21. That fact, and the normal and chi-squared distributions given above, form the basis of calculations involving the quotient 22. This has approximately a chi-squared distribution with " k " & minus; 1 degrees of freedom. 23. Kleinberg has shown that the optimal clustering coefficient for this model is q = 2, or an inverse square distribution . 24. The primary reason that the chi-squared distribution is used extensively in hypothesis testing is its relationship to the normal distribution. 25. The atlas was the first to present grid-square distribution maps for all breeding birds at a Europe-wide level. 26. One might hope that the resulting test statistic would have approximately a chi-square distribution when the null hypothesis is true. 27. Has a chi-squared distribution with \ nu = n-1 degrees of freedom ( by Cochran's theorem ). 28. Pearson showed that the chi-squared distribution , the sum of multiple normal distributions, was such an approximation to the multinomial distribution 29. Other examples of unimodal distributions include Cauchy distribution, Student's t-distribution, chi-squared distribution and exponential distribution. 30. Specifically, the scaled inverse chi-squared distribution can be used as a conjugate prior for the variance parameter of a normal distribution.
