The authors demonstrate that most textbooks are ambiguous at best in their treatment of cross-price and income elasticity of demand. There is also no discussion of what initiates a price increase in discussions of substitutes and complements in the textbooks examined. The authors offer a remedy...

The burden of taxation is usually discussed in terms of elasticity of demand and supply. We show here that, at least for many students, merely using the slopes of demand and supply to yield the same conclusions will be more intuitively satisfying