Discussion about math, puzzles, games and fun. Useful symbols: ÷ × ½ √ ∞ ≠ ≤ ≥ ≈ ⇒ ± ∈ Δ θ ∴ ∑ ∫ π -¹ ² ³ °

You are not logged in.

- Topics: Active | Unanswered

**gAr****Member**- Registered: 2011-01-09
- Posts: 3,479

I see.

For now, simulations for me too.

"Believe nothing, no matter where you read it, or who said it, no matter if I have said it, unless it agrees with your own reason and your own common sense" - Buddha?

"Data! Data! Data!" he cried impatiently. "I can't make bricks without clay."

Offline

**bobbym****Administrator**- From: Bumpkinland
- Registered: 2009-04-12
- Posts: 91,501

Your formula does look interesting though and I will play with it. Who knows, I might get lucky.

**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

**gAr****Member**- Registered: 2011-01-09
- Posts: 3,479

Yes, I'm also working on it.

"Believe nothing, no matter where you read it, or who said it, no matter if I have said it, unless it agrees with your own reason and your own common sense" - Buddha?

"Data! Data! Data!" he cried impatiently. "I can't make bricks without clay."

Offline

**gAr****Member**- Registered: 2011-01-09
- Posts: 3,479

Here's a joint distribution formula for four consecutive terms:

l_a : no. of cards less than a

s_b : number of cards selected having face value of b

nh : no. of positions available after placing the given 4 numbers

E.g.

Suppose we wanted to know the probability of sorted order to be 5 6 7 8, starting from 4th position:

We take the variables as:

5 5 5 8:

5 5 5 5: change s_d to s_a in the formula and

*Last edited by gAr (2014-02-04 23:03:45)*

"Believe nothing, no matter where you read it, or who said it, no matter if I have said it, unless it agrees with your own reason and your own common sense" - Buddha?

"Data! Data! Data!" he cried impatiently. "I can't make bricks without clay."

Offline

**bobbym****Administrator**- From: Bumpkinland
- Registered: 2009-04-12
- Posts: 91,501

Hi gAr;

I was busy doing some chores so I could not get to it till now. I will try it on some problems.

**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

**gAr****Member**- Registered: 2011-01-09
- Posts: 3,479

Hi,

Okay.

"Data! Data! Data!" he cried impatiently. "I can't make bricks without clay."

Offline

**bobbym****Administrator**- From: Bumpkinland
- Registered: 2009-04-12
- Posts: 91,501

Found the Kendall books but have not looked through them yet.

**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

**gAr****Member**- Registered: 2011-01-09
- Posts: 3,479

Hi,

Which book is that?

"Data! Data! Data!" he cried impatiently. "I can't make bricks without clay."

Offline

**bobbym****Administrator**- From: Bumpkinland
- Registered: 2009-04-12
- Posts: 91,501

The ones on Advanced Statistics. So far they are not very good.

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

Offline

**gAr****Member**- Registered: 2011-01-09
- Posts: 3,479

Okay.

"Data! Data! Data!" he cried impatiently. "I can't make bricks without clay."

Offline

**bobbym****Administrator**- From: Bumpkinland
- Registered: 2009-04-12
- Posts: 91,501

They claimed that the books were used for the writing of the probability routines in Maple. I got little out of them so far.

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

Offline

**gAr****Member**- Registered: 2011-01-09
- Posts: 3,479

I see.

"Data! Data! Data!" he cried impatiently. "I can't make bricks without clay."

Offline

**bobbym****Administrator**- From: Bumpkinland
- Registered: 2009-04-12
- Posts: 91,501

Hi gAr;

Suppose we wanted to know the probability of sorted order to be 5 6 7 8, starting from 4th position:

Does this mean x x x x 5 6 7 8, where x are cards?

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

Offline

**gAr****Member**- Registered: 2011-01-09
- Posts: 3,479

Hi,

... starting from 4th position

x x x 5 6 7 8 x

"Data! Data! Data!" he cried impatiently. "I can't make bricks without clay."

Offline

**bobbym****Administrator**- From: Bumpkinland
- Registered: 2009-04-12
- Posts: 91,501

Oh boy, I forgot how to count!

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

Offline

**gAr****Member**- Registered: 2011-01-09
- Posts: 3,479

Never mind, happens!

"Data! Data! Data!" he cried impatiently. "I can't make bricks without clay."

Offline

**bobbym****Administrator**- From: Bumpkinland
- Registered: 2009-04-12
- Posts: 91,501

Hi gAr;

For your first example of 5,6,7,8 ( x x x 5 6 7 8 x ) I am getting a simulation answer about 1 / 10 th as large as predicted. What are you getting?

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

Offline

**gAr****Member**- Registered: 2011-01-09
- Posts: 3,479

Hi,

My simulation answer is close: 0.0056

From the formula: 4162400 / C(52,8)

"Data! Data! Data!" he cried impatiently. "I can't make bricks without clay."

Offline

**bobbym****Administrator**- From: Bumpkinland
- Registered: 2009-04-12
- Posts: 91,501

That is very close to what I am getting with a simulation too. But the formula is not giving that answer. I will check that I have not made some error.

Okay, first problem checks out. On to the second one.

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

Offline

**gAr****Member**- Registered: 2011-01-09
- Posts: 3,479

You got it right?

"Data! Data! Data!" he cried impatiently. "I can't make bricks without clay."

Offline

**bobbym****Administrator**- From: Bumpkinland
- Registered: 2009-04-12
- Posts: 91,501

Hi gAr;

I finally got the same answer you did. Then I had connection problems for 5 hours finally got back online.

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

Offline

**gAr****Member**- Registered: 2011-01-09
- Posts: 3,479

Hi,

That's good!

"Data! Data! Data!" he cried impatiently. "I can't make bricks without clay."

Offline

**bobbym****Administrator**- From: Bumpkinland
- Registered: 2009-04-12
- Posts: 91,501

Hi gAr;

The second example checks out and on to the third...

Update:

The third example checks out! Ooooba oooba oooba, oooga ooog ooga! That means Wunderbar!

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

Offline

**eigenguy****Member**- Registered: 2014-03-18
- Posts: 78

Forgive me, please, for taking this thread all the way back to the beginning, and also if someone else has pointed this out in those thousands of posts I have despaired of hunting through to check:

bobbym wrote:

How would you judge this answer? And why?

The question itself and the replies given suggest this is wrong, but I would judge this answer correct. The following theorems are all easily proved:

The calculation shown follows from them.

"Having thus refreshed ourselves in the oasis of a proof, we now turn again into the desert of definitions." - Bröcker & Jänich

Offline

**bobbym****Administrator**- From: Bumpkinland
- Registered: 2009-04-12
- Posts: 91,501

Hi;

Did you see post #9 in this same thread?

Scientia and JFF are well grounded in questions like these.

Their complaint starts right here:

Courtesy of Wikipedia:

If f is a real-valued (or complex-valued) function, then taking the limit is compatible with the algebraic operations, provided the limits on the right sides of the equations below exist (the last identity only holds if the denominator is non-zero). This fact is often called the algebraic limit theorem.

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

Offline