Probability Workbook For Dummies

Chapter 7

Dealing with Discrete Probability Distributions

IN THIS CHAPTER

Finding out what a probability distribution is

Getting the probability mass function

Calculating the mean, variance, and standard deviation

Pinpointing the discrete uniform distribution

In this chapter, you work with discrete random variables, which have either a finite list of possible values or a countably infinite list of possible values. You see how to combine the probabilities and the values to obtain the probability mass function (pmf). You also see how to calculate the mean, the variance, and the standard deviation of X. In addition, you work with the discrete uniform distribution, one of the more common and straightforward discrete distributions. These are all the basic ideas that go along with a random variable, in the discrete case.

Finding the Probability Distribution of a Discrete Random Variable

A probability is a function from the sample space, S, to the set of all possible real numbers in the interval [0, 1], denoted by capital letters like X, Y, and so on. For example, roll a die once and ...