OMIS 2010 Chapter Notes - Chapter 15: Null Hypothesis, Standard Deviation, Contingency Table
Document Summary
Applied to multinomial experiment; generalization of a binomial experiment. In multinomial experiment: there are two or more possible outcomes per trial. We obtain set of observed frequencies f1, f2 , fk where fi is observed frequency of outcomes falling into cell i, for i = 1, 2, . Use observed frequencies to draw inferences about cell probabilities. If observed and expected frequencies are different, we conclude that null hypothesis is false. Goodness of fit test: measures similarity of expected and observed frequencies. Sampling distribution is approx chi squared with v = k 1, degrees of freedom. Actual sampling distribution of test statistic defined is discrete, but it can be approximated if sample size is large. Rule of 5: sample size must be large enough so that expected value for each cell must be 5 or more, when necessary, cells should be combined to satisfy this condition. Factors that identify chi-squared goodness of fit test.