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Topic: Help with probability&stat problem
Replies: 47   Last Post: Jun 16, 2007 4:32 AM

 Messages: [ Previous | Next ]
 Nick Posts: 690 Registered: 10/25/06
Re: Help with probability&stat problem
Posted: Jun 11, 2007 1:42 PM

"tutorny" <tutorny@gmail.com> wrote in message
>
>> Do you really think there is a 97% chance that
>> there will be a 30% drop out rate? Suppose I asked
>> you the probability that 100 of the students would
>> drop out. How would you calculate that? Do you think
>> that is a higher probability than only 30 students
>> dropping out?

>
> I am not entirely sure that I follow. 30 students out of 110 is 27%.
> So if a 20% rate is to be expected, isn't it feasible that a 27% rate
> is 96% likely?
>
> If I made the mistake there, it would be in making p = 0.20. So, I
> think what you are saying is that p should be = 0.80. But doing the
> calculations that way results in a nonsensical answer..

No, there is a 50% probability of there being a drop-out rate of greater
than 20%. At the extreme of a greater than 27% drop-out rate there is likely
to be a very small drop-out rate ie in the tail of the distribution.

Nick

Date Subject Author
6/11/07 tutorny
6/11/07 briggs@encompasserve.org
6/11/07 tutorny
6/11/07 Randy Poe
6/11/07 tutorny
6/11/07 Bruce Weaver
6/11/07 tutorny
6/11/07 Bruce Weaver
6/11/07 C6L1V@shaw.ca
6/11/07 Randy Poe
6/11/07 tutorny
6/11/07 Nick
6/11/07 Jack Tomsky
6/11/07 Luis A. Afonso
6/11/07 Jack Tomsky
6/11/07 Luis A. Afonso
6/11/07 Jack Tomsky
6/12/07 Luis A. Afonso
6/12/07 Jack Tomsky
6/12/07 Luis A. Afonso
6/12/07 Jack Tomsky
6/12/07 Luis A. Afonso
6/13/07 Jack Tomsky
6/13/07 Luis A. Afonso
6/13/07 Anon.
6/13/07 Jack Tomsky
6/13/07 Jack Tomsky
6/13/07 Luis A. Afonso
6/13/07 Jack Tomsky
6/13/07 Anon.
6/13/07 Luis A. Afonso
6/13/07 Jack Tomsky
6/13/07 Jack Tomsky
6/13/07 Anon.
6/13/07 Luis A. Afonso
6/13/07 Jack Tomsky
6/13/07 Luis A. Afonso
6/13/07 Jack Tomsky
6/14/07 Luis A. Afonso
6/14/07 Luis A. Afonso
6/14/07 Jack Tomsky
6/14/07 Luis A. Afonso
6/15/07 Luis A. Afonso
6/15/07 Jack Tomsky
6/15/07 Luis A. Afonso
6/15/07 Jack Tomsky
6/15/07 Luis A. Afonso
6/16/07 Luis A. Afonso