Chi-square distribution

In probability theory and statistics, the chi-square distribution (also chi-squared or   distribution) is one of the most widely used theoretical probability distributions. Chi-square distribution with  degrees of freedom is written as . It is a special case of gamma distribution.

Chi-square distribution is primarily used in statistical significance tests and confidence intervals. It is useful, because it is relatively easy to show that certain probability distributions come close to it, under certain conditions. One of these conditions is that the null hypothesis must be true. Another one is that the different random variables (or observations) must be independent of each other.

 Related pages 

 Chi-squared test

 References 

Other websites
Chi-Square Tutorial by Khan Academy

Category:Probability distributions