STAT 213 Lecture Notes - Lecture 20: Random Variable

• School: University of Calgary
• Department: Statistics
• Course: STAT 213
• Professor: Anatoliy Swishchuk

Document Summary

A random variable is a variable whose value is a numerical outcome of a random phenomenon. Let x be the number of heads when we toss a coin four times. X = 2 if outcome is htth; x = 1 if outcome is ttth. Thus, the possible values of x are 0, 1, 2, 3, 4. A discrete random variable x has a nite number4 of possible values. The probability distribution of x lists the values and their probabilities: The probabilities pi must satisfy two requirements: 0 pi 1, p1 + p2 + + pk = 1. How to nd the probability of any event: add the probabilities pi of the particular values xi that make up the event. 2 g n i t n u o c c. 0 y t i l i b a b o r. 3 s i e d a r g r e t t e b r o.