We investigate confidence intervals and inference for the instrumental variables model with weak instruments. Wald-based confidence intervals perform poorly in that the probability they reject the null is far greater than their nominal size. In the worst case, Wald-based confidence intervals...

It is now well known that standard asymptotic inference techniques for instrumental variable estimation perform very poorly in the presence of weak instruments. Specifically, standard asymptotic techniques give spuriously small standard errors, leading investigators to accept apparently tight...

For a process with stationary first differences necessary and sufficient conditions for the variance of the process to be unbounded are given. An example shows that the variance of an integrated process -- while being unbounded -- need not diverge to infinity. Sufficient conditions for the...

We develop a simple robust test for the presence of continuous and discontinuous (jump) com­ponents in the price of an asset underlying an option. Our test examines the prices of at­the­money and out­of­the­money options as the option maturity approaches zero. We show that these prices...

Using nonlinear unit root tests developed by Kapetanios et al. (2003), we find strong evidence that the Consumer Price Index (CPI) and Wholesale Price Index (WPI) based Malaysian Ringgit – U.S. Dollar (MYR/USD) real exchange rates are nonlinear stationary, implying that MYR/USD nominal...

Using nonlinear unit root tests developed by Kapetanios et al. (2003), we find strong evidence that the Consumer Price Index (CPI) and Wholesale Price Index (WPI) based Malaysian Ringgit – U.S. Dollar (MYR/USD) real exchange rates are nonlinear stationary, implying that MYR/USD nominal...

In a dataset of weekly observations over the period since 1990, the discount on UK closed-end mutual funds is shown to be nonstationary, but reverting to a nonzero long run mean. Although the long run discount could be explained by factors like management expenses etc., its short run...

SURGAT is a RATS menu-driven program to help in the analysis of the seasonal component and the trend of a (quarterly, monthly or annual) time series. Once the series is selected, a set of simple transformations may be applied: log, regular difference, seasonal difference, regular+seasonal...