COMM 215 Chapter Notes - Chapter 5-8: Confidence Interval, Simple Random Sample, Normal Distribution

• School: Concordia University
• Department: Commerce
• Course: COMM 215
• Professor: wissamnawfal

Document Summary

Random variables takes on different numerical values based on chance of some event. Discrete random variable: can only assume a finite number of values or infinite sequence of values. Continuous random variable: can assume uncountable infinite number of values. Expected value: mean of a probability distribution (average value when experiment that gives value for random variable is repeated over the long run) x = values of the discrete random variable. P(x) = probability of the random variable taking on the value of x. Standard deviation: measures spread, or dispersion, in a set of data and in the values of a random variable (cid:4666)(cid:4667)=(cid:4666)(cid:4667) E(x) = the expected value of x x = values of the discrete random variable. P(x) = probability of the random variable taking on the value x. Steps to computing the expected value and standard deviation: convert the frequency distribution into a probability distribution using relative frequency assessment method, compute the expected value, compute the standard deviation.