Hi

I am not really a Statistician even though I get to teach the subject. 
But I do enjoy playing with things, especially if I can find a way to 
do it with (dare I say it --) an electronic spreadsheet!

This question concerns a straightforward linear system of 
equations; there are n equations in n+1 unknowns.
I've  just had a go at solving AX=B   (for n=5 Matrices) for various 
values of P(X=0) constraining  solutions to obey 0<P(X=i)<1 for all i.

For n = 5, 
A turns out to be invertible and looks like
  -5  4  0  0  0  
   1  -5  4  0  0 
   0  1  -5  4  0 
   0  0  1  -5  4 
   1  1  1  1  1

B looks like
 -p(0)
 0
 0
 0
 1-p(0)

Use Exel to find the inverse, then premultiply B with A(inverse), 
using various p(0) values. For n=5 there are solutions availible, eg 
with p(0) = 0.5 then p(1) = 0.178954.. etc . I haven't thought about 
the general case yet.

> how do you solve a problem like this one?
> thanks in advance
> -------
> X is a chance variable such that X(omega)={1,2,3...,n}
> and for every i in {1,2,3...n}, 4P(X=i+2)=5P(X=i+1)-P(X=i)
> 
> find the breakdown of X.
> 
> 


Cheers
                          ------Martin/
>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>
Martin James McKenzie
BSc(hons), MA, MSc, CTT
Academic Staff Member(ASM)
Lecturer in Mathematics and Statistics
Department of Business Studies
The WAIKATO POLYTECHNIC
Private Bag HN3036
HAMILTON 
NEWZEALAND

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