Question
What is discrete probability distribution? State its properties.
✓
Answer
Suppose, probability of a discrete random variable. $X$ is $p\left[X=x_i\right]=p\left(x_i\right)$, where $i=1,2,3, \ldots \ldots, n, p\left(x_i\right)>0$ and
$\sum_{i=1}^n p\left(x_i\right)=1$
then set of real values $\left\{p\left(x_1\right), p\left(x_2\right)\right.$, $\left.\mathrm{p}\left(\mathrm{x}_n\right)\right\}$ is called probability distribution of a discrete random variable $X$.
In tabular form it is written as follows :
Properties of discrete probability distribution :
- For each value $x$ of $X. p(x) > 0.$
- $\sum (x) = 1$
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