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**George,Y****Member**- Registered: 2006-03-12
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*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
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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.

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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
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A different integration?

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**George,Y****Member**- Registered: 2006-03-12
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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: Harlan's World
- Registered: 2011-05-23
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I doubt that.

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**bobbym****Administrator**- From: Bumpkinland
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I would say it is unlikely to but the whole question could be answered by posting the solution. Then it can be checked.

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**anonimnystefy****Real Member**- From: Harlan's World
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http://m.wolframalpha.com/input/?i=inte … E2&x=0&y=0

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

Here lies the reader who will never open this book. He is forever dead.

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: 98,092

Hi;

That is not his integral.

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

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**If it ain't broke, fix it until it is.**

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**anonimnystefy****Real Member**- From: Harlan's World
- Registered: 2011-05-23
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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...

Here lies the reader who will never open this book. He is forever dead.

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: 98,092

Hi;

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

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**If it ain't broke, fix it until it is.**

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**anonimnystefy****Real Member**- From: Harlan's World
- Registered: 2011-05-23
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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: 98,092

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

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**If it ain't broke, fix it until it is.**

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**anonimnystefy****Real Member**- From: Harlan's World
- Registered: 2011-05-23
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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: 98,092

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.

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**If it ain't broke, fix it until it is.**

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**anonimnystefy****Real Member**- From: Harlan's World
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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
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I have not tried but it sure does respond well to numerical integration for any T.

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**If it ain't broke, fix it until it is.**

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**George,Y****Member**- Registered: 2006-03-12
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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: Harlan's World
- Registered: 2011-05-23
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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: 98,092

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.

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**George,Y****Member**- Registered: 2006-03-12
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*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: 98,092

Hi;

What is d?

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**George,Y****Member**- Registered: 2006-03-12
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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
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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: 98,092

What is the new integral?

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