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## #101 2012-11-09 08:52:43

anonimnystefy
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### Re: Expectation

From the definition of expectation..

#### bobbym wrote:

Hi;

That is not right either. Actually, the problem is related to a CCP but we have not covered that yet.

What is CCP?

The limit operator is just an excuse for doing something you know you can't.
“It's the subject that nobody knows anything about that we can all talk about!” ― Richard Feynman
“A secret's worth depends on the people from whom it must be kept.” ― Carlos Ruiz Zafón

## #102 2012-11-09 08:54:55

bobbym

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### Re: Expectation

We have not come to it yet but we soon will. Do you know another way for the last problem?

In mathematics, you don't understand things. You just get used to them.
Probability is the most important concept in modern science, especially as nobody has the slightest notion what it means.
90% of mathematicians do not understand 90% of currently published mathematics.

## #103 2012-11-09 08:57:06

anonimnystefy
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### Re: Expectation

I do not.

The limit operator is just an excuse for doing something you know you can't.
“It's the subject that nobody knows anything about that we can all talk about!” ― Richard Feynman
“A secret's worth depends on the people from whom it must be kept.” ― Carlos Ruiz Zafón

## #104 2012-11-09 08:59:49

bobbym

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### Re: Expectation

Hi;

In mathematics, you don't understand things. You just get used to them.
Probability is the most important concept in modern science, especially as nobody has the slightest notion what it means.
90% of mathematicians do not understand 90% of currently published mathematics.

## #105 2012-11-09 09:01:49

anonimnystefy
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### Re: Expectation

#### anonimnystefy wrote:

From the definition of expectation..

#### bobbym wrote:

Hi;

That is not right either. Actually, the problem is related to a CCP but we have not covered that yet.

What is CCP?

Did you not see the first sentence of this post?

The limit operator is just an excuse for doing something you know you can't.
“It's the subject that nobody knows anything about that we can all talk about!” ― Richard Feynman
“A secret's worth depends on the people from whom it must be kept.” ― Carlos Ruiz Zafón

## #106 2012-11-09 09:02:55

bobbym

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### Re: Expectation

Yes, I did and I said we have not got to it yet. CCP is short for Coupon Collector Problem.

In mathematics, you don't understand things. You just get used to them.
Probability is the most important concept in modern science, especially as nobody has the slightest notion what it means.
90% of mathematicians do not understand 90% of currently published mathematics.

## #107 2012-11-09 09:08:34

anonimnystefy
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### Re: Expectation

No, I didn't mean that. The text before the quote is on its own. It is not conected to the rest of the post. It was an answer to your previously asked question.

The limit operator is just an excuse for doing something you know you can't.
“It's the subject that nobody knows anything about that we can all talk about!” ― Richard Feynman
“A secret's worth depends on the people from whom it must be kept.” ― Carlos Ruiz Zafón

## #108 2012-11-09 09:09:52

bobbym

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### Re: Expectation

I see, but I think I already answered the question with post #104.

In mathematics, you don't understand things. You just get used to them.
Probability is the most important concept in modern science, especially as nobody has the slightest notion what it means.
90% of mathematicians do not understand 90% of currently published mathematics.

## #109 2012-11-09 09:11:41

anonimnystefy
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### Re: Expectation

Last edited by anonimnystefy (2012-11-09 09:12:10)

The limit operator is just an excuse for doing something you know you can't.
“It's the subject that nobody knows anything about that we can all talk about!” ― Richard Feynman
“A secret's worth depends on the people from whom it must be kept.” ― Carlos Ruiz Zafón

## #110 2012-11-09 09:12:45

bobbym

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### Re: Expectation

Well then, when I asked for another way you should have posted it prior to post #104

In mathematics, you don't understand things. You just get used to them.
Probability is the most important concept in modern science, especially as nobody has the slightest notion what it means.
90% of mathematicians do not understand 90% of currently published mathematics.

## #111 2012-11-09 09:17:11

anonimnystefy
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### Re: Expectation

I did! It is in the first part of post #101!

The limit operator is just an excuse for doing something you know you can't.
“It's the subject that nobody knows anything about that we can all talk about!” ― Richard Feynman
“A secret's worth depends on the people from whom it must be kept.” ― Carlos Ruiz Zafón

## #112 2012-11-09 09:19:26

bobbym

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### Re: Expectation

Yes, I know but it is nice to see the formula actually in front of you...

In mathematics, you don't understand things. You just get used to them.
Probability is the most important concept in modern science, especially as nobody has the slightest notion what it means.
90% of mathematicians do not understand 90% of currently published mathematics.

## #113 2012-11-09 09:29:49

anonimnystefy
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### Re: Expectation

Do you have another problem?

The limit operator is just an excuse for doing something you know you can't.
“It's the subject that nobody knows anything about that we can all talk about!” ― Richard Feynman
“A secret's worth depends on the people from whom it must be kept.” ― Carlos Ruiz Zafón

## #114 2012-11-09 09:30:58

bobbym

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### Re: Expectation

I have many problems, social, psychological and math. Which do you want to try and solve?

