국제통화위기와 투기적 공격

International Currency Crises and Speculative Attacks

The dynamic instability in the characteristics of the market exchange rate expectation structure is analyzed to be an important factor underlying speculative attacks and currency crises. When the extrapolative chartist forecasters dominate the fundamentalist forecasters in foreign exchange market, the overvaluation of a currency can be maintained for a certain period of time. During this period, even with cumulative current account deficits, the extrapolative expectation of the foreign exchange market supports the overvaluation of the currency. But at the turning point the deepening deterioration of real economic conditions and or the apprehension for the future of the exchange value of the currency following a currency crisis in the neighboring economy induce a sudden change in the dominant force among the chartist and the fundamentalist forecasters in foreign exchange market. Now the fundamentalist forecasters who believe that the exchange value of the currency is to drop dominate the market with the conversion of the former extrapolative chartist elements. This would lead to intensive speculative attacks and a currency crisis. The above arguments are suggested to be applicable to an explanation of the development of the Korean currency crisis in 1997.