A Simple Counterexample to Several Problems in the Theory of Asset Pricing
给出了两个严格正的局部鞅的例子，它们不是一致可积的，但它们的乘积却是一致可积鞅，该现象在不完全市场中普遍存在，对数学金融有应用。
We give an easy example of two strictly positive local martingales that fail to be uniformly integrable, but such that their product is a uniformly integrable martingale. The example simplifies an earlier example given by the second author. We give applications in mathematical finance and we show that the phenomenon is present in many incomplete markets.