Why does finding the partial derivative solve this payoff matrix?
$begingroup$
So I'm taking this math course and I decided to do all the homework the first day of class, and as I was pulling an all-nighter doing it, I got to the topic of game theory and payoff matrices. I never took a formal course in multi-variable calculus, but I learned on my own about partial derivatives and I get the gist of it. I got to this question on the homework:
Question
Well in the textbook, it calls for setting up the rows choices as [x, 1-x]
and having the column's choices being [0,1]
and then repeating the process with [1,0]
to find the optimum row strategy, and then doing the inverse with columns. When I saw how tedious this would be, I noticed that there're only two unknowns, so I could just have an x and y and use some multi-variable calculus.
I simply did this:
matmul
and did dp/dx
and dp/dy
and set each equal to 0 and solved for x and y. I plugged these into the problem and it was the right answer.
Now looking back on this, I can't seem to figure out why this actually solves the problem. I think I don't have a very good understanding of partial derivatives, but from standard Calc 1, I know you would set the derivative to 0 and that would give you the min/max of the function. But translating this to 2 variables is confusing to me, and consequently I've spent the past hour trying to understand why this solves the problem in the first place. Could somebody explain to me very simply how this is actually working and why this finds the optimum strategies?
Thanks!!
matrices multivariable-calculus optimization partial-derivative game-theory
$endgroup$
add a comment |
$begingroup$
So I'm taking this math course and I decided to do all the homework the first day of class, and as I was pulling an all-nighter doing it, I got to the topic of game theory and payoff matrices. I never took a formal course in multi-variable calculus, but I learned on my own about partial derivatives and I get the gist of it. I got to this question on the homework:
Question
Well in the textbook, it calls for setting up the rows choices as [x, 1-x]
and having the column's choices being [0,1]
and then repeating the process with [1,0]
to find the optimum row strategy, and then doing the inverse with columns. When I saw how tedious this would be, I noticed that there're only two unknowns, so I could just have an x and y and use some multi-variable calculus.
I simply did this:
matmul
and did dp/dx
and dp/dy
and set each equal to 0 and solved for x and y. I plugged these into the problem and it was the right answer.
Now looking back on this, I can't seem to figure out why this actually solves the problem. I think I don't have a very good understanding of partial derivatives, but from standard Calc 1, I know you would set the derivative to 0 and that would give you the min/max of the function. But translating this to 2 variables is confusing to me, and consequently I've spent the past hour trying to understand why this solves the problem in the first place. Could somebody explain to me very simply how this is actually working and why this finds the optimum strategies?
Thanks!!
matrices multivariable-calculus optimization partial-derivative game-theory
$endgroup$
add a comment |
$begingroup$
So I'm taking this math course and I decided to do all the homework the first day of class, and as I was pulling an all-nighter doing it, I got to the topic of game theory and payoff matrices. I never took a formal course in multi-variable calculus, but I learned on my own about partial derivatives and I get the gist of it. I got to this question on the homework:
Question
Well in the textbook, it calls for setting up the rows choices as [x, 1-x]
and having the column's choices being [0,1]
and then repeating the process with [1,0]
to find the optimum row strategy, and then doing the inverse with columns. When I saw how tedious this would be, I noticed that there're only two unknowns, so I could just have an x and y and use some multi-variable calculus.
I simply did this:
matmul
and did dp/dx
and dp/dy
and set each equal to 0 and solved for x and y. I plugged these into the problem and it was the right answer.
Now looking back on this, I can't seem to figure out why this actually solves the problem. I think I don't have a very good understanding of partial derivatives, but from standard Calc 1, I know you would set the derivative to 0 and that would give you the min/max of the function. But translating this to 2 variables is confusing to me, and consequently I've spent the past hour trying to understand why this solves the problem in the first place. Could somebody explain to me very simply how this is actually working and why this finds the optimum strategies?
Thanks!!
matrices multivariable-calculus optimization partial-derivative game-theory
$endgroup$
So I'm taking this math course and I decided to do all the homework the first day of class, and as I was pulling an all-nighter doing it, I got to the topic of game theory and payoff matrices. I never took a formal course in multi-variable calculus, but I learned on my own about partial derivatives and I get the gist of it. I got to this question on the homework:
Question
Well in the textbook, it calls for setting up the rows choices as [x, 1-x]
and having the column's choices being [0,1]
and then repeating the process with [1,0]
to find the optimum row strategy, and then doing the inverse with columns. When I saw how tedious this would be, I noticed that there're only two unknowns, so I could just have an x and y and use some multi-variable calculus.
I simply did this:
matmul
and did dp/dx
and dp/dy
and set each equal to 0 and solved for x and y. I plugged these into the problem and it was the right answer.
Now looking back on this, I can't seem to figure out why this actually solves the problem. I think I don't have a very good understanding of partial derivatives, but from standard Calc 1, I know you would set the derivative to 0 and that would give you the min/max of the function. But translating this to 2 variables is confusing to me, and consequently I've spent the past hour trying to understand why this solves the problem in the first place. Could somebody explain to me very simply how this is actually working and why this finds the optimum strategies?
Thanks!!
matrices multivariable-calculus optimization partial-derivative game-theory
matrices multivariable-calculus optimization partial-derivative game-theory
asked Jan 17 at 5:05
Carson PCarson P
11
11
add a comment |
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%2f3076612%2fwhy-does-finding-the-partial-derivative-solve-this-payoff-matrix%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%2f3076612%2fwhy-does-finding-the-partial-derivative-solve-this-payoff-matrix%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