We consider the problem of predicting values of a random process or field satisfying a linear model y(x)=θ⊤f(x)+ε(x), where errors ε(x)are correlated. This is a common problem in kriging, where the case of discrete observations is standard. By focussing on the case of continuous...

The initial earnings of U.S. immigrants vary enormously by country of origin. Via three interrelated analyses, we show earnings convergence across source countries with time in the United States. Human-capital theory plausibly explains the inverse relationship between initial earnings and...

The initial earnings of U.S. immigrants vary enormously by country of origin. Via three interrelated analyses, we show earnings convergence across source countries with time in the United States. Human-capital theory plausibly explains the inverse relationship between initial earnings and...

We derive mean-unbiased estimators for the structural parameter in instrumental variables models with a single endogenous regressor where the sign of one or more first-stage coefficients is known. In the case with a single instrument, there is a unique nonrandomized unbiased estimator based on...