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stuwii
21-08-2009, 10:21 AM
Need some resources linked to s2 for a2 maths. The poisson as an approximation to the binomial.

This page need be used only for those binomial situations in which n is very large and p is very small. For example: The null hypothesis holds that a certain genetic characteristic will express itself in p=.001 of the population. In a sample of n=3000 subjects, k=7 are observed to display the characteristic, whereas only np=3 are expected. On the null hypothesis, how likely is it that a rate this great or greater could occur by mere chance? Your computer would not be able to perform the factorial and exponential operations required for direct calculation (Exact Binomial Probability Calculator), and np<5 would preclude use the normal approximation (Binomial z-Ratio Calculator).

In cases of this sort, the appropriate binomial probabilities can be approximated by way of the Poisson probability function

TP(k out of n) = (e—np)(npk)

k!
where:
e = the base of the natural logarithms;
n = the number of opportunities for event x to occur;
k = the number of times that event x occurs or is stipulated to occur; and
p = the probability that event x will occur on any particular occasion;

Application of the Poisson function using these particular values of n, k, and p, will give the probability of getting exactly 7 instances in 3000 subjects. Applying it to all values of k equal to or greater than 7 will yield the probability of getting 7 or more instances in 3000 subjects, while applying it to all values of k equal to or smaller than 7 will give the probability of getting 7 or fewer instances in 3000 subjects. Note, however, that these results are only approximations of the true binomial probabilities, valid only in the degree that the binomial variance is a close approximation of the binomial mean.

To perform calculations of this type, enter the appropriate values for n, k, and p (the value of q=1—p will be calculated and entered automatically). Then click the 'Calculate' button. To enter a new set of values for n, k, and p, click the 'Reset' button. The value entered for p can be either a decimal fraction such as .001 or a common fraction such as 1/1000. Whenever possible, it is better to enter the common fraction rather than a rounded decimal fraction: e.g., 1/1050 rather than .00095.

If I don't get some stuff on this might not get to take A2 maths, need some questions as well

Retro_Link
21-08-2009, 11:07 AM
you can't tell but I'm trying to break the wtf moment by mooning you guys!

stuwii
21-08-2009, 11:12 AM
Is this the right stuff

Nicktendo
21-08-2009, 11:18 AM
Is this the right stuff

No that's just finished, Trisha is on now...

Ellmeister
21-08-2009, 11:19 AM
Genuine chocolate face?

EEVILMURRAY
21-08-2009, 11:27 AM
These may be old, but may help.
http://i31.photobucket.com/albums/c369/eevilmurray/Business/KxKa1p.jpg

http://i31.photobucket.com/albums/c369/eevilmurray/Business/elephantintheway.jpg

http://i31.photobucket.com/albums/c369/eevilmurray/Business/blondeanswer.gif

Roostophe
21-08-2009, 12:26 PM
*Tries to read the first paragraph*

...

*Tries to understand the first paragraph*

http://img193.imageshack.us/img193/3337/explodinghead3.jpg

I can't believe stuwii is doing a subject like this... :eek:

Nicktendo
21-08-2009, 12:41 PM
I can't believe stuwii is doing a subject like this... :eek:

Such beautiful irony. I thought the topic was about him, not... maths

dwarf gourami
21-08-2009, 01:51 PM
The real question you're asking is 'Where's Grunch?'.

Mr_Odwin
21-08-2009, 03:55 PM
So you are told to use the Poisson distribution as an approximation to the binomial. You are given all the stuf that you need by the look of it. The crux of the question seems to be

On the null hypothesis, how likely is it that a rate this great or greater could occur by mere chance?

It is talking about 7, or more, in 3000. One way to do this is to not work out the above question but to work out the probability of 6 or fewer. Then, one minus that is the same as the probability of 7 or more.

stuwii
21-08-2009, 04:03 PM
So you are told to use the Poisson distribution as an approximation to the binomial. You are given all the stuf that you need by the look of it. The crux of the question seems to be



It is talking about 7, or more, in 3000. One way to do this is to not work out the above question but to work out the probability of 6 or fewer. Then, one minus that is the same as the probability of 7 or more.

Seems the gist of the questions will be the operation of this formula in numerical and real life situations

Nintendohnut
21-08-2009, 04:51 PM
So.... is this to help you get back your lost FIFA save file, or what?

Shorty
21-08-2009, 04:58 PM
So.... is this to help you get back your lost FIFA save file, or what?
My post of the year.

Fierce_LiNk
21-08-2009, 05:06 PM
So.... is this to help you get back your lost FIFA save file, or what?

I never use the Thanks button, but I used it for that post. I was literally in tears and I swear that it felt like my insides were about to fall out.

