Student's t-Distribution

http://demonstrations.wolfram.com/StudentsTDistribution/ The Wolfram Demonstrations Project contains thousands of free interactive visualizations, with new entries added daily. If Z is a standard normal random variable, Y is a chi-squared random variable with nu degrees of freedom, and Z and Y are independent, then Z/sqrtY / nu follows a t -distribution with nu degrees of freedom. Subtracting from the mean of a ran... Contributed by: Chris Boucher