Mathematica 9 is now available
THIS IS DOCUMENTATION FOR AN OBSOLETE PRODUCT.
SEE THE DOCUMENTATION CENTER FOR THE LATEST INFORMATION.
Mathematica > Data Manipulation > Statistics > Statistical Distributions > Continuous Statistical Distributions >
Mathematica > Mathematics and Algorithms > Statistics > Statistical Distributions > Continuous Statistical Distributions >

ChiSquareDistribution

ChiSquareDistribution[Nu]
represents a chi^2 distribution with Nu degrees of freedom.
  • The probability density for value x in a chi^2 distribution is proportional to x^(nu/2-1)ⅇ^(-x/2) for x>0, and is zero for x<0. »
  • For integer Nu, the chi^2 distribution with Nu degrees of freedom gives the distribution of sums of squares of Nu values sampled from a normal distribution.
The mean and variance of a chi^2 distribution:
Probability density function:
Generate a set of pseudorandom numbers that are chi^2 distributed:
Properties based on higher-order moments:
Third moment of a chi^2 distribution:
The 0.75 quantile of a chi^2 distribution with nu=8:
Compute the p-value for a chi^2 test with n degrees of freedom:
Plot the cumulative distribution function of the random variable:
A contour plot as both x and Nu are varied:
The probability density function integrates to unity:
Moments can be obtained from the characteristic function:
The square root of a chi^2 variable follows the ChiDistribution:
ChiSquareDistribution and InverseChiSquareDistribution have an inverse relationship:
ChiSquareDistribution is not defined when Nu is not a positive real number:
Substitution of invalid parameters into symbolic outputs gives results that are not meaningful:
New in 6
Ask a question about this page  |  Suggest an improvement  |  Leave a message for the team