Math Is Fun Forum
  Discussion about math, puzzles, games and fun.   Useful symbols: √ ∞ ≠ ≤ ≥ ≈ ⇒ ∈ Δ θ ∴ ∑ ∫ π -

Login

Username

Password

Not registered yet?

#26 2013-04-07 01:02:23

Agnishom
Real Member
Award: Wink Sherlock

Offline

Re: Bayes' theorem problem

Got it,
Thanks bobbyM and gAr

So after all this isn't related to Bayes'?


'And fun? If maths is fun, then getting a tooth extraction is fun. A viral infection is fun. Rabies shots are fun.'
'God exists because Mathematics is consistent, and the devil exists because we cannot prove it'
'Who are you to judge everything?' -Alokananda

#27 2013-04-07 01:03:38

bobbym
Administrator

Offline

Re: Bayes' theorem problem

Why do you say that?


In mathematics, you don't understand things. You just get used to them.
I have the result, but I do not yet know how to get it.
All physicists, and a good many quite respectable mathematicians are contemptuous about proof.

#28 2013-04-07 01:05:36

Agnishom
Real Member
Award: Wink Sherlock

Offline

Re: Bayes' theorem problem

Because I don't see where you use it


'And fun? If maths is fun, then getting a tooth extraction is fun. A viral infection is fun. Rabies shots are fun.'
'God exists because Mathematics is consistent, and the devil exists because we cannot prove it'
'Who are you to judge everything?' -Alokananda

#29 2013-04-07 01:08:37

gAr
Star Member

Offline

Re: Bayes' theorem problem

Hi Agnishom,

It is related to Bayes', we just didn't write a formula for that!


"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."

#30 2013-04-07 01:09:59

bobbym
Administrator

Offline

Re: Bayes' theorem problem

There is a formula that covers what he did, it is called the extended form of Bayes theorem.


In mathematics, you don't understand things. You just get used to them.
I have the result, but I do not yet know how to get it.
All physicists, and a good many quite respectable mathematicians are contemptuous about proof.

#31 2013-04-07 01:21:45

Agnishom
Real Member
Award: Wink Sherlock

Offline

Re: Bayes' theorem problem

I tried to match that too.

p(a|b) = (p(b|a)*p(a))/((p(b|a)*p(a))+(p(b|not a)*p(not a))


'And fun? If maths is fun, then getting a tooth extraction is fun. A viral infection is fun. Rabies shots are fun.'
'God exists because Mathematics is consistent, and the devil exists because we cannot prove it'
'Who are you to judge everything?' -Alokananda

#32 2013-04-07 01:28:35

bobbym
Administrator

Offline

Re: Bayes' theorem problem

What you wrote is the extended form:



That has the form of his answer. That is what I was working on, trying to fill that in but I must have missed something.

His use of the tree is better, it lends itself to computation better.


In mathematics, you don't understand things. You just get used to them.
I have the result, but I do not yet know how to get it.
All physicists, and a good many quite respectable mathematicians are contemptuous about proof.

#33 2013-04-07 01:38:10

Agnishom
Real Member
Award: Wink Sherlock

Offline

Re: Bayes' theorem problem

Surely thats better.

But how do you use that formula?


'And fun? If maths is fun, then getting a tooth extraction is fun. A viral infection is fun. Rabies shots are fun.'
'God exists because Mathematics is consistent, and the devil exists because we cannot prove it'
'Who are you to judge everything?' -Alokananda

#34 2013-04-07 01:39:48

gAr
Star Member

Offline

Re: Bayes' theorem problem

I thought of something like:



and we have


"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."

#35 2013-04-07 01:41:11

bobbym
Administrator

Offline

Re: Bayes' theorem problem

Hi;

Look at his answer:



then look at the formula:



try replacing corresponding parts.

I did not see gAr's answer until I posted. He got the solution so he is the guy to ask.


In mathematics, you don't understand things. You just get used to them.
I have the result, but I do not yet know how to get it.
All physicists, and a good many quite respectable mathematicians are contemptuous about proof.

#36 2013-04-07 01:57:29

Agnishom
Real Member
Award: Wink Sherlock

Offline

Re: Bayes' theorem problem

Now in that part, what does A and B stand for?


'And fun? If maths is fun, then getting a tooth extraction is fun. A viral infection is fun. Rabies shots are fun.'
'God exists because Mathematics is consistent, and the devil exists because we cannot prove it'
'Who are you to judge everything?' -Alokananda

#37 2013-04-07 02:01:10

bobbym
Administrator

Offline

Re: Bayes' theorem problem

Hi Agnishom;

You are forgetting that I did not get the answer so I must not have filled that formula in correctly.


In mathematics, you don't understand things. You just get used to them.
I have the result, but I do not yet know how to get it.
All physicists, and a good many quite respectable mathematicians are contemptuous about proof.

#38 2013-04-07 02:04:45

Agnishom
Real Member
Award: Wink Sherlock

Offline

Re: Bayes' theorem problem

Okay, I am contended with the tree anyway. Next time I will think of one


'And fun? If maths is fun, then getting a tooth extraction is fun. A viral infection is fun. Rabies shots are fun.'
'God exists because Mathematics is consistent, and the devil exists because we cannot prove it'
'Who are you to judge everything?' -Alokananda

#39 2013-04-07 02:06:19

Agnishom
Real Member
Award: Wink Sherlock

Offline

Re: Bayes' theorem problem

gAr wrote:

I thought of something like:



and we have

Yes, yes, it seems more clear but how does it fit into the formula?

I mean how do you relate the calculation with it?

Last edited by Agnishom (2013-04-07 02:07:09)


'And fun? If maths is fun, then getting a tooth extraction is fun. A viral infection is fun. Rabies shots are fun.'
'God exists because Mathematics is consistent, and the devil exists because we cannot prove it'
'Who are you to judge everything?' -Alokananda

#40 2013-04-07 02:15:00

gAr
Star Member

Offline

Re: Bayes' theorem problem

Hi,


You can plug in the values now..


"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."

#41 2013-04-07 02:24:22

Agnishom
Real Member
Award: Wink Sherlock

Offline

Re: Bayes' theorem problem

Okay! Thanks


'And fun? If maths is fun, then getting a tooth extraction is fun. A viral infection is fun. Rabies shots are fun.'
'God exists because Mathematics is consistent, and the devil exists because we cannot prove it'
'Who are you to judge everything?' -Alokananda

#42 2013-04-07 02:47:12

bobbym
Administrator

Offline

Re: Bayes' theorem problem

Hi;

I found a couple of pages that agree with his approach and also calculate the number for you.


In mathematics, you don't understand things. You just get used to them.
I have the result, but I do not yet know how to get it.
All physicists, and a good many quite respectable mathematicians are contemptuous about proof.

#43 2013-04-07 02:49:12

Agnishom
Real Member
Award: Wink Sherlock

Offline

Re: Bayes' theorem problem

Webpages?


'And fun? If maths is fun, then getting a tooth extraction is fun. A viral infection is fun. Rabies shots are fun.'
'God exists because Mathematics is consistent, and the devil exists because we cannot prove it'
'Who are you to judge everything?' -Alokananda

#44 2013-04-07 02:50:43

bobbym
Administrator

Offline

Re: Bayes' theorem problem

Hi;

Yes, websites. Have not gone over them completely so I do not know how good their computations are.


In mathematics, you don't understand things. You just get used to them.
I have the result, but I do not yet know how to get it.
All physicists, and a good many quite respectable mathematicians are contemptuous about proof.

#45 2013-04-07 02:54:10

Agnishom
Real Member
Award: Wink Sherlock

Offline

Re: Bayes' theorem problem

May I have the link?


'And fun? If maths is fun, then getting a tooth extraction is fun. A viral infection is fun. Rabies shots are fun.'
'God exists because Mathematics is consistent, and the devil exists because we cannot prove it'
'Who are you to judge everything?' -Alokananda

#46 2013-04-07 02:07:04

bobbym
Administrator

Offline

Re: Bayes' theorem problem


In mathematics, you don't understand things. You just get used to them.
I have the result, but I do not yet know how to get it.
All physicists, and a good many quite respectable mathematicians are contemptuous about proof.

Board footer

Powered by FluxBB