Overconfidence and market efficiency with heterogeneous agents

We study financial markets in which both rational and overconfident agents coexist and make endogenous information acquisition decisions. We demonstrate the following irrelevance result: when a positive fraction of rational agents (endogeneously) decides to become informed in equilibrium, prices are set as if all investors were rational, and as a consequence the overconfidence bias does not aect informational efficiency, price volatility, rational traders’ expected profits or their welfare. Intuitively, as overconfidence goes up, so does price infornativeness, which makes rational agents cut their information acquisition activities, effectively undoing the standard effect of more aggressive trading by the overconfident.Partially revealing equilibria, overconfidence, rational expectations, information

Overconfidence and Market Efficiency with Heterogeneous Agents

We study financial markets in which both rational and overconfident agents coexist and make endogenous information acquisition decisions. We demonstrate the following irrele- vance result: when a positive fraction of rational agents (endogenously) decides to become informed in equilibrium, prices are set as if all investors were rational, and as a conse- quence the overconfidence bias does not affect informational efficiency, price volatility, ra- tional traders expected profits or their welfare. Intuitively, as overconfidence goes up, so does price informativeness, which makes rational agents cut their information acquisition activities, effectively undoing the standard effect of more aggressive trading by the overcon- fident. The main intuition of the paper, if not the irrelevance result, is shown to be robust to different model specifications.partially revealing equilibria, overconfidence, rational expectations, information acquisition, price informativeness.

Uncertainty, Information Acquisition, and Price Swings in Asset Markets

This article analyses costly information acquisition in asset markets with Knightian uncertainty about the asset fundamentals. In these markets, acquiring information not only reduces the expected variability of the fundamentals for a given distribution (i.e. risk). It also mitigates the uncertainty about the true distribution of the fundamentals. Agents who lack knowledge of this distribution cannot correctly interpret the information other investors impound into the price. We show that, due to uncertainty aversion, the incentives to reduce uncertainty by acquiring information increase as more investors acquire information. When uncertainty is high enough, information acquisition decisions become strategic complements and lead to multiple equilibria. Swift changes in information demand can drive large price swings even after small changes in Knightian uncertaint

Investigation on performances of asphalt mixtures made with Reclaimed Asphalt Pavement: Effects of interaction between virgin and RAP bitumen

According to most recent surveys, the European area produced 265 mil tonnes of asphalt for road applications in 2014. In the same year, the amount of available RAP was more than 50 mil tonnes. The use of RAP in new blended mixes reduces the need of neat bitumen, making RAP recycling economically attractive. Despite the economic and environmental benefits, road authorities tend to limit the use of RAP in asphalt mixes due to uncertainty about field performances. The present study focuses on the interaction between neat and RAP bitumen in asphalt mixes made with different RAP content. The effects of RAP on physical and rheological properties of the final bituminous blend were investigated. This study is part of a wider research, where a specific type of asphalt mixture was produced with different RAP contents being 10%, 20% and 30% by mass of the mix. Bitumen was extracted and recovered from asphalt mixes, then it was subjected to the following laboratory tests: standard characterization, dynamic viscosity and rheological analysis with DSR. Findings showed that the effects of RAP bitumen on the final blend varied in proportion to RAP content. A threshold value of RAP content was found, below which bitumen was not subjected to significant changes in physical and rheological properties. Practical implications on production methods and paving of RAP mixes are also proposed. Keywords: Reclaimed Asphalt Pavement (RAP), Recycling, Bitumen blending, Bitumen rheolog

Application of Mining Waste Powder as filler in Hot Mix Asphalt

Asphalt concrete mixtures are composed of two main components: aggregates and binder. The fraction of aggregates passing through the 63\u3bcm sieve is traditionally considered as filler. During years, several researches have shown the importance and the influence of filler in controlling the physical and mechanical properties of Hot Mix Asphalts (HMAs). The main objective of this research is to investigate and to assess the effects given by the use of Mining Waste Powder (MWP) within HMAs in total substitution of traditional limestone filler. The MWP used in this study is a residual of the tungsten extraction process in Panasqueira (Portugal) mine. The evaluation of properties conferred by the presence of the MWP filler within asphalt mixtures is based on a physical and mechanical laboratory characterization. For this purpose, tests have been performed both on bituminous mastics and on HMAs. Results indicate that the use of MWP in total substitution of limestone filler does not negatively affect the performances of HMAs and their bituminous mastics

Rheological characterization of bituminous mastics containing waste bleaching clays

Bleaching clays are mostly used in food industries to clarify vegetal oils. After use they are generally dumped as waste (stage 1) or used in green innovative plants to feed biogas reactors (stage 2). In latter stage the initial residual oil content (ap-prox. 25% by mass) is reduced to less than 1% by the biological process. In this study the bleaching clays effects on bituminous mastics of a traditional binder course Hot Mix Asphalt have been investigated. The physical characteristics of the two bleaching clays and of a traditional limestone filler were also studied. DSR rheological tests at high and low temperatures were performed on mastics samples containing different amounts of fillers (limestone, stage 1 or stage 2). The addition of the different waste bleaching clays significantly affects the rheological behav-ior of the mastics: the filler from stage 2 increases the mastic stiffness improving the resistance to permanent deformations as shown by repeated creep tests, while the filler from stage 1 strongly interacts with the bitumen reducing the mechanical characteristics of the mastics at all temperatures

Multi-Scale Rheo-Mechanical Study of SMA Mixtures Containing Fine Crumb Rubber in a New Dry-Hybrid Technology

Aiming to study the rheo-mechanical effects of fine crumb rubber into gap graded stone mastic asphalt (SMA) mixtures, a multi-scale experimental approach was adopted. Therefore, in the perspective of the reuse of end of life tires’ in asphalt layers, the adopted new dry-hybrid technology effects have been investigated from the mastic, mortar and mixture points of view. The new rubberized asphalt production technology allows the use of rubber powder as filler, the rubber amount optimization being validated through multi-scale performance tests. Mastics and mortars’ complex modulus measured with dynamic shear and torsional tests were related to the mixture stiffness modulus recorded in direct tension-compression mode. The rheological properties of mastic are strictly influenced by the rubber presence, and consequently the asphalt mixtures stiffness and thermo-sensitivity are connected to the mastic and mortar rheo-mechanical behavior. Results are consistent through the adopted approach and reveal that with the new dry-hybrid technology, overcoming the wet and dry limits, it seems to be possible obtaining more durable and eco-friendly bituminous pavement layers

Application of Mining Waste Powder as filler in Hot Mix Asphalt

Asphalt concrete mixtures are composed of two main components: aggregates and binder. The fraction of aggregates passing through the 63μm sieve is traditionally considered as filler. During years, several researches have shown the importance and the influence of filler in controlling the physical and mechanical properties of Hot Mix Asphalts (HMAs). The main objective of this research is to investigate and to assess the effects given by the use of Mining Waste Powder (MWP) within HMAs in total substitution of traditional limestone filler. The MWP used in this study is a residual of the tungsten extraction process in Panasqueira (Portugal) mine. The evaluation of properties conferred by the presence of the MWP filler within asphalt mixtures is based on a physical and mechanical laboratory characterization. For this purpose, tests have been performed both on bituminous mastics and on HMAs. Results indicate that the use of MWP in total substitution of limestone filler does not negatively affect the performances of HMAs and their bituminous mastics

An agent-based system for maritime search and rescue operations.

Maritime search and rescue operations are critical missions involving personnel, boats, helicopter, aircrafts in a struggle against time often worsened by adversary sea and weather conditions. In such a context, telecommunication and in- formation systems may play a crucial role sometimes concurring to successfully accomplish the mission. In this paper we present an application able to localize the vessel who has launched a rescue request and to plan the most effective path for rescue assets. The application has been realised as a distributed and open multi-agent system deployed on rescue vehicles as well as on a land maritime stations of the Italian Coast Guard. The system is going to be tested in real scenarios by the Coast Guard

Patient-reported outcome measures after periodontal surgery

ObjectivesThe present study aimed to explore the impact of different periodontal surgical treatments on the quality of life and postoperative morbidity.Materials and methodsThe present study is a single-center, prospective, observational cohort trial. One hundred fifty-five patients, referred to the Periodontal Department of Bologna University who needed periodontal surgical treatment, were recruited. The self-reported perception of the postoperative course was assessed using the following anonymous questionnaires: Italian oral health impact profile (I-OHIP-14), visual analog scale (VAS) to evaluate the intensity of the pain, and 5-point Likert scale.ResultsPatients reported a mean OHIP-14 total score of 9.87 +/- 8.5 (range 0-42), significantly influenced by the female sex, flap extension, and periodontal dressing. A mean VAS score of 2.96 +/- 2.39 (range 0-9) was calculated, and was found to be influenced by the presence of vertical releasing incisions and palatal flap extension. Of the 155 subjects, 40 (25.8%) patients reported bleeding as a post-surgical complication, 96 (61.9%) swelling, 105 (67.7%) eating discomfort, and 44 (28.4%) reported speech discomfort.ConclusionsWithin the limitations of the nature of the present study, periodontal surgical procedures have a low impact on patients' quality of life evaluated through the OHIP-14 and VAS pain questionnaires.Clinical relevancePeriodontal surgical procedures are safe procedures, with a limited duration of postoperative discomfort as well as the incidence of complications