Four essential statistical functions for simulation in SAS

 


  • PDF function: This function is the probability density function. It returns the probability density at a given point for a variety of distributions. (For discrete distribution, the PDF function evaluates the probability mass function.)
  • CDF function: This function is the cumulative distribution function. The CDF returns the probability that an observation from the specified distribution is less than or equal to a particular value. For continuous distributions, this is the area under the PDF up to a certain point.
  • QUANTILE function: This function is closely related to the CDF function, but solves an inverse problem. Given a probability, P, it returns the smallest value, q, for which CDF(q) is greater than or equal to P.
  • RAND function: This function generates a random sample from a distribution. In SAS/IML software, use the RANDGEN subroutine, which fills up an entire matrix at once.

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