This paper analyzes the asymptotic behavior of two types of so-called KPSS tests when a logarithm transformation has been applied spuriously to data that are themselves an integrated time series. Although a different limit distribution is obtained, the asymptotic convergence behavior of the KPSS statistic is reminiscent of that of integrated time series, and it is shown that the KPSS test canno...

The electronic structure of small fullerenes determined experimentally by anion photoelectron spectroscopy is compared with calculations. A huge mass signal and a large gap of 1.3 eV comparable to the gap of C70 have been found for C32, indicating that this cluster is the most stable fullerene below C60. Also C36, C44, and C50 exhibit large gaps and surprisingly high stabilities. The criteria f...

This paper proposes a simple direct testing procedure to distinguish a linear unit root process from a globally stationary three-regime self-exciting threshold autoregressive process. We derive the asymptotic null distribution of the Wald statistic, and show that it does not depend on unknown fixed threshold values. Monte Carlo evidence clearly indicates that the exponential average of the Wald...

This paper proposes a new methodology to build composite coincident and leading indexes. Based on a formal definition that requires that the first differences of the leading index is the best linear predictor of the first differences of the coincident index, it is shown that the notion of polynomial serial correlation common features can be used to build these composite variables. Concepts and ...

The Enders and Granger (1998) unit-root test against stationary alternatives with asymmetric adjustment is applied to the extended Nelson and Plosser dataset. The test rejects the unit-root null roughly as frequently as does the ADF test. JEL Classification C32, E32 * Correspondence: Philip Rothman Department of Economics East Carolina University Greenville, NC 27858 Phone: 252-328-6151 Fax: 25...

We develop a multivariate generalization of the Markov–switching GARCH model introduced by Haas, Mittnik, and Paolella (2004b) and derive its fourth– moment structure. An application to international stock markets illustrates the relevance of accounting for volatility regimes from both a statistical and economic perspective, including out–of–sample portfolio selection and computation of Value– ...

This article proposes a functional dynamic factor model for the evaluation of the impact of scalar– and curve–valued factors on the shapes of intraday price curves. The asymptotic theory leads to practically useful confidence intervals for the factor coefficients. The main findings pertain to the impact of the shapes of intraday oil futures on the shapes of intraday prices of blue chip stocks. ...

A panel of ex-ante forecasts of a single time series is modeled as a dynamic factor model, where the conditional expectation is the single unobserved factor. When applied to out-of-sample forecasting, this leads to combination forecasts that are based on methods other than OLS. These methods perform well in a Monte Carlo experiment. These methods are evaluated empirically in a panel of simulate...

We study the effects of government spending by using a structural, large dimensional, dynamic factor model. We find that the government spending shock is non-fundamental for the variables commonly used in the structural VAR literature, so that its impulse response functions cannot be consistently estimated by means of a VAR. Government spending raises both consumption and investment, with no ev...

Included here are two appendices. Appendix A has information on model priors, selected material on the data, and some details on computation. Appendix B contains an extended treatment of alternative measures of stress, and alternative measures of real activity, including how these measures compare to the base case model in terms of picking up the same state probabilities and, in some cases, qua...