<P align=left><FONT face="Times New Roman">Why is it optimal to exercise an American put option when the stock falls low enough? Derive the condition for optimal early exercise of an American put option (FIND&nbsp;&nbsp;S). What do you think will happen when classes of put options treading on the exchange fulfill the condition you have derived?<o:p></o:p></FONT></P>
[此贴子已经被作者于2007-9-24 22:50:49编辑过]