Geometrical distribution

• March 9th 2010, 01:23 AM
gralla55
Geometrical distribution
g(x; p) = p(1 − p)^(x-1), x = 1, 2, . . .
0, else

How can I find an expression for the cumulative probability distribution for this variable? That is, F(x) = P(X (less or equal to x)

Thanks!
• March 9th 2010, 09:05 AM
Plato
Quote:

Originally Posted by gralla55
g(x; p) = p(1 − p)^(x-1), x = 1, 2, . . .
0, else
How can I find an expression for the cumulative probability distribution for this variable? That is, F(x) = P(X (less or equal to x)

Is this what you are asking $\sum\limits_{x = 1}^n {p\left( {1 - p} \right)^{x - 1} } = 1 - \left( {1 - p} \right)^n ~?$