Statistics

[K.I.L.E.R]

BTW: This is not homework.
We never get homework from university or tafe.

It was last year since I've done statistics.
I also had the audacity to avoid studying for the subject and exam and still managed to pass.

 

[K.I.L.E.R]

4*4 = 16?

4 different ways to answer q1
4 different ways to answer q2

how many different ways to answer q1&q2?

 

[epicstruggle]

BTW: This is not homework.
We never get homework from university or tafe.

It was last year since I've done statistics.
I also had the audacity to avoid studying for the subject and exam and still managed to pass.

You seem to be living through the addage: Reap what you sow.

 

[Jabbah]

4*4 = 16?

Right 16 (4*4) ways to answer 2 questions. Now extend to 10 questions.

 

[Jabbah]

Now for the second part (if anyone is still reading the thread after all that!)

There are 2 answers I am thinking of, the one that makes more sense to me is P^(n-1) as opposed to P^2?

 

[K.I.L.E.R]

I used nPr as it made sense because you are selecting 1/4 options in exactly 8 questions, there is a probability of 3/4 to slip up.
P^(n-1) is right, I just used a quick Google hack to find the formula and it said n-2 so I put that it instead.

Now for the second part (if anyone is still reading the thread after all that!)

There are 2 answers I am thinking of, the one that makes more sense to me is P^(n-1) as opposed to P^2?

 

[Simon F]

Now for the second part (if anyone is still reading the thread after all that!)

There are 2 answers I am thinking of, the one that makes more sense to me is P^(n-1) as opposed to P^2?

The second question is more interesting but not too difficult...
Well, I need a break from the coding anyway...

You have 2 sets of answers, A and B, and you want to know what's the probability that B has exactly the same answers as A on 8 arbitrary questions and different on the remaining 2.

I'd say it's
10C8 * Number of Ways(of those 8 matching) * Number of ways of the 2 failing / Total Combinations

= 10C8 * (1^8) * (3^2) / 4^10=3.86x10^-4

 

[Jabbah]

Me goes and reads the second part of the question again Ooops missed that little 8 thing.

Edit:
If I wasnt about to go to the Lamb and Flag to get slaughtered for Easter I would work it out, oh well, maybe when I'm back at work next week :smile:

 

[K.I.L.E.R]

Is this any clearer?

There is a 10 question multiple choice test, with each question having 4 possible choices. The answers to the questions are not based on prior knowledge of the test material (like in a maths class for example). What I mean by this is that there is a 1/4 chance that a person will select a certain answer. There are no dummy answers that no one would select.

Now, the sample size is 2. That is, 2 people did the test and then compared answers, 8 of the questions where answered identically.

My question is: What is the statistical chance of this happening?

 

[PARANOiA]

I also had the audacity to avoid studying for the subject and exam and still managed to pass.

Doesn't it concern you that you want to try and make a living doing this? If your boss asks you to solve a problem, will you jump on B3D and make a squillion threads about it then, too?

 

[K.I.L.E.R]

I'm not making a living doing statistics.
I will avoid it as much as possible.
I'm doing things related to computer graphics.
Anyway my other threads weren't about stats.
I'm already reading my math book's linear algebra section from scratch.

Doesn't it concern you that you want to try and make a living doing this? If your boss asks you to solve a problem, will you jump on B3D and make a squillion threads about it then, too?