  • $begingroup$
    What do you mean "two Gaussian distributions are multiplied together"? Two Gaussian random variables or two Gaussian densities?
    $endgroup$
    – Henry
    Dec 18 '18 at 22:08










  • $begingroup$
    The exact quote is "The mathematics of the Kalman Flter is beautiful in part due to the Gaussian equation being so special. It is nonlinear, but when we add and multipy it using linear algebra we get another Gaussian equation as a result"
    $endgroup$
    – user120911
    Dec 18 '18 at 22:15






  • 1




    $begingroup$
    What do you call "Gaussian equation" ?
    $endgroup$
    – Damien
    Dec 18 '18 at 22:34










  • $begingroup$
    The author shouldn’t have used the word “equation” — this is a terrible red flag. All the author is saying is that the product of two exponentials (and in particular Gaussians) is again an exponential. In other words, the class of exponential functions (those of the form $e^{f(t)}$) is closed under multiplication.
    $endgroup$
    – symplectomorphic
    Dec 18 '18 at 23:56
















0












$begingroup$


When two Gaussian equations are multipled together, the outcome is another Gaussian distribution. Roger R. Labbe Jr., author of "Kalman and Bayesian Filters in Python" calls this property "rare" and points out that $sin(x) sin(y)$, for example, does not yield a $sin()$.



My question is simply, does that property have a name?










share|cite|improve this question











$endgroup$












  • $begingroup$
    What do you mean "two Gaussian distributions are multiplied together"? Two Gaussian random variables or two Gaussian densities?
    $endgroup$
    – Henry
    Dec 18 '18 at 22:08










  • $begingroup$
    The exact quote is "The mathematics of the Kalman Flter is beautiful in part due to the Gaussian equation being so special. It is nonlinear, but when we add and multipy it using linear algebra we get another Gaussian equation as a result"
    $endgroup$
    – user120911
    Dec 18 '18 at 22:15






  • 1




    $begingroup$
    What do you call "Gaussian equation" ?
    $endgroup$
    – Damien
    Dec 18 '18 at 22:34










  • $begingroup$
    The author shouldn’t have used the word “equation” — this is a terrible red flag. All the author is saying is that the product of two exponentials (and in particular Gaussians) is again an exponential. In other words, the class of exponential functions (those of the form $e^{f(t)}$) is closed under multiplication.
    $endgroup$
    – symplectomorphic
    Dec 18 '18 at 23:56














0












0








0





$begingroup$


When two Gaussian equations are multipled together, the outcome is another Gaussian distribution. Roger R. Labbe Jr., author of "Kalman and Bayesian Filters in Python" calls this property "rare" and points out that $sin(x) sin(y)$, for example, does not yield a $sin()$.



My question is simply, does that property have a name?










share|cite|improve this question











$endgroup$




When two Gaussian equations are multipled together, the outcome is another Gaussian distribution. Roger R. Labbe Jr., author of "Kalman and Bayesian Filters in Python" calls this property "rare" and points out that $sin(x) sin(y)$, for example, does not yield a $sin()$.



My question is simply, does that property have a name?







definition normal-distribution kalman-filter






share|cite|improve this question















share|cite|improve this question













share|cite|improve this question




share|cite|improve this question








edited Dec 18 '18 at 22:43









Will Fisher

4,05311132




4,05311132










asked Dec 18 '18 at 21:49









user120911user120911

231110




231110












  • $begingroup$
    What do you mean "two Gaussian distributions are multiplied together"? Two Gaussian random variables or two Gaussian densities?
    $endgroup$
    – Henry
    Dec 18 '18 at 22:08










  • $begingroup$
    The exact quote is "The mathematics of the Kalman Flter is beautiful in part due to the Gaussian equation being so special. It is nonlinear, but when we add and multipy it using linear algebra we get another Gaussian equation as a result"
    $endgroup$
    – user120911
    Dec 18 '18 at 22:15






  • 1




    $begingroup$
    What do you call "Gaussian equation" ?
    $endgroup$
    – Damien
    Dec 18 '18 at 22:34










  • $begingroup$
    The author shouldn’t have used the word “equation” — this is a terrible red flag. All the author is saying is that the product of two exponentials (and in particular Gaussians) is again an exponential. In other words, the class of exponential functions (those of the form $e^{f(t)}$) is closed under multiplication.
    $endgroup$
    – symplectomorphic
    Dec 18 '18 at 23:56


















  • $begingroup$
    What do you mean "two Gaussian distributions are multiplied together"? Two Gaussian random variables or two Gaussian densities?
    $endgroup$
    – Henry
    Dec 18 '18 at 22:08










  • $begingroup$
    The exact quote is "The mathematics of the Kalman Flter is beautiful in part due to the Gaussian equation being so special. It is nonlinear, but when we add and multipy it using linear algebra we get another Gaussian equation as a result"
    $endgroup$
    – user120911
    Dec 18 '18 at 22:15






  • 1




    $begingroup$
    What do you call "Gaussian equation" ?
    $endgroup$
    – Damien
    Dec 18 '18 at 22:34










  • $begingroup$
    The author shouldn’t have used the word “equation” — this is a terrible red flag. All the author is saying is that the product of two exponentials (and in particular Gaussians) is again an exponential. In other words, the class of exponential functions (those of the form $e^{f(t)}$) is closed under multiplication.
    $endgroup$
    – symplectomorphic
    Dec 18 '18 at 23:56
















$begingroup$
What do you mean "two Gaussian distributions are multiplied together"? Two Gaussian random variables or two Gaussian densities?
$endgroup$
– Henry
Dec 18 '18 at 22:08




$begingroup$
What do you mean "two Gaussian distributions are multiplied together"? Two Gaussian random variables or two Gaussian densities?
$endgroup$
– Henry
Dec 18 '18 at 22:08












$begingroup$
The exact quote is "The mathematics of the Kalman Flter is beautiful in part due to the Gaussian equation being so special. It is nonlinear, but when we add and multipy it using linear algebra we get another Gaussian equation as a result"
$endgroup$
– user120911
Dec 18 '18 at 22:15




$begingroup$
The exact quote is "The mathematics of the Kalman Flter is beautiful in part due to the Gaussian equation being so special. It is nonlinear, but when we add and multipy it using linear algebra we get another Gaussian equation as a result"
$endgroup$
– user120911
Dec 18 '18 at 22:15




1




1




$begingroup$
What do you call "Gaussian equation" ?
$endgroup$
– Damien
Dec 18 '18 at 22:34




$begingroup$
What do you call "Gaussian equation" ?
$endgroup$
– Damien
Dec 18 '18 at 22:34












$begingroup$
The author shouldn’t have used the word “equation” — this is a terrible red flag. All the author is saying is that the product of two exponentials (and in particular Gaussians) is again an exponential. In other words, the class of exponential functions (those of the form $e^{f(t)}$) is closed under multiplication.
$endgroup$
– symplectomorphic
Dec 18 '18 at 23:56




$begingroup$
The author shouldn’t have used the word “equation” — this is a terrible red flag. All the author is saying is that the product of two exponentials (and in particular Gaussians) is again an exponential. In other words, the class of exponential functions (those of the form $e^{f(t)}$) is closed under multiplication.
$endgroup$
– symplectomorphic
Dec 18 '18 at 23:56










1 Answer
1






active

oldest

votes


















3












$begingroup$

I would call it "closure under multiplication".






share|cite|improve this answer









$endgroup$









  • 1




    $begingroup$
    This is a comment, IMO.
    $endgroup$
    – coffeemath
    Dec 18 '18 at 22:17










  • $begingroup$
    @coffeemath while the answer is short, it is an answer. It is incomplete, though. Give evidence that this is standard nomenclature. For instance: "groups are closed under multiplication as a definition" cite that sort of language in literature.
    $endgroup$
    – Larry B.
    Dec 18 '18 at 23:21










  • $begingroup$
    user247327-- Re-reading OP's post I agree it asked only for a name of the property. I can delete comment if you want.
    $endgroup$
    – coffeemath
    Dec 19 '18 at 5:36












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%2f3045753%2fthe-name-of-a-mathematical-property%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









3












$begingroup$

I would call it "closure under multiplication".






share|cite|improve this answer









$endgroup$









  • 1




    $begingroup$
    This is a comment, IMO.
    $endgroup$
    – coffeemath
    Dec 18 '18 at 22:17










  • $begingroup$
    @coffeemath while the answer is short, it is an answer. It is incomplete, though. Give evidence that this is standard nomenclature. For instance: "groups are closed under multiplication as a definition" cite that sort of language in literature.
    $endgroup$
    – Larry B.
    Dec 18 '18 at 23:21










  • $begingroup$
    user247327-- Re-reading OP's post I agree it asked only for a name of the property. I can delete comment if you want.
    $endgroup$
    – coffeemath
    Dec 19 '18 at 5:36
















3












$begingroup$

I would call it "closure under multiplication".






share|cite|improve this answer









$endgroup$









  • 1




    $begingroup$
    This is a comment, IMO.
    $endgroup$
    – coffeemath
    Dec 18 '18 at 22:17










  • $begingroup$
    @coffeemath while the answer is short, it is an answer. It is incomplete, though. Give evidence that this is standard nomenclature. For instance: "groups are closed under multiplication as a definition" cite that sort of language in literature.
    $endgroup$
    – Larry B.
    Dec 18 '18 at 23:21










  • $begingroup$
    user247327-- Re-reading OP's post I agree it asked only for a name of the property. I can delete comment if you want.
    $endgroup$
    – coffeemath
    Dec 19 '18 at 5:36














3












3








3





$begingroup$

I would call it "closure under multiplication".






share|cite|improve this answer









$endgroup$



I would call it "closure under multiplication".







share|cite|improve this answer












share|cite|improve this answer



share|cite|improve this answer










answered Dec 18 '18 at 22:12









user247327user247327

11.6k1516




11.6k1516








  • 1




    $begingroup$
    This is a comment, IMO.
    $endgroup$
    – coffeemath
    Dec 18 '18 at 22:17










  • $begingroup$
    @coffeemath while the answer is short, it is an answer. It is incomplete, though. Give evidence that this is standard nomenclature. For instance: "groups are closed under multiplication as a definition" cite that sort of language in literature.
    $endgroup$
    – Larry B.
    Dec 18 '18 at 23:21










  • $begingroup$
    user247327-- Re-reading OP's post I agree it asked only for a name of the property. I can delete comment if you want.
    $endgroup$
    – coffeemath
    Dec 19 '18 at 5:36














  • 1




    $begingroup$
    This is a comment, IMO.
    $endgroup$
    – coffeemath
    Dec 18 '18 at 22:17










  • $begingroup$
    @coffeemath while the answer is short, it is an answer. It is incomplete, though. Give evidence that this is standard nomenclature. For instance: "groups are closed under multiplication as a definition" cite that sort of language in literature.
    $endgroup$
    – Larry B.
    Dec 18 '18 at 23:21










  • $begingroup$
    user247327-- Re-reading OP's post I agree it asked only for a name of the property. I can delete comment if you want.
    $endgroup$
    – coffeemath
    Dec 19 '18 at 5:36








1




1




$begingroup$
This is a comment, IMO.
$endgroup$
– coffeemath
Dec 18 '18 at 22:17




$begingroup$
This is a comment, IMO.
$endgroup$
– coffeemath
Dec 18 '18 at 22:17












$begingroup$
@coffeemath while the answer is short, it is an answer. It is incomplete, though. Give evidence that this is standard nomenclature. For instance: "groups are closed under multiplication as a definition" cite that sort of language in literature.
$endgroup$
– Larry B.
Dec 18 '18 at 23:21




$begingroup$
@coffeemath while the answer is short, it is an answer. It is incomplete, though. Give evidence that this is standard nomenclature. For instance: "groups are closed under multiplication as a definition" cite that sort of language in literature.
$endgroup$
– Larry B.
Dec 18 '18 at 23:21












$begingroup$
user247327-- Re-reading OP's post I agree it asked only for a name of the property. I can delete comment if you want.
$endgroup$
– coffeemath
Dec 19 '18 at 5:36




$begingroup$
user247327-- Re-reading OP's post I agree it asked only for a name of the property. I can delete comment if you want.
$endgroup$
– coffeemath
Dec 19 '18 at 5:36


















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%2f3045753%2fthe-name-of-a-mathematical-property%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

Plaza Victoria

In PowerPoint, is there a keyboard shortcut for bulleted / numbered list?

How to put 3 figures in Latex with 2 figures side by side and 1 below these side by side images but in...