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Binomial distribution

Discrete distribution. Describes situations where one of two outcomes can occur: eg ``success'' (1) or ``failure'' (0). Commonly used probability distribution in statistical sciences. The distribution function is described by equation 3.5:


 \begin{displaymath}P_r(X=x) = \left( \begin{array}{c} N\\ x \end{array} \right) p^x ( 1 - p )^{N-x}
\end{displaymath} (3.5)

where


\begin{displaymath}\left( \begin{array}{c} N\\ x \end{array} \right) = \frac{N!}{x! (N-x)!}
\end{displaymath}

N = number of trials and p = the probability for the event to occur.



 

David Stephenson
2000-09-02