A capacitated commodity trading model with market power

In this paper we consider the problem of a trader who purchases a commodity in one market and resells it in another. The trader is capacitated: the trading volume is limited by operational constraints, e.g., logistics. The two markets quote different prices, but the spread is reduced when trading takes place. We are interested in finding the optimal trading policy across the markets so as to obtain the maximum profit in the long-term, taking into account that the trading activity influences the price processes, i.e., market power. As in the no-market-power case, we find that the optimal policy is determined by three regions, where 1) move as much as possible from one market to the other; 2) the same in the opposite direction; or 3) do nothing. Finally, we use the model to analyze kerosene price differences between New York and Los Angeles.commodity trading; price processes; inventory management;

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Ex-Dividend Day Returns when Dividend and Capital Gains are Taxed at the Same Rate

Due to the overwhelming international evidence that stock prices drop by less than the dividend paid on ex-dividend days, the ex-dividend day anomaly is considered a stylized fact. Two main approaches have emerged to explain this empirical regularity: the tax-clientele hypothesis and the microstructure of financial markets. Although the most widely accepted explanation for this fact relies on taxes, the ex-dividend day anomaly has been reported even in countries where neither dividends nor capital gains are taxed. The 2006 tax reform in Spain established the same tax rate for dividends and capital gains. This paper investigates stock returns on ex-dividend days in the Spanish stock market after the 2006 tax reform using a random coefficient model. Contrary to previous research, we do not observe an ex-dividend day anomaly. Unlike previous investigations, which are mostly concerned with suggesting explanations as to why this anomaly has occurred, we are in the somewhat strange position of discussing why this anomaly has not occurred. Our findings are robust across companies and stock dividend yields, thus supporting a tax--based explanation for the ex-dividend day anomaly

An empirical analysis of the curvilinear relationship between slack and firm performance

This study performs an in-depth analysis of the curvilinear relationship between slack and future firm performance. Using a sample of US firms, we analyze the influence of three indicators of absorbed and unabsorbed slack on the two commonest dimensions of firm performance: profitability and sales growth. Although the relationship between most slack variables and firm performance is curvilinear, the inflection points (for both maximums and minimums) lie mainly outside the distribution range of the slack variables and, consequently, the curvilinear relationships between slack and performance are, in fact, neither U-shaped nor inverted U-shaped. Therefore, the influence of slack on performance can be positive or negative: linear for certain variables, but concave/convex for most variables analyzed in our study. An additional important finding is that the influence of slack on future profitability is usually the opposite of its influence on future sales growth: negative and positive, respectively, for absorbed slack; positive and negative, respectively, for financial slack. Results are robust to different lagged periods of the independent variables. The effects of equity and cash slacks on future performance are mainly negative, especially for longer time periods

Pitch production during the Roman period: an intensive mountain industry for a globalised economy?

The authors’ research project in the Pyrenees mountains has located and excavated Roman kilns for producing pitch from pine resin. Their investigations reveal a whole sustainable industry, integrated into the local environmental cycle, supplying pitch to the Roman network and charcoal as a spin-off to the local iron extractors. The paper makes a strong case for applying combined archaeological and palaeoenvironmental investigations in upland areas, showing mountain industries to have been not so much marginal and pastoral as key players in the economy of the Roman period and beyond it into the seventh century AD

Methodological insights into the study of centuriated field systems: a landscape archaeology perspective

The morphological identification of centuriated field systems has been characterised from its beginnings by methodological approaches mainly sustained on actus-based modular relationships and orientations. Many researchers dedicated to the identification of centuriations have only performed archaemorphological analyses based on interpretation of aerial photographs and maps without field verification or any other proof of the validity of their hypothsis. Their restitutions consisted of a set of lines over a map or an aerial photograph which often lacked precision and spatial resolution. This article argues that the study of centuriations should transform its aims, scope and methodologies to be converged with those presented by diachronic transdisciplinary landscape archaeology. In order to do so a series of integrated methodological approaches are exposed and their applicability discussed

Reputation and Trust in Sharing Economy Platforms: The Case of Traity

The concept of reputation is assiduously used in various fields such as communication, public relations, advertising, marketing and management. The convergence between the rise of new technologies linked to corporate communication has favoured the birth of what has been called online reputation. Thus, unprecedented behaviours have been generated that are establishing new social forms and even some authors speak of a new economy of reputation where society would be highly connected through networks and organizations that would operate in an ecosystem of permanent influence from the interest groups. With this premise, Traity arises the project that we analyzed in our research and that raises a reputational score that takes advantage of the fingerprint information to reproduce online trust as we understand it in the physical world, but without trying to reduce its people into a percentage, a number or some stars.Ciencias de la Comunicació

Análisis del puesto de gerente de instalaciones deportivas: tareas reactivas y proactivas

The need for organizations to adapt to increasingly complex environments has motivated research into standardized managerial tasks (reaction) and tasks related to anticipation, search and extra-role behaviour (proaction) (Toulson & Smith, 1994). This paper has two aims: a) to determine whether there are two distinguishable kinds of managerial tasks which can be identified as reactive/proactive; and b) to study the degree of development of reactive/proactive managerial tasks in recently professionalized sports installations. A survey based on task inventory techniques was specifically designed (Gael, 1988). The sample consisted of 73 managers of diferent kinds of sports installations. Results confirm the existence of reactive and proactive managerial performance. The results also show that proactive tasks are less developed than reactive ones. The implications of the study are discussed.La necesidad que tienen las organizaciones de afrontar ambientes cada vez más complejos, ha motivado la investigación no sólo de tareas directivas estandarizadas (reacción) sino también de aquellas relacionadas con la anticipación, búsqueda y comportamiento extra-rol (proacción) (Toulson y Smith, 1994). En este contexto, el presente trