Suppose we want to classify defects found in furniture produced in a manufacturing plant according to (1) the type of defect and (2) the production shift. A total of 309 furniture defects were recorded as one of four types, A, B, C, or D. At the same time each piece of furniture was identified according to the production shift during which it was manufactured, 1st shift, 2nd shift, or 3rd shift. What degrees of freedom should be used to calculate a p-value in a Chi-Squared test for independence between the type of defect and production shift
