Significant reductions in human visual gamma frequency by the gaba reuptake inhibitor tiagabine revealed by robust peak frequency estimation

The frequency of visual gamma oscillations is determined by both the neuronal excitation-inhibition balance and the time constants of GABAergic processes. The gamma peak frequency has been linked to sensory processing, cognitive function, cortical structure, and may have a genetic contribution. To disentangle the intricate relationship among these factors, accurate and reliable estimates of peak frequency are required. Here, a bootstrapping approach that provides estimates of peak frequency reliability, thereby increasing the robustness of the inferences made on this parameter was developed. The method using both simulated data and real data from two previous pharmacological MEG studies of visual gamma with alcohol and tiagabine was validated. In particular, the study by Muthukumaraswamy et al. [] (Neuropsychopharmacology 38(6):1105-1112), in which GABAergic enhancement by tiagabine had previously demonstrated a null effect on visual gamma oscillations, contrasting with strong evidence from both animal models and very recent human studies was re-evaluated. After improved peak frequency estimation and additional exclusion of unreliably measured data, it was found that the GABA reuptake inhibitor tiagabine did produce, as predicted, a marked decrease in visual gamma oscillation frequency. This result demonstrates the potential impact of objective approaches to data quality control, and provides additional translational evidence for the mechanisms of GABAergic transmission generating gamma oscillations in humans. Hum Brain Mapp, 2016. © 2016 Wiley Periodicals, Inc

Using information from singletons in fixed-effects estimation: xtfesing

In this article, we describe the xtfesing command. The command implements a generalized method of moments estimator that allows exploiting singleton information in fixed-effects panel-data regression as in Bruno, Magazzini, and Stampini (2020, Economics Letters 186: Article 108519)

Exploiting information from singletons in panel data analysis: A GMM approach

We propose a novel procedure, built within a Generalized Method of Moments framework, which exploits unpaired observations (singletons) to increase the efficiency of longitudinal fixed effect estimates. The approach allows increasing estimation efficiency, while properly tackling the bias due to unobserved time-invariant characteristics. We assess its properties by means of Monte Carlo simulations, and apply it to a traditional Total Factor Productivity regression, showing efficiency gains of approximately 8–9 percent

La competizione internazionale: caratteri di originalità delle imprese vicentine

Questo volume presenta i risultati di un'indagine empirica multidisciplinare sui fattori di crescita e di competitività delle imprese vicentine, sviluppata attraverso le chiavi di lettura della macro e della microeconomia, della strategia e della finanza aziendale. La ricerca ha riguardato oltre duemila aziende manifatturiere studiate lungo un periodo di cinque anni, con l'obiettivo di individuare i sentieri di crescita quantitativa perseguiti dalle imprese locali e di indagare quali tra di esse hanno abbinato alla crescita dimensionale uno sviluppo qualitativo interno dell'organizzazione aziendale. L'analisi condotta offre uno sguardo sul futuro del sistema locale: un futuro in cui entrano in scena nuovi paradigmi aziendali, che scardinano i luoghi comuni dei settori maturi e delle dimensioni ottimali, lasciando invece spazio alla "sostenibilità competitiva", intesa come la capacità delle imprese di affrontare la competizione e di reagire in modo tempestivo ai continui cambiamenti del mercato. Il volume costituisce la premessa per più ampie riflessioni sulla capacità di tenuta e di reazione del sistema produttivo locale, in un momento di trasformazioni profonde e repentine che minacciano nelle fondamenta la capacità di competere delle imprese, nonché di interi distretti e territori industriali