April 20th, 2005, 6:47 pm
Reality isn't constrained by our ability to describe it. Period.True, but controlling or predicting reality does require the ability to describe the process.Let's try MBS. We are interested in pp rates, but also the configuration manifold. With a Poisson assumption, the hazards simply add to get the total pp rate. What's interesting is the changes to pos or neg correlation between individual mortages because of the financial environment.N