Endogenous Price Commitment, Sticky and Leadership Pricing: Evidence from the Italian Petrol Market

This article studies dynamic pricing strategies in the Italian gasoline market before and after the market leader unilaterally announced its commitment to adopt a sticky-pricing policy. Using daily Italian firm level prices and weekly average EU prices, we show that the effect of the new policy was twofold. First, it facilitated price alignment and coordination on price changes. After the policy change, the observed pricing pattern shifted from cost-based to sticky-leadership pricing. Second, using a dif-in-dif estimation and a synthetic control group, we show that the causal effect of the new policy was to significantly increase prices through sticky-leadership pricing. Our paper highlights the importance of price-commitment by a large firm in order to sustain (tacit) collusion

Wi-Fi Coexistence with Duty Cycled LTE-U

Coexistence of Wi-Fi and LTE-Unlicensed (LTE-U) technologies has drawn significant concern in industry. In this paper, we investigate the Wi-Fi performance in the presence of duty cycle based LTE-U transmission on the same channel. More specifically, one LTE-U cell and one Wi-Fi basic service set (BSS) coexist by allowing LTE-U devices transmit their signals only in predetermined duty cycles. Wi-Fi stations, on the other hand, simply contend the shared channel using the distributed coordination function (DCF) protocol without cooperation with the LTE-U system or prior knowledge about the duty cycle period or duty cycle of LTE-U transmission. We define the fairness of the above scheme as the difference between Wi-Fi performance loss ratio (considering a defined reference performance) and the LTE-U duty cycle (or function of LTE-U duty cycle). Depending on the interference to noise ratio (INR) being above or below -62dbm, we classify the LTE-U interference as strong or weak and establish mathematical models accordingly. The average throughput and average service time of Wi-Fi are both formulated as functions of Wi-Fi and LTE-U system parameters using probability theory. Lastly, we use the Monte Carlo analysis to demonstrate the fairness of Wi-Fi and LTE-U air time sharing

Scaling and multiscaling in financial series: a simple model

We propose a simple stochastic volatility model which is analytically tractable, very easy to simulate and which captures some relevant stylized facts of financial assets, including scaling properties. In particular, the model displays a crossover in the log-return distribution from power-law tails (small time) to a Gaussian behavior (large time), slow decay in the volatility autocorrelation and multiscaling of moments. Despite its few parameters, the model is able to fit several key features of the time series of financial indexes, such as the Dow Jones Industrial Average, with a remarkable accuracy.Comment: 32 pages, 5 figures. Substantial revision, following the referee's suggestions. Version to appear in Adv. in Appl. Proba

Effect of Hatha yoga on anxiety: a meta-analysis

OBJECTIVE: Some evidence suggests that Hatha yoga might be an effective practice to reduce anxiety. To examine the effect of Hatha yoga on anxiety, we conducted a meta-analysis of relevant studies extracted from PubMed, PsycINFO, the Cochrane Library, and manual searches. METHODS: The search identified 17 studies (11 waitlist controlled trials) totaling 501 participants who received Hatha yoga and who reported their levels of anxiety before and after the practice. We estimated the controlled and within-group random effects of the practice on anxiety. RESULTS: The pre-post within-group and controlled effect sizes were, Hedges' g = 0.44 and Hedges' g = 0.61, respectively. Treatment efficacy was positively associated with the total number of hours practiced. People with elevated levels of anxiety benefitted the most. Effect sizes were not moderated by study year, gender, presence of a medical disorder, or age. Although the quality of the studies was relatively low, the risk of study bias did not moderate the effect. CONCLUSIONS: Hatha yoga is a promising method for treating anxiety. However, more well-controlled studies are needed to compare the efficacy of Hatha yoga with other more established treatments and to understand its mechanism. This article is protected by copyright. All rights reserved.R01 AT007257 - NCCIH NIH HH

La Realtà Virtuale al servizio della Didattica

Alla fine degli anni ’50, il regista Morton Heilig, universalmente noto come padre della Realtà Virtuale, presentò al Mondo un prototipo denominato Sensorama. Oggi, a quasi 70 anni di distanza, il sogno di consentire pressoché a chiunque un’esperienza sensoriale che sia, al tempo stesso credibile e alternativa, sembra sul punto di avverarsi; grazie ad una tecnologia finalmente all’altezza delle intuizioni di Heilig, ma grazie anche agli enormi investimenti prodotti, in modo specifico, dall’industria videoludica. Tuttavia, ben oltre il contesto dell’Entertainment, le applicazioni potenziali della Realtà Virtuale sembrano poter attraversare gli ambiti più disparati, incidendo in modo particolarmente significativo nel campo dell’Educazione. Mentre, tra Stati Uniti e Oriente tecnologico, gran parte delle Università più prestigiose propongono non solo progetti sperimentali in VR, ma anche risultati significativi in termini di apprendimento, la questione da porre è la seguente: può un sistema, per lo più ideato e realizzato col fine ultimo di intrattenere, costituire la chiave di volta per una Rivoluzione Didattica di proporzioni globali

The role of psychotherapy in the treatment of acute mental disorders

This work is directed to further investigate the significant relevance of psychotherapy to better management of acute psychiatric disorders. Over the last years, there was impressive increase of the amount of psychiatric patients referred to emergency and in-patient treatment and such increase allmost resulted from subjects with acute emotional discontrol associated with affective, personality and stress related disorders. According to such change of the clinical scene of contemporary psychiatry, more attention and funding are needed in the field of acute treatment services and combined treatment innovation and research is become a major challenge for community psychiatry. A real progress in the field is not, however a simple matter of psychoterapy technology transference. While several recent studies suggest that well designed combined treatment is cost-effective in these patients, new nosographic, management and dynamic models are required for succesful development of new crisis intervention programs within general psychiatry service

L'importanza della corretta prevenzione in vista della road map europea 2050

Nella mia tesi ho descritto la situazione a energetica e ambientale attuale, le scelte dell'unione europea in termini di energie fino al 2050, la situazione del sistema sanitario nazionale, l'inevitabile aumento dei cantieri e delle strutture per le energie rinnovabili, lo sbaglio nel considerare la prevenzione solo un obbligo di legge, il necessario cambiamento di questa visione della prevenzion