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#226 2013-03-20 03:26:45

bobbym
Administrator
From: Bumpkinland
Registered: 2009-04-12
Posts: 88,714

Re: Expectation

For me it always was one of the best.


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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#227 2013-04-01 00:53:13

anonimnystefy
Real Member
From: The Foundation
Registered: 2011-05-23
Posts: 15,603

Re: Expectation

Is there a pattern in these?

Last edited by anonimnystefy (2013-04-01 00:53:28)


“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

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#228 2013-04-01 01:07:12

bobbym
Administrator
From: Bumpkinland
Registered: 2009-04-12
Posts: 88,714

Re: Expectation

Up - down or left - right?


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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#229 2013-04-01 01:08:15

anonimnystefy
Real Member
From: The Foundation
Registered: 2011-05-23
Posts: 15,603

Re: Expectation

Both.


“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

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#230 2013-04-01 01:09:05

bobbym
Administrator
From: Bumpkinland
Registered: 2009-04-12
Posts: 88,714

Re: Expectation

How about the first column, can you supply more?


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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#231 2013-04-01 01:10:21

anonimnystefy
Real Member
From: The Foundation
Registered: 2011-05-23
Posts: 15,603

Re: Expectation

11, 12, 13, 14, 15...


“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

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#232 2013-04-01 01:12:00

bobbym
Administrator
From: Bumpkinland
Registered: 2009-04-12
Posts: 88,714

Re: Expectation

Hi;

Yes, the more the merrier!


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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#233 2013-04-01 01:14:54

anonimnystefy
Real Member
From: The Foundation
Registered: 2011-05-23
Posts: 15,603

Re: Expectation

Well, the first column is obvious. Those are the natural numbers...


“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

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#234 2013-04-01 01:28:13

bobbym
Administrator
From: Bumpkinland
Registered: 2009-04-12
Posts: 88,714

Re: Expectation

Yikes! That is a good one. The second column.


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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#235 2013-04-01 01:30:51

anonimnystefy
Real Member
From: The Foundation
Registered: 2011-05-23
Posts: 15,603

Re: Expectation

You can generate all the numbers you need:

f[bins_, k_] := Sum[i*(i - k)!/(bins^(i - 1))*Binomial[i - 1, k - 1]*Coefficient[(Sum[x^j/j!, {j, 0, k - 1}])^(bins - 1), x, i - k], {i,k, bins*(k - 1) + 1}]
MatrixForm[Table[Table[f[i, j], {i, 1, 10}], {j, 1, 10}]]

“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

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#236 2013-04-01 01:36:25

bobbym
Administrator
From: Bumpkinland
Registered: 2009-04-12
Posts: 88,714

Re: Expectation

Hmmm, that looks like M code to me.


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.

Offline

#237 2013-04-01 01:45:02

anonimnystefy
Real Member
From: The Foundation
Registered: 2011-05-23
Posts: 15,603

Re: Expectation

It is M code.

And the function f is the function which calculates the expected value for k balls to appear in a bin, where the number of bins is represented bt the number "bins".


“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

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#238 2013-04-01 01:51:48

bobbym
Administrator
From: Bumpkinland
Registered: 2009-04-12
Posts: 88,714

Re: Expectation

Are you aware of its awesome firepower?


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.

Offline

#239 2013-04-01 02:03:10

anonimnystefy
Real Member
From: The Foundation
Registered: 2011-05-23
Posts: 15,603

Re: Expectation

Like what?


“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

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#240 2013-04-01 02:04:33

bobbym
Administrator
From: Bumpkinland
Registered: 2009-04-12
Posts: 88,714

Re: Expectation

FindSequenceFunction for one thing...


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.

Offline

#241 2013-04-01 02:08:37

anonimnystefy
Real Member
From: The Foundation
Registered: 2011-05-23
Posts: 15,603

Re: Expectation

I got this for 2 bins:


“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

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#242 2013-04-01 02:16:01

bobbym
Administrator
From: Bumpkinland
Registered: 2009-04-12
Posts: 88,714

Re: Expectation

You mean:


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.

Offline

#243 2013-04-01 02:16:51

anonimnystefy
Real Member
From: The Foundation
Registered: 2011-05-23
Posts: 15,603

Re: Expectation

Well, it spit out the above for me...


“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

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#244 2013-04-01 02:18:14

bobbym
Administrator
From: Bumpkinland
Registered: 2009-04-12
Posts: 88,714

Re: Expectation

If it spits at you then you have to beat it into submission until it gives that answer.


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.

Offline

#245 2013-04-01 02:19:45

anonimnystefy
Real Member
From: The Foundation
Registered: 2011-05-23
Posts: 15,603

Re: Expectation

How did you get that answer?

I entered:

FindSequenceFunction[Table[f[2, j], {j, 1, 100}]]

“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

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#246 2013-04-01 02:23:37

bobbym
Administrator
From: Bumpkinland
Registered: 2009-04-12
Posts: 88,714

Re: Expectation

Underneath any answer should be the command bar.


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.

Offline

#247 2013-04-01 02:27:38

anonimnystefy
Real Member
From: The Foundation
Registered: 2011-05-23
Posts: 15,603

Re: Expectation

There is. I have plot, evaluate at a point, differentiate and integrate...


“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

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#248 2013-04-01 02:32:04

bobbym
Administrator
From: Bumpkinland
Registered: 2009-04-12
Posts: 88,714

Re: Expectation

You have more there than I do. But it changes, trying to figure what you want.

After you compute your answer, type in a new cell

FullSimplify[%]


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.

Offline

#249 2013-04-01 02:34:22

anonimnystefy
Real Member
From: The Foundation
Registered: 2011-05-23
Posts: 15,603

Re: Expectation

It's still the same...

What did you enter, exactly?


“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

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#250 2013-04-01 02:37:08

bobbym
Administrator
From: Bumpkinland
Registered: 2009-04-12
Posts: 88,714

Re: Expectation

First take the MatrixForm wrapper off the original code and change it to this:

ans=Table[Table[f[i,j],{i,2,2}],{j,1,15}]


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.

Offline

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