To determine the variance in gross profit ... Companies can also look for ways of reducing waste and improving economies of scale. To calculate gross margin, subtract the cost of goods sold ...

This section discusses the computational details behind these tests. Note that the GLM procedure allows homogeneity of variance testing for simple one-way models only. Homogeneity of variance testing ...

When you have the average production of three machines, it is easy to calculate the average or mean production. You just add up the three means and divide by three. But what if I want the average ...