statistics

Probability Mass Function( P.M. f ):  )                             ( دالة الكتلة الاحتمالة

Let X be a Discrete Random Variables (d .v . r ) 

 A function  f  is a P. M .f if   f (x)= p (X=x) , and satisfy the following condition :

A ) f(x) 0 ,  x  X               B)

Note : 1- condition (A) shows the graph of f (x)  above of the X- axis  .

2- also .if A  S then   P  (x ) =