The chi-square test of independence is based on the compilation of normal approximations, and hence assumes expected cell counts to be greater than or equal to 5. With a continuous outcome, descriptive statistics are based on sums and averages. An independent t test or analysis of variance. A t test can be used via the regression model. A chi-square test, as described in this chapter.
Data come from a survey of smoking and socioeconomic status.
Five socioeconomic status groups are considered, with group 1 representing the lowest SES and group 5 representing the highest. By hand, calculate table of expected value. Using the Web calculator, test the hypothesis of no association. State the null and alternative hypotheses. Report the chi-square statistic, its degrees of freedom, and the total sample size, using the suggested APA format.