Showing posts with label Exchange Rate. Show all posts
Showing posts with label Exchange Rate. Show all posts

Monday, March 23, 2009

Harvy: A Post Keynesian View of Exchange Rate Determination

HARVEY, JT. 1991. A Post Keynesian view of exchange rate determination. Journal of Post Keynesian Economics 14, no. 1.

There is much out there that has explored exchange rate determination, though not very well. The monetary approach tends not to perform very well. They are not broadly useful models, though they may apply in one situation.

"It is the contention of this author that elements of a theory that can successfully explain the determination of exchange prices under the flexible rate system can be developed from the writings of various Post Keynesian scholars. This paper is intended to provide a rough outline of that approach and to spur further refinement of the model" (61).

"Davidson has emphasized the role of changing expectations in an environment of uncertainty as the key to volatility" (63). "Most important is Schulmeister's contention that those creating the bulk of the demand for foreign exchange are not those needing liquidity for international merchandise trade and investment, but instead the bank trading desks themselves" (63).

There is a distinction between the short-term expectations and the medium-term expectations of investors.

Hopper: What Determines the Exchange Rate?

Hopper, GP. 1997. What Determines the Exchange Rate: Economic Factors or Market Sentiment? Business Review 5: 17-29.

"Readers of the financial press are familiar with the gyrations of the currency market. No matter which way currencies zig or zag, it seems there is always an analyst with a quotable, ready explanation. Either interest rates are rising faster than expected in some country, or the trade balance is up or down, or central banks are tightening or loosening their monetary policies. Whatever the explanations, the underlying belief is that exchange rates are affected by fundamental economic forces, such as money supplies, interest rates, real output levels or the trade balance, which, if well forecasted, give the forecaster an advantage in predicting the exchange rate" (17).

However, it doesn't seem like exchange rates are affected by short-term fundamentals. "Economists have found instead that the best forecast of the exchange rate, at least in the short run, is whatever it happens to be today" (17).

"In this article, we'll review exchange-rate economics, focusing on what is predictable and what isn't. We'll see that exchange rates seem to be influenced by market sentiment rather than by economic fundamentals, and we'll examine the practical implications of this fact...We'll also see that volatility of exchange rates and correlations between exchange rates are predictable, and we'll examine the implications for currency option pricing, risk management, and portfolio selection" (18).

Exchange rate is supposed to be determined by current levels of monetary supplies and country output. Exchange rates are determined by what amount of money can be exchanged for a similar good in a given country. The prices of those goods are determined mainly by money supply levels. If, for example, money supply raises in one country ceteris paribus, this will raise prices in that country and will make that currency exchange at a different rate with the rest of the world. The reason that overall output is taken into consideration is because, when output rises, ceteris paribus, prices will fall (there is more out there but the same amount of money to buy it) and the currency will appreciate against the world.

This is all incredibly problematic because it's an open system and fundamentals are not actually known. Also, the model is problematic because it assumes that price levels can move freely and that they are not "sticky" (19).

Other models: Dornbusch developed the overshooting model, "...in which the average level of prices is assumed to be fixed in the short run to reflect the real-world finding that many prices don't change frequently" (19). Portfolio Balance Model: "In this approach, the supply of and demand for foreign and domestic bonds, along with the supply of and demand for foreign and domestic money, determine the exchange rate" (19-20).

News about the fundamentals may be more informative than the fundamentals (20). This news would change exchange rates if it differed from market expectation.

The key: Market Sentiment Matters in exchange rate determination.