Probability and Statistics(3/35) Concept The cumulative distribution function F(x)is defined as the probability that the random variable X assumes a value less than or equal to a given x. This is calculated from the probability density function,as follows: F(x)=P(X≤x)=∫ft)d. @日济大学 TONGJI UNIVERSITY ➢ The cumulative distribution function F(x) is defined as the probability that the random variable X assumes a value less than or equal to a given x. This is calculated from the probability density function, as follows: Probability and Statistics(3/35) Concept