Economics 111.3 Winter 14

1. Economics 111.3 Winter 14 February 3rd, 2014 Lecture 10 Ch. 4 Ch. 6 (up to p. 138)

4. Total Revenue Test, or relations between seller’s Total Revenue and elasticity • If demand is elastic, a 1 percent price cut increases the quantity bought by more than 1 percent and the seller’s Total Revenueincreases. • If demand is inelastic, a 1 percent price cut increases quantity bought by less than 1 percent and the seller’s Total Revenue decreases.

5. If demand is unit elastic, a 1 percent price cut increases quantity bought by 1 percent and the seller’s Total Revenue does not change. P*Q= constant

6. Study question • The demand for a product is unit elastic throughout. If consumers purchase 8,000 units when the price is $5, how many units will they purchase if the price is $4?

7. Study Question: True or False • If the elasticity of demand curve for buckwheat is |1.25| at all prices higher than current price, we would expect that when bad weather reduces the size of the buckwheat crop, total revenue of buckwheat producers will fall

9. PRICE ELASTICITIES OF DEMAND A relationship is described as When its magnitude is Which means that Perfectly elastic or infinitely elastic Infinity The smallest possible increase in price causes an infinitely large decrease in quantity demanded. Elastic Less than infinity but greater than 1 The percent decrease in the quantity demanded exceeds the percent increase in price. Unit elastic 1 The percent decrease in the quantity demanded equals the percent increase in price. Inelastic Greater than zero but less than 1 The percentage decrease in the quantity demanded is less than the percent increase in price. Zero The quantity demanded is the same at all prices. Perfectly inelastic or completely inelastic

10. The cross elasticity of demand The cross elasticity of demand measures the responsiveness of the demand for a good to a change in the price of a substitute or complement good.

12. CROSS ELASTICITIES OF DEMAND Which means that A relationship is described as When its magnitude is Perfect substitutes Infinity The smallest possible increase in price of one good causes an infinitely large in the demand of the other good. Substitutes Positive, less than infinity If the price of one good increases, the quantity demanded of the other good also increases. Independent Zero The demand for one good remains constant, regardless of the price of the other good. Complements Less than zero The demand for one good decreases when the price of the other good increases.

13. Study question • Suppose the demand curve for a product is given by Q=10-2P+PS, where P is the price of the product and PS is the price of a substitute good. The price of the substitute good is $2.00. • Suppose P=$1.00 • What is the price elasticity of demand? • What is the cross-price elasticity of demand?

15. Income Elasticity of Demand • It measures how much the quantity demanded of a good responds to a change in consumers’ income. • It is computed as the percentage change in the quantity demanded divided by the percentage change in income.

16. Income elasticity of demand: some observationscity • Types of Goods • Normal Goods • Inferior Goods • Higher income raises the quantity demanded for normal goods but lowers the quantity demanded for inferior goods. • Goods consumers regard as necessities tend to be income inelastic • Examples include food, fuel, clothing, utilities, and medical services. • Goods consumers regard as luxuries tend to be income elastic. • Examples include sports cars, furs, and expensive foods.

19. Food

20. INCOME ELASTICITIES OF DEMAND: