Second, there are important agency-related reasons why traders who have
just lost a great deal of money cannot immediately invest more in a country,
even if they believe that the expected returns are high. Shleifer and Vishny
(1997b) develop a model in which traders cannot persuade their "nancial
backers that they should be allowed to invest more, because having lost money
may indicate that the trader has bad judgment: `The seemingly perverse behavior
of taking money away from an arbitrageur after noise trader sentiment
deepens, i.e., precisely when his expected return is greatest, is a rational response
to the problem of trying to infer the arbitrageur's (unobserved) ability and future
opportunities jointly from past returnsa, (p. 41.) In reaction to a fall in asset
prices, "nancial backers might insist that the trader cut his or her position in
a country even further. Shleifer and Vishny (1997b) make this argument for
hedge funds involved in arbitrage, but the same argument can be applied to
large international banks lending to countries. As these investors pull their
money out, the exchange rate depreciates.