Some Theory Behind Chi-square Tests. example, then an example with two variables. For a single-variable chi-square, also known as a chi-square for goodness of fit, you can evaluate one of two types of hypotheses: you can follow up with the online Handbook of Biological Statistics. Back Click4Biology statistical analysis page, with great help for calculators and excel; Excellent Handbook of Biological Statistics from John MacDonald; Basic Statistical Tools, from the Natural Resources Management Department; And The Little Handbook of Statistical Practice is very useful. Sumanas statistics animations There is nothing magical about a sample size of 1000, it's just a nice round number that is well within the range where an exact test, chi-square test and G-test will give almost identical P values. Spreadsheets, web-page calculators, and SAS shouldn't have any problem doing an exact test on a sample size of 1000. The chi-square distribution (also called the chi-squared distribution) is a special case of the gamma distribution; A chi square distribution with n degrees of freedom is equal to a gamma distribution with a = n / 2 and b = 0.5 (or ? = 2).. Let's say you have a random sample taken from a normal distribution. To reference the Handbook please use a citation of the form: (Links to specific pages can also be referenced this way, if suitable.) A significant update was made to the Handbook April, 2012 The definition of what is meant by statistics and statistical analysis has changed considerably over the last few decades. Here are two contrasting definitions of what statistics is, from eminent professors in the field, some 60+ years apart: "Statistics is the branch of scientific method which deals with the data obtained by counting or Buy Handbook of Biological Statistics by John McDonald (Paperback) online at Lulu. Visit the Lulu Marketplace for product details, ratings, and reviews. Handbook of Biological Statistics, by John H. MacDonald, University