### Transform > Probability Distributions > Chi-Square

Calculates the probability densities, cumulative probabilities, and inverse cumulative probabilities for a chi-square distribution.

Use when random variables are greater than 0. If X has a standard normal distribution, X2 has a chi-square distribution, creating a commonly used sampling distribution. The shape of the chi-square distribution depends on the number of degrees of freedom.

### Dialog box items

•Source Column:

Enter the column you want to evaluate.

•Target Column:

Enter a storage column for the generated values. Leave blank to have VisualStat automatically name the target column.

•Statistics:

Choose from the following options:

oProbability density: Choose to calculate the probability densities.

oCumulative probability: Choose to compute the cumulative probabilities.

oInverse cumulative probability: Choose to compute the inverse of the cumulative probabilities.

•Distribution: Select the distribution for the variable.

•Deg Freedom: Enter the number of degrees of freedom you want to define the chi-square distribution.

### Example

Example of using the probability density function (pdf)

Probability Distributions

Web Resource: NIST e-Handbook of Statistical Methods, 2006 | Weisstein, Eric W., Wolfram MathWorld. | Wikipedia