STAB22H3 Chapter Notes - Chapter 16: Random Variable, Standard Deviation, Covariance

• School: UTSC
• Department: Statistics
• Course: STAB22H3
• Professor: Srishta Chopra

Document Summary

Random variable: a numeric value based on the outcomes of the random event; denoted with a capital letter, for example x. Discrete random variable: a random variable for which we can list all the. Continuous random variable: a random variable for which we cannot list all the outcomes. Probability model: collection of all the possible values and the probabilities that they occur for the random variable. Expected value/ mean of a random variable is written as or e(x) Calculating the expected value of a (discrete) random variable: multiply each possible value by the probability that it occurs, and find the sum. Var (x) = (deviation1)2 + (deviation2)2 + . 2 = var (x) = (x - )2p (x) = sd (x) = (var (x)) Data does not shift if you add/ subtract a constant to the variance or standard deviation. E(x c) = e (x) c. Data does shift if you add/ subtract a constant to the mean.