In mathematics, you don't understand things. You just get used to them.
Probability is the most important concept in modern science, especially as nobody has the slightest notion what it means.
90% of mathematicians do not understand 90% of currently published mathematics.

## #115 2012-11-09 09:32:50

anonimnystefy
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### Re: Expectation

Let's try math first.

The limit operator is just an excuse for doing something you know you can't.
“It's the subject that nobody knows anything about that we can all talk about!” ― Richard Feynman
“A secret's worth depends on the people from whom it must be kept.” ― Carlos Ruiz Zafón

## #116 2012-11-09 09:35:27

bobbym

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### Re: Expectation

Okay.

What is the expected number of times a fair die must be rolled until all scores appear at least once?

In mathematics, you don't understand things. You just get used to them.
Probability is the most important concept in modern science, especially as nobody has the slightest notion what it means.
90% of mathematicians do not understand 90% of currently published mathematics.

## #117 2012-11-09 10:39:29

anonimnystefy
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### Re: Expectation

Hi bobbym

14.7?

The limit operator is just an excuse for doing something you know you can't.
“It's the subject that nobody knows anything about that we can all talk about!” ― Richard Feynman
“A secret's worth depends on the people from whom it must be kept.” ― Carlos Ruiz Zafón

## #118 2012-11-09 10:43:39

bobbym

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### Re: Expectation

Yes! Very good! Although it does not look like it that is a CCP.

In mathematics, you don't understand things. You just get used to them.
Probability is the most important concept in modern science, especially as nobody has the slightest notion what it means.
90% of mathematicians do not understand 90% of currently published mathematics.

## #119 2012-11-09 10:58:08

anonimnystefy
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### Re: Expectation

Oh, but it does look like a CCP.

Any more?

The limit operator is just an excuse for doing something you know you can't.
“It's the subject that nobody knows anything about that we can all talk about!” ― Richard Feynman
“A secret's worth depends on the people from whom it must be kept.” ― Carlos Ruiz Zafón

## #120 2012-11-09 11:04:51

bobbym

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### Re: Expectation

First, how did you solve the last one?

Just one or two more of these lightweight problems and we can move on to tougher ones.

In mathematics, you don't understand things. You just get used to them.
Probability is the most important concept in modern science, especially as nobody has the slightest notion what it means.
90% of mathematicians do not understand 90% of currently published mathematics.

## #121 2012-11-09 19:22:12

anonimnystefy
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### Re: Expectation

I solved it using absorbing Markov chains.

The limit operator is just an excuse for doing something you know you can't.
“It's the subject that nobody knows anything about that we can all talk about!” ― Richard Feynman
“A secret's worth depends on the people from whom it must be kept.” ― Carlos Ruiz Zafón

## #122 2012-11-09 20:02:33

bobbym

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### Re: Expectation

Hmmm, mind If I see it? Then I can show you another way.

In mathematics, you don't understand things. You just get used to them.
Probability is the most important concept in modern science, especially as nobody has the slightest notion what it means.
90% of mathematicians do not understand 90% of currently published mathematics.

## #123 2012-11-10 01:24:43

anonimnystefy
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### Re: Expectation

It's a pretty large one to do by hand.

(0,1,0,0,0,0,0)
(0,1/6,5/6,0,0,0,0)
(0,0,1/3,2/3,0,0,0)
(0,0,0,1/2,1/2,0,0)
(0,0,0,0,2/3,1/3,0)
(0,0,0,0,0,5/6,1/6)
(0,0,0,0,0,0,1)

Last edited by anonimnystefy (2012-11-10 01:25:14)

The limit operator is just an excuse for doing something you know you can't.
“It's the subject that nobody knows anything about that we can all talk about!” ― Richard Feynman
“A secret's worth depends on the people from whom it must be kept.” ― Carlos Ruiz Zafón

## #124 2012-11-10 01:48:51

bobbym

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### Re: Expectation

Hi;

You did forget the labels but here is another way.

The expected wait for all scores to appear = expected wait for one score +
expected wait for second score + ... + expected wait for sixth and final score.
The probabilities of these events are, respectively, 6/6, 5/6, 4/6, 3/6, 2/6, 1/6.
Therefore the expected wait for all scores to appear?

It's a pretty large one to do by hand.

No one but a lunatic would want to.

When you computed the answer you should have got a big surprise.

In mathematics, you don't understand things. You just get used to them.
Probability is the most important concept in modern science, especially as nobody has the slightest notion what it means.
90% of mathematicians do not understand 90% of currently published mathematics.

## #125 2012-11-10 04:45:09

anonimnystefy
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### Re: Expectation

Why 6/k?

Why should the anwser be a big surprise?

The limit operator is just an excuse for doing something you know you can't.
“It's the subject that nobody knows anything about that we can all talk about!” ― Richard Feynman
“A secret's worth depends on the people from whom it must be kept.” ― Carlos Ruiz Zafón