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**George,Y****Member**- Registered: 2006-03-12
- Posts: 1,306

*Last edited by George,Y (2012-04-30 19:36:56)*

**X'(y-Xβ)=0**

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**bobbym****Administrator**- From: Bumpkinland
- Registered: 2009-04-12
- Posts: 92,953

Hi;

I do not think there are closed forms for either of those. But if you could put some bounds on some of the constants an asymptotic form might be possible.

**In mathematics, you don't understand things. You just get used to them.**

**I agree with you regarding the satisfaction and importance of actually computing some numbers. I can't tell you how often I see time and money wasted because someone didn't bother to run the numbers.**

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**George,Y****Member**- Registered: 2006-03-12
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There actually is closed form, but through a different integration.

**X'(y-Xβ)=0**

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**bobbym****Administrator**- From: Bumpkinland
- Registered: 2009-04-12
- Posts: 92,953

A different integration?

**In mathematics, you don't understand things. You just get used to them.**

**I agree with you regarding the satisfaction and importance of actually computing some numbers. I can't tell you how often I see time and money wasted because someone didn't bother to run the numbers.**

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**George,Y****Member**- Registered: 2006-03-12
- Posts: 1,306

bobbym wrote:

A different integration?

I have found a way to integrate this directly, but it is very tricky.

**X'(y-Xβ)=0**

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**anonimnystefy****Real Member**- From: The Foundation
- Registered: 2011-05-23
- Posts: 15,891

I doubt that.

Taking a new step, uttering a new word, is what people fear most. ― Fyodor Dostoyevsky, Crime and Punishment

The knowledge of some things as a function of age is a delta function.

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**bobbym****Administrator**- From: Bumpkinland
- Registered: 2009-04-12
- Posts: 92,953

I would say it is unlikely to but the whole question could be answered by posting the solution. Then it can be checked.

**In mathematics, you don't understand things. You just get used to them.**

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**anonimnystefy****Real Member**- From: The Foundation
- Registered: 2011-05-23
- Posts: 15,891

http://m.wolframalpha.com/input/?i=inte … E2&x=0&y=0

*Last edited by anonimnystefy (2013-12-17 01:29:39)*

Taking a new step, uttering a new word, is what people fear most. ― Fyodor Dostoyevsky, Crime and Punishment

The knowledge of some things as a function of age is a delta function.

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**bobbym****Administrator**- From: Bumpkinland
- Registered: 2009-04-12
- Posts: 92,953

Hi;

That is not his integral.

But even if it were, that is not in closed form.

**In mathematics, you don't understand things. You just get used to them.**

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**anonimnystefy****Real Member**- From: The Foundation
- Registered: 2011-05-23
- Posts: 15,891

It is not his integral, but his can be manipulated into that one with substitutions and manipulations. The point is that Alpha says there's no closed form...

Taking a new step, uttering a new word, is what people fear most. ― Fyodor Dostoyevsky, Crime and Punishment

The knowledge of some things as a function of age is a delta function.

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**bobbym****Administrator**- From: Bumpkinland
- Registered: 2009-04-12
- Posts: 92,953

Hi;

Have you looked at the integral you sent to Alpha in post #8?

**In mathematics, you don't understand things. You just get used to them.**

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**anonimnystefy****Real Member**- From: The Foundation
- Registered: 2011-05-23
- Posts: 15,891

Yes, I have.

Taking a new step, uttering a new word, is what people fear most. ― Fyodor Dostoyevsky, Crime and Punishment

The knowledge of some things as a function of age is a delta function.

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**bobbym****Administrator**- From: Bumpkinland
- Registered: 2009-04-12
- Posts: 92,953

Then you know it is not and can never be his integral.

**In mathematics, you don't understand things. You just get used to them.**

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**anonimnystefy****Real Member**- From: The Foundation
- Registered: 2011-05-23
- Posts: 15,891

Fixed.

Taking a new step, uttering a new word, is what people fear most. ― Fyodor Dostoyevsky, Crime and Punishment

The knowledge of some things as a function of age is a delta function.

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**bobbym****Administrator**- From: Bumpkinland
- Registered: 2009-04-12
- Posts: 92,953

Brings us back to post #7. The fact that both M's can not do the integral does mean there is a high probability that it is intractable. But they are not infallible, so I think if George would post his answer the whole thing can resolved quickly.

**In mathematics, you don't understand things. You just get used to them.**

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**anonimnystefy****Real Member**- From: The Foundation
- Registered: 2011-05-23
- Posts: 15,891

Do you think some progress can be made using DUIT?

Taking a new step, uttering a new word, is what people fear most. ― Fyodor Dostoyevsky, Crime and Punishment

The knowledge of some things as a function of age is a delta function.

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**bobbym****Administrator**- From: Bumpkinland
- Registered: 2009-04-12
- Posts: 92,953

I have not tried but it sure does respond well to numerical integration for any T.

**In mathematics, you don't understand things. You just get used to them.**

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**George,Y****Member**- Registered: 2006-03-12
- Posts: 1,306

Sorry guys, I made a mistake, the question should be:

*Last edited by George,Y (2013-12-29 01:12:55)*

**X'(y-Xβ)=0**

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**anonimnystefy****Real Member**- From: The Foundation
- Registered: 2011-05-23
- Posts: 15,891

That does not change much.

Taking a new step, uttering a new word, is what people fear most. ― Fyodor Dostoyevsky, Crime and Punishment

The knowledge of some things as a function of age is a delta function.

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**bobbym****Administrator**- From: Bumpkinland
- Registered: 2009-04-12
- Posts: 92,953

Hi George,Y;

That does not change much.

Yes, I think it is time to show your solution. I am willing to bet 21% of my bankroll, a whopping $1.16 that the solution is wrong.

**In mathematics, you don't understand things. You just get used to them.**

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**George,Y****Member**- Registered: 2006-03-12
- Posts: 1,306

*Last edited by George,Y (2013-12-30 22:11:21)*

**X'(y-Xβ)=0**

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**bobbym****Administrator**- From: Bumpkinland
- Registered: 2009-04-12
- Posts: 92,953

Hi;

What is d?

**In mathematics, you don't understand things. You just get used to them.**

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**George,Y****Member**- Registered: 2006-03-12
- Posts: 1,306

After this change of variable, I think now the question is easier.

**X'(y-Xβ)=0**

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**George,Y****Member**- Registered: 2006-03-12
- Posts: 1,306

bobbym wrote:

Hi;

What is d?

d is the differential operator

**X'(y-Xβ)=0**

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**bobbym****Administrator**- From: Bumpkinland
- Registered: 2009-04-12
- Posts: 92,953

What is the new integral?

**In mathematics, you don't understand things. You just get used to them.**

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