On topic: Grunch and Odders. That is all ye need. Do you need to know this stuff before you take A2? Or are you doing it now? I was a little confused reading your wall of headache.

EEVILMURRAY
21-08-2009, 05:07 PM
So.... is this to help you get back your lost FIFA save file, or what?
Don't be stupid. All those fuckers play Pro Evo now.

chairdriver
21-08-2009, 05:14 PM
I would help, but I systematically erased all memories I had of S2 from my brain.

Statistics kills maths.

mcj metroid
21-08-2009, 07:51 PM
Need some resources linked to s2 for a2 maths. The poisson as an approximation to the binomial.

This page need be used only for those binomial situations in which n is very large and p is very small. For example: The null hypothesis holds that a certain genetic characteristic will express itself in p=.001 of the population. In a sample of n=3000 subjects, k=7 are observed to display the characteristic, whereas only np=3 are expected. On the null hypothesis, how likely is it that a rate this great or greater could occur by mere chance? Your computer would not be able to perform the factorial and exponential operations required for direct calculation (Exact Binomial Probability Calculator), and np<5 would preclude use the normal approximation (Binomial z-Ratio Calculator).

In cases of this sort, the appropriate binomial probabilities can be approximated by way of the Poisson probability function

TP(k out of n) = (e—np)(npk)

k!
where:
e = the base of the natural logarithms;
n = the number of opportunities for event x to occur;
k = the number of times that event x occurs or is stipulated to occur; and
p = the probability that event x will occur on any particular occasion;

Application of the Poisson function using these particular values of n, k, and p, will give the probability of getting exactly 7 instances in 3000 subjects. Applying it to all values of k equal to or greater than 7 will yield the probability of getting 7 or more instances in 3000 subjects, while applying it to all values of k equal to or smaller than 7 will give the probability of getting 7 or fewer instances in 3000 subjects. Note, however, that these results are only approximations of the true binomial probabilities, valid only in the degree that the binomial variance is a close approximation of the binomial mean.

To perform calculations of this type, enter the appropriate values for n, k, and p (the value of q=1—p will be calculated and entered automatically). Then click the 'Calculate' button. To enter a new set of values for n, k, and p, click the 'Reset' button. The value entered for p can be either a decimal fraction such as .001 or a common fraction such as 1/1000. Whenever possible, it is better to enter the common fraction rather than a rounded decimal fraction: e.g., 1/1050 rather than .00095.

If I don't get some stuff on this might not get to take A2 maths, need some questions as well
jesus it's like reading an edge review

ReZourceman
21-08-2009, 08:00 PM
Genuine help needed

Well, admitting it is the hardest step.

Tellyn
21-08-2009, 08:03 PM
I think I just used up all my "thanks" on this thread.

S.C.G
21-08-2009, 08:18 PM
I think I just used up all my "thanks" on this thread.

Me too. :heh:

...

we need a 'me too' button... >.>

Mr_Odwin
21-08-2009, 08:20 PM
I would help, but I systematically erased all memories I had of S2 from my brain.

Statistics kills maths.

*Is offended.*

Probability/Statistics is just as beautiful as other fields in mathematics. It's not all hypothesis testing.

S.C.G
21-08-2009, 08:25 PM
http://abstrusegoose.com/strips/fun_with_statistics2.PNG

Paj!
21-08-2009, 08:33 PM
http://abstrusegoose.com/strips/fun_with_statistics2.PNG

I loved. :heart:

EEVILMURRAY
22-08-2009, 12:16 AM
jesus it's like reading an edge review
True that. They're so unneedingly technically sounding.

Iun
22-08-2009, 01:29 AM
The real heart of the problem is this: How is this going to get you laid?

I have a similar question:

If x = y with a remaining factor of 3.7 - the cost of chicken pi, then what is z when v = 7z-underpants x 3yx?

The correct answer is, you're going home alone, Maths Boy.

EEVILMURRAY
22-08-2009, 12:14 PM
These pictures prove, that maths can indeed answer every question.

The real heart of the problem is this: How is this going to get you laid?
http://i31.photobucket.com/albums/c369/eevilmurray/Business/n12812888_31421406_6941.jpg
I have a similar question:

If x = y with a remaining factor of 3.7 - the cost of chicken pi, then what is z when v = 7z-underpants x 3yx?
http://i31.photobucket.com/albums/c369/eevilmurray/Business/349_ohdear.jpg
The correct answer is, you're going home alone, Maths Boy.

http://i31.photobucket.com/albums/c369/eevilmurray/Business/ohdear2.jpg


:blank:

Ish.