Strategic Information Acquisition in Networked Groups with "Informational Spillovers"

This paper develops a model of costly information acquisition by agents who are connected through a network. For a exogenously given network, each agent decides first on information acquisition from his neighbors and then, after processing the information acquired, takes an action. Each agent is concerned about the extent to which other agents align their actions with the underlying state. A new equilibrium notion, which is in the spirit of perfect Bayesian equilibrium, is proposed to analyze information acquisition decisions within networked groups. This equilibrium notion allows each agent to compute, when deciding about information acquisition, the extent to which changes in his information acquisition decision will affect his own perception of future expected payos. Agents anticipate and incorporate such changes in their information acquisition decisions. Both the efficient and the equilibrium information acquisition proles are characterized and the compatibility between them is related to the density of the network.Incomplete Information, Information Acquisition, Communication Networks, Informational Spillovers, Coordination

Notes on the Suboptimality Result by J. D. Geanakoplos and H. M. Polemarchakis (1986)

J. D. Geanakoplos and H. M. Polemarchakis (1986) prove the generic constrained suboptimality of equilibrium allocations in two period economies with incomplete markets. They perturb asset prices at equilibrium when the degree of market incompleteness equals one. However, since prices are not fundamentals that parameterize the economy, a generic result cannot be obtained in such a way. In these notes we provide complete and detailed version of their proof in which the arguments do not depend on the dimension of the market incompleteness and in which utilities and endowments are perturbed.Incomplete Asset Markets, Constrained Suboptimality, Transversality Theory

Yield Management As A Pricing Mechanism

Consumers nowadays frequently make their purchases online. One common pricing strategy on the Internet is demand-based pricing, which allows firms to adapt prices to the demand for their products. This mechanism can undoubtedly be employed more efficiently on the Internet, due to how quickly demand information can be obtained. Within demand-based pricing, one very well-known practice is yield management. This practice was pioneered by airlines, but has spread in recent years to industries such as hotels, rental cars and cruise lines to name but a few industries. The application of yield management was an authentic revolution for the traditional concept of pricing, but has shown that it can be a good strategy when used correctly. Applying yield management requires firms to understand consumer purchasing behavior in order to compare present demand with the demand that is anticipated in the future. Yield management techniques imply the allocation of a fixed capacity to different prices and segments of consumers in order to maximize income. Yield management is sometimes confused with a well-known segmentation strategy called time-based pricing. For this reason, in this paper we highlight the main demand-based pricing strategies that are now being used on the Internet, placing special emphasis on yield management

Biomechanics of <i>Machaeracanthus</i> pectoral fin spines provide evidence for distinctive spine function and lifestyle among early chondrichthyans

Acanthodians are a major group of Paleaozoic jawed vertebrates that constitute a paraphyletic assemblage of stem-chondrichthyans (Brazeau and Friedman, 2015). Representatives of this group are characterized, among other traits, by the presence of bony spines in front of all paired and median fins except the caudal (Denison, 1979), which has given rise to their colloquial name of 'spiny sharks'. The occurrence of pectoral fin spines is recognized as a potential gnathostome synapomorphy (Miller et al., 2003) or symplesiomorphy (Coates, 2003), being also present in other major groups of Paleaozoic jawed vertebrates, including placoderms (Young, 2010), 'non-acanthodian' chondrichthyans (Miller et al., 2003), and osteichthyans (Zhu et al., 1999). However, this trait was independently lost in the later evolutionary history of these lineages and is absent in most living representatives (Coates, 2003; Miller et al., 2003), with the exception of catfishes (Siluriformes), that acquired pectoral fin spines as an evolutionary reversion (Price et al., 2015). As a consequence, the paucity of living analogsue precludes deriving functional interpretations of those structures and the role that they fulfilled in life remains unclear, despite this having the potential to enrich our understanding on the ecologies and lifestyles of groups of early jawed vertebrates. Machaeracanthus constitutes a genus of acanthodians that ranged from the Late Silurian to the Middle Devonian, which is known from fin spines, scales, and a few endoskeletal remains (Burrow et al., 2010; Botella et al., 2012). The spines of this genus differ from the fin spines of all other acanthodians and sharks in presenting a marked cross-sectional asymmetry and a totally enclosed central canal, which is usually open along the proximal end of the trailing edge in other taxa (Burrow et al., 2010). The description of wear patterns at the tips of pectoral fin spines of Machaeracanthus and their peculiar arrangement in pairs has led some authors to propose that these elements could have been used as 'snow-shoes' to lay on and prevent sinking into the substrate below or even to propel itself along the bottom (Südkamp and Burrow, 2007). Here, we test this hypothesis through beam theory analyses and provide evidence that the biomechanical properties of Machaeracanthus pectoral fin spines are compatible with this interpretation, thus shedding light on the diversity of the functions of these intriguing anatomical structures and the lifestyles of some of the earliest jawed vertebrates

Gas-phase formation of glycolonitrile in the interstellar medium

Our automated reaction discovery program, AutoMeKin, has been utilized to investigate the formation of glycolonitrile (HOCH$_{2}$CN) in the gas phase under the low temperatures of the interstellar medium (ISM). The feasibility of a proposed pathway depends on the absence of barriers above the energy of reactants and the availability of the suggested precursors in the ISM. Based on these criteria, several radical-radical reactions and a radical-molecule reaction have been identified as viable formation routes in the ISM. Among the radical-radical reactions, OH+CH$_{2}$CN appears to be the most relevant, considering the energy of the radicals and its ability to produce glycolonitrile in a single step. However, our analysis reveals that this reaction produces hydrogen isocyanide (HNC) and formaldehyde (CH$_{2}$O), with rate coefficients ranging from (7.3-11.5)$\times$10$^{-10}$ cm$^3$ molecule$^{-1}$ s$^{-1}$ across the temperature range of 10-150 K. This finding is particularly interesing given the persistently unexplained overabundance of hydrogen isocyanide in the ISM. Among the radical-molecule reactions investigated, the most promising one is OH+CH$_{2}$CNH, which forms glycolonitrile and atomic hydrogen with rate coefficients in the range (0.3-6.6)$\times$10$^{-10}$ cm$^3$ molecule$^{-1}$ s$^{-1}$ within the 10-150 K temperature range. Our calculations indicate that the formation of both hydrogen isocyanide and glycolonitrile is efficient under the harsh conditions of the ISM

Analysis Of Hotel Internet Booking Users

The number of tourist products sold on the Internet has increased remarkably in recent years. The hotel industry has figured prominently in this boom due to hotel bookings made via the Internet becoming increasingly popular. The reason for this upturn in online bookings is, in many cases, the possibility of booking at any time and the possible existence of lower prices. In order to achieve these lower prices, consumers must accept certain restrictions or conditions that hotels use to manage demand through yield management strategies.This paper analyses hotel Internet booking users in order to ascertain their socio-demographic characteristics and behaviour in regard to online purchase decisions. The ultimate goal is therefore to determine a user profile. With this information, hotel managers will be able to manage Internet hotel bookings

Gene expression changes in mononuclear cells from patients with metabolic syndrome after acute intake of phenol-rich virgin olive oil

RIGHTS : This article is licensed under the BioMed Central licence at http://www.biomedcentral.com/about/license which is similar to the 'Creative Commons Attribution Licence'. In brief you may : copy, distribute, and display the work; make derivative works; or make commercial use of the work - under the following conditions: the original author must be given credit; for any reuse or distribution, it must be made clear to others what the license terms of this work are.Abstract Background Previous studies have shown that acute intake of high-phenol virgin olive oil reduces pro-inflammatory, pro-oxidant and pro-thrombotic markers compared with low phenols virgin olive oil, but it still remains unclear whether effects attributed to its phenolic fraction are exerted at transcriptional level in vivo. To achieve this goal, we aimed at identifying expression changes in genes which could be mediated by virgin olive oil phenol compounds in the human. Results Postprandial gene expression microarray analysis was performed on peripheral blood mononuclear cells during postprandial period. Two virgin olive oil-based breakfasts with high (398 ppm) and low (70 ppm) content of phenolic compounds were administered to 20 patients suffering from metabolic syndrome following a double-blinded, randomized, crossover design. To eliminate the potential effect that might exist in their usual dietary habits, all subjects followed a similar low-fat, carbohydrate rich diet during the study period. Microarray analysis identified 98 differentially expressed genes (79 underexpressed and 19 overexpressed) when comparing the intake of phenol-rich olive oil with low-phenol olive oil. Many of these genes seem linked to obesity, dyslipemia and type 2 diabetes mellitus. Among these, several genes seem involved in inflammatory processes mediated by transcription factor NF-&#954;B, activator protein-1 transcription factor complex AP-1, cytokines, mitogen-activated protein kinases MAPKs or arachidonic acid pathways. Conclusion This study shows that intake of virgin olive oil based breakfast, which is rich in phenol compounds is able to repress in vivo expression of several pro-inflammatory genes, thereby switching activity of peripheral blood mononuclear cells to a less deleterious inflammatory profile. These results provide at least a partial molecular basis for reduced risk of cardiovascular disease observed in Mediterranean countries, where virgin olive oil represents a main source of dietary fat. Admittedly, other lifestyle factors are also likely to contribute to lowered risk of cardiovascular disease in this region.Published versio

Improcedencia de la determinación estimativa de las cuotas de seguridad social en sector de la construcción

Esta investigación es importante desarrollarla porque servirá de base, para analizar la problemática en la improcedencia en la estimación de las cuotas obrero-patronales en Las empresas dedicadas a la construcción, demostrando la ilegalidad en el actuar de la autoridad y otorgar a los contribuyentes que se encuentran específicamente en la esta industria certeza jurídica.  Dentro de la problemática podemos darnos cuenta de que se trasgrede el principio de legalidad tributaria al aplicar el “Artículo 18 del Reglamento el Seguro Social obligatorio para los trabajadores de la construcción por obra o tiempo determinado”, a los contribuyentes dedicados a la construcción, de manera supletoria aun y cuando los contribuyentes cumplen con lo que la Propia Ley del Seguro Social le señala. La opción de aplicar el artículo 18 del Reglamento se presenta solamente cuando el contribuyente ha incumplido con las obligaciones que dispone la propia ley, hecho que en la actualidad se aplica de manera discrecional por la autoridad, ocasionando que le determinen diferencias en los montos que pago realmente por la mano de obra. Si los patrones cumplen con todos los requisitos que la ley del Seguro social para la determinación de las Cuotas obrero-Patronales, la Autoridad no se encontraría facultada para aplicar la Estimativa del Artículo 18 del Reglamento. Cuando los contribuyentes cumplan con el soporte documental y legal que la ley le exige, estarán en el derecho de solicitar los medios de defensa que tienen a su disposición

Fisher score-based feature selection for ordinal classification: a social survey on subjective well-being

This paper approaches the problem of feature selection in the context of ordinal classification problems. To do so, an ordinal version of the Fisher score is proposed. We test this new strategy considering data from an European social survey concerning subjective well-being, in order to understand and identify the most important variables for a person’s happiness, which is represented using ordered categories. The input variables have been chosen according to previous research, and these have been categorised in the following groups: demographics, daily activities, social well-being, health and habits, community well-being and personality/opinion. The proposed strategy shows promising results and performs significantly better than its nominal counterpart, therefore validating the need of developing specific ordinal feature selection methods. Furthermore, the results of this paper can shed some light on the human psyche by analysing the most and less frequently selected variables