CSCI 3022 Lecture Notes - Lecture 12: Probability Distribution, Standard Normal Deviate, Normal Distribution
Document Summary
The normal distribution (aka, gaussian distribution) is probably the most important and widely used distribution in probability and statistics. Many populations have distributions well-approximated by a normal distribution. It"s very important to check that normal is a good approximation through! A continuous random variable x has a normal (or gaussian) distribution with parameters and if its probability density function is given by. We say x~n( , ) the standard normal distribution: the normal distribution with parameter values =0, =1. A standard normal variable is usually denoted z. Recall: the normal distribution does not have a closed form cumulative distribution function (cid:736) we use special notation to denote the pdf of the standard normal distribution: (z) = p(z (cid:15457) z) (cid:736) and usually we just look up values for (z) in a table. The standard normal distribution rarely occurs in real life. Instead, we take non- standard normal distributions, and standardize them using a simple transformation.