Asymptotic null distributions of stationarity and nonstationarity

The purpose of this paper is to investigate the asymptotic null distribution of stationarity and nonstationarity tests when the distribution of the error term belongs to the normal domain of attraction of a stable law in any finite sample but the error term is an i.i.d. process with finite variance as T " 1. This local-to-finite variance setup is helpful to highlight the behavior of test statistics under the null hypothesis in the borderline or near borderline cases between finite and infinite variance and to assess the robustness of these test statistics to small departures from the standard finite variance context. From an empirical point of view, our analysis can be useful in settings where the (non)-existence of the (second) moments is not clear-cut, such as, for example, in the analysis of financial time series. A Monte Carlo simulation study is performed to improve our understanding of the practical implications of the limi theory we develop. The main purpose of the simulation experiment is to assess the size distortion of the unit root and stationarity tests under investigation.Stable distributions, unit root tests, stationarity tests, asymptotic distributions,local-to-finite variance, size distortion

The Fragility of the KPSS Stationarity Test

Stationarity tests exhibit extreme size distortions if the observable process is stationary yet highly persistent. In this paper we provide a theoretical explanation for the size distortion of the KPSS test for DGPs with a broad range of first order autocorrelation coefficient. Considering a near-integrated, nearly stationary process we show that the asymptotic distribution of the test contains an additional term, which can potentially explain the amount of size distortion documented in previous simulation studies.KPSS stationarity test, size distortion, nearly white noise nearly integrated model

The power of unit root tests under local-to-finite variance errors

We study the power of four popular unit root tests in the presence of a local-to-finite variance DGP. We characterize the asymptotic distribution of these tests under a sequence of local alternatives, considering both stationary and explosive ones . We supplement the theoretical analysis with a small simulation study to assess the finite sample power of the tests. Our results suggest that the finite sample power is affected by the $alpha$-stable component for low values of $alpha$ and that, in the presence of this component, the DW test has the highest power under stationary alternatives. We also document a strange behavior of the $DW$ test which, under the explosive alternative, suddenly falls from 1 to zero for very small changes in the autoregressive parameter suggesting a discontinuity in the power function of the $DW$ test

MCMC Bayesian Estimation of a Skew-GED Stochastic Volatily Model

In this paper we present a stochastic volatility model assuming that the return shock has a Skew-GED distribution. This allows a parsimonious yet flexible treatment of asymmetry and heavy tails in the conditional distribution of returns. The Skew-GED distribution nests both the GED, the Skew-normal and the normal densities as special cases so that specification tests are easily performed. Inference is conducted under a Bayesian framework using Markov Chain MonteCarlo methods for computing the posterior distributions of the parameters. More precisely, our Gibbs-MH updating scheme makes use of the Delayed Rejection Metropolis-Hastings methodology as proposed by Tierney and Mira (1999), and of Adaptive-Rejection Metropolis sampling. We apply this methodology to a data set of daily and weekly exchange rates. Our results suggest that daily returns are mostly symmetric with fat-tailed distributions while weekly returns exhibit both significant asymmetry and fat tails.Stochastic volatility, Markov Chain MonteCarlo, Skewness, Heavy tails, Bayesian inference, Metropolis-Hastings sampling

Happiness and Tax Morale: an Empirical Analysis

This paper presents empirical evidence that \tax morale" - taxpayers' intrinsic motivation to pay taxes - constitutes a new determinant of happiness, even after controlling for several demographic and socioeconomic factors. Using data on Italian households for 2004, we assess the strength of tax morale by relying on single items as well as composite multi-item indices. Our main result that scal honesty generates a higher hedonic payo than cheating is in line with Harbaugh et al. (2007)'s neuroeconomic nding. Further, it sheds light on the well-known \puzzle of compliance", that is the fact that many individuals pay taxes even when expected penalty and audit probability are extremely low: tax compliance is less puzzling once we show that not only it is materially costly, but also provides sizeable non-pecuniary benets that make it rewarding in itself.Happiness, Tax Morale, Tax Compliance

L’episodio dell’Annunciazione (Lc. 1:26-38) nei tituli historiarum tardoantichi: Ambrogio, Prudenzio, Pseudo-Claudiano

Il presente contributo prende in esame i tituli dedicati all’episodio dell’Annunciazione (Lc. 1:26-38) di Ambrogio (tituli III [18]), Prudenzio (ditt. XXV, 97-100) e dell’anonimo autore del poemetto intitolato Miracula Christi (Ps. Claud. carm. min. app. 21 = AL 879 R.2, 1-2). Dopo una rapida disamina delle caratteristiche del (sotto-) genere dei tituli historiarum a tema biblico della tarda antichità latina, si procederà ad un commento dettagliato e ad un confronto degli epigrammi dedicati all’annuncio alla Vergine, prestando attenzione sia agli aspetti letterari (anche intertestuali) che alle implicazioni teologiche dei testi. I paralleli con l’iconografia di fine IV-inizio V sec. legittimano l’ipotesi che i tituli, più che fungere da supporto in praesentia per un referente figurativo preesistente, invitassero i lettori alla sua ‘costruzione’ e visualizzazione, sulla base della condivisa cultura visuale.The present contribution takes into account the tituli dedicated to the Annunciation (Lk. 1:26-38) by Ambrose (tituli III [18]), Prudentius (ditt. XXV, 97-100), and the anonymous author of the short poem Miracula Christi (Ps. Claud. carm. min. app. 21 = A.L. 879 R.2, 1-2). After a rapid survey on the main features of the literary (sub-)genre of the Late Antique tituli historiarum with biblical theme, the article provides a detailed commentary to the epigrams dedicated to the Announcement to the Virgin, devoting attention both to the literary (also intertextual) aspects as well as to the texts’ theological implications. The iconographic parallels from the end of the 4th/beginning of the 5th c. legitimize the hypothesis that the tituli, more than constituting a support in praesentia for a pre-existing pictorial referent, aimed to invite the readers in its ‘construction’ and visualization, on the base of a common visual culture

Money Illusion: Are Economists Different?

We carried out a survey among a large group of undergraduate students of different disciplines and different years to test whether the study of economics or scientific majors influences the degree by which people are affected by money illusion. We find significant differences between first-year students, suggesting the presence of a selection bias towards money illusion in humanities students and away from it in economics and science students. In addiction, comparing economics students of different years, we do not find evidence of a learning effect.Money illusion

Continuum-continuum coupling and polarization potentials for weakly bound system

We investigate the influence of couplings among continuum states in collisions of weakly bound nuclei. For this purpose, we compare cross sections for complete fusion, breakup and elastic scattering evaluated by continuum discretized coupled channel (CDCC) calculations, including and not including these couplings. In our study, we discuss this influence in terms of the polarization potentials that reproduce the elastic wave function of the coupled coupled channel method in single channel calculations. We find that the inclusion of couplings among the continuum states renders the real part of the polarization potential more repulsive, whereas it leads to weaker apsorption to the breakup channel. We show that the non-inclusion of continuum-continuum couplings in CDCC calculations may not lead to qualitative and quantitative wrong conclusions.Comment: 4 pages, 4 figures. Submitted to Phys. Rev.