The cumulative distribution function (CDF) of 2 is the probability that the next roll will take a value less than or equal to 2 and is equal to 33.33% as there are two possible ways to get a 2 or below. The cumulative distribution function (CDF) of 1 is the probability that the next roll will take a value less than or equal to 1 and is equal to 16.667% as there is only one possible way to get a 1. The cumulative distribution function (CDF) is the probability that a random variable, say X, will take a value less than or equal to x.įor example, if you roll a die, the probability of obtaining 1, 2, 3, 4, 5, or 6 is 16.667% (=1/6). The Cumulative Distribution Function (CDF) Frequently seen patterns include the normal distribution, uniform distribution, binomial distribution, etc. Statisticians have observed that frequently used data occur in familiar patterns and so have sort to understand and define them. This description can be verbal, pictorial, in the form of an equation, or mathematically using specific parameters appropriate for different types of distributions. Or wonder why the probability density function does not apply to continuous distributions but is relevant for discrete distributions.Ī distribution in statistics or probability is a description of the data. Many students struggle to differentiate between probability density function (PDF) vs cumulative distribution function (CDF) when working on statistical problem sets.
Every MBA and CFA student will learn to work with distributions in their first statistics or quantitative analysis course.