This paper advances the theory and methodology of signal extraction by introducing asymptotic and finite sample formulas for optimal estimators of signals in nonstationary multivariate time series. Previous literature has considered only univariate or stationary models. However, in current...

We build a model of a financial intermediary, in the tradition of Diamond and Dybvig (1983), and show that allowing the intermediary to impose redemption fees or gates in a crisis--a form of suspension of convertibility--can lead to preemptive runs. In our model, a fraction of investors...