It is shown that the limiting distribution of the augmented Dickey-Fuller (ADF) test under the null hypothesis of a unit root is valid under a very general set of assumptions that goes far beyond the linear AR (∞) process assumption typically imposed. In essence, all that is required is...

The problem of prediction is revisited with a view towards going beyond the typical nonparametric setting and reaching a fully model-free environment for predictive inference, i.e., point predictors and predictive intervals. A basic principle of model-free prediction is laid out based on the...

This paper proposes a nonparametric test for conditional independence that is easy to implement, yet powerful in the sense that it is consistent and achieves root-n local power. The test statistic is based on an estimator of the topological "distance" between restricted and unrestricted...

This paper examines a contractual settingwith unverifiable investment and a durable trading opportunity, in which trade can take place in any one of an infinite number of periods. The contractual setting features cross-investment, meaning that the seller’s investment affects the...

In the classic Arrow-Debreu model, the existence of money is not accommodated. However, using trading post market segmentation and requiring budget balance in each pair-wise transaction the model can converge to monetary equilibrium. Uniqueness of the common medium of exchange (commodity money)...

This paper examines a class of contractual relationships with specific investment, a non-durable trading opportunity, and renegotiation. FurtheringWatson’s (2007) line of analysis, trade actions are modeled as individual and trade-action-based option contracts are explored. Simple tools...

The paper develops the Öxed-smoothing asymptotics in a two-step GMM framework. Under this type of asymptotics, the weighting matrix in the second-step GMM criterion function converges weakly to a random matrix and the two-step GMM estimator is asymptotically mixed normal. Nevertheless, the Wald...

The federal government offers an array of tax-based aid student aid programs designed to lower the cost of postsecondary attendance. Many taxpayers are eligible for more than one program, yet they are limited to one program per student per year. Analyzing a unique panel dataset of individual...

We develop a new asymptotic theory for autocorrelation robust tests using a vector autoregressive (VAR) covariance matrix estimator. In contrast to the conventional asymptotics where the VAR order goes to infinity but at a slower rate than the sample size, wehave the VAR order grow at the...