We study the problem of portfolio insurance from the point of view of a fund manager, who guarantees to the investor that the portfolio value at maturity will be above a fixed threshold. If, at maturity, the portfolio value is below the guaranteed level, a third party will refund the investor up...

Close to half the California school districts let teachers choose whether to receive their salaries ten monthly payments or in twelve. Fisherine intertemporal maximization implies that they should choose ten payments and earn interest on their savings for their summer. But about half choose...