300 likes | 543 Views
Lecture 2. Discrete Random Variables Section 2.1-2.4. Definition. Each observation of an experiment is a random variable . (e.g. X) The set of possible values of a random variable is called the range of a random variable. (e.g. S X ). A random variable can be a function of the observation.
E N D
Lecture 2 Discrete Random Variables Section 2.1-2.4
Definition • Each observation of an experiment is a random variable. (e.g. X) • The set of possible values of a random variable is called the range of a random variable. (e.g. SX)
A random variable can be a function of another random variable
English translation: {X=x} emphasizes the idea that there is a set of sample points s within S (the sample space) for which X(s)=x.
Families of Discrete Random Variables • Bernoulli Random Variable • Geometric Random Variable • Binomial Random Variable • Pascal Random Variable • Discrete Uniform Random Variable (Not Covered) • Poisson Random Variable
geometricdf(p,x) What is the probability that Y is greater than 3?
poissoncdf(alpha,x) What is the probability that the switching office receives more than 2 calls, but less than 10 calls?