18-Discussion Questions Solutions - Lecture 18 Price Discrimination(I Suggested questions and exercises(Pindyck and Rubinfeld Ch.10 Questions 5 7 11

Lecture 18: Price Discrimination (I) Suggested questions and exercises (Pindyck and Rubinfeld, Ch.10). Questions: 5, 7, 11 Exercises: 1, 4, 5, 8 Additional Discussion Question (Based on Past Midterms and Finals). QUESTIONS 5. Show why optimal, third-degree price discrimination requires that marginal revenue for each group of consumers equals marginal cost. Use this condition to explain how a firm should change its prices and total output if the demand curve for one group of consumers shifted outward, so that marginal revenue for that group increased. We know that firms maximize profits by choosing output so marginal revenue is equal to marginal cost. If MR for one market is greater than MC , then the firm should increase sales to maximize profit, thus lowering the price on the last unit and raising the cost of producing the last unit. Similarly, if MR for one market is less than MC , the firm should decrease sales to maximize profit, thereby raising the price on the last unit and lowering the cost of producing the last unit. By equating MR and MC in each market, marginal revenue is equal in all markets. If the quantity demanded increased, the marginal revenue at each price would also increase. If MR = MC before the demand shift, MR would be greater than MC after the demand shift. To lower MR and raise MC , the producer should increase sales to this market by lowering price, thus increasing output. This increase in output would increase MC of the last unit sold. To maximize profit, the producer must increase the MR on units sold in other markets, i.e., increase price in these other markets. The firm shifts sales to the market experiencing the increase in demand and away from other markets. 7. How is peak-load pricing a form of price discrimination? Can it make consumers better off? Give an example. Price discrimination involves separating customers into distinct markets. There are several ways of segmenting markets: by customer characteristics, by geography, and by time. In peak-load pricing, sellers charge different prices to customers at different times. When there is a higher quantity demanded at each price, a higher price is charged. Peak-load pricing can increase total consumer surplus by charging a lower price to customers with elasticities greater than the average elasticity of the market as a whole. Most telephone companies charge a different price during normal business hours, evening hours, and night and weekend hours. Callers with more elastic demand wait until the period when the charge is closest to their reservation price.