International Economics
Download 7.1 Mb. Pdf ko'rish
|
Dominick-Salvatore-International-Economics
Problem From Figure 16.7, calculate the U.S. terms of trade before and after the 20 percent
depreciation or devaluation of the dollar. How do your results compare with those obtained in Section 16.3? Salvatore c16.tex V2 - 10/22/2012 9:19 A.M. Page 534 534 The Price Adjustment Mechanism with Flexible and Fixed Exchange Rates A16.2 Derivation of the Marshall–Lerner Condition We now derive mathematically the Marshall–Lerner condition that the sum of the elasticities of the demand for imports and the demand for exports must exceed 1 for the foreign exchange market to be stable. This condition holds when the supply curves of imports and exports are infinitely elastic, or horizontal. To derive the Marshall–Lerner condition mathematically, let: P X and P M = foreign currency price of exports and imports, respectively Q X and Q M = the quality of exports and imports, respectively V X and V M = the foreign currency value of exports and imports, respectively Then the trade balance (B) is B = V X − V M = Q X · P X − P M · Q M (16A-1) For a small devaluation, the change in the trade balance (dB ) is dB = P X · dQ X + Q X · dP X − (P M · dQ M + Q M · dP M ) (16A-2) This was obtained by the product rule of differentials (duv = v·du + u·dv). Since S M is horizontal, P M does not change (i.e., dP M = 0) with a depreciation or devaluation of the dollar, so that the last term in Equation (16A-2) drops out. By then rearranging the first and third terms, we get dB = dQ X · P X + Q X · dP x − dQ M · P M (16A-3) We now define Equation (16A-3) in terms of price elasticities. The price elasticity of the demand for exports (n X ) measures the percentage change in Q X for a given percentage change in P X . That is, n X = − dQ X Q X ÷ dP X P X = dQ X Q X ÷ k P X P X = dQ X · P X Q X · k · P X (16A-4) where k = –dP X /P X (the percentage of depreciation or devaluation of the dollar). Similarly, the coefficient of price elasticity of the demand for imports (n M ) is n M = − dQ M Q M − dP M P M = dQ M · P M Download 7.1 Mb. Do'stlaringiz bilan baham: |
Ma'lumotlar bazasi mualliflik huquqi bilan himoyalangan ©fayllar.org 2024
ma'muriyatiga murojaat qiling
ma'muriyatiga murojaat qiling