This paper considers a class of nonparametric autoregression models with nonstationarity in the mean and then a class of nonparametric time series regression models with nonstationarity in both the conditional mean and conditional variance. For the nonparametric autoregression case, we propose a nonparametric unit–root test for the conditional mean. For the nonparametric time series regression ...

A test strategy consisting of a two-step application of a Lagrange Multiplier test was recently suggested as a device to reveal spatial nonstationarity, spurious spatial regression and spatial cointegration. The present paper generalises the test procedure by incorporating control for biased test values emerging from unobserved heteroscedasticity. Using Monte Carlo simulation, the behaviour of ...

In an infinite-horizon setting, Ferejohn and Page showed that Arrow’s axioms and stationarity lead to a dictatorship by the first generation. Packel strengthened this result by proving that no collective choice rule generating complete social preferences can satisfy unlimited domain, weak Pareto and stationarity. We prove that a domain restriction can be imposed and completeness can be dropped ...