We present a standard model of financial innovation, in which intermediaries engineer securities with cash flows that investors seek, but modify two assumptions. First, investors (and possibly intermediaries) neglect certain unlikely risks. Second, investors demand securities with safe cash...

We model a financial market in which investor beliefs are shaped by representativeness. Investors overreact to a series of good news, because such a series is representative of a good state. A few bad news do not change investor minds because the good state is still representative, but enough...

We document two new facts about the distributions of answers in famous statistical problems: they are i) multi-modal and ii) unstable with respect to irrelevant changes in the problem. We offer a model in which, when solving a problem, people represent each hypothesis by attending "bottom up" to...