ABSTRACT
So, in this chapter we will be concerned with investigations in which two categorical variables are recorded for a number of 'individuals’. Such data may be set out neatly in two-way contingency tables (you may wish to reread Section 3-5 before proceeding). Initially, we will try to decide whether the two variables are independent or whether they are associated, by performing a hypothesis test, for example, the Chi-squared (^ 2) test for independence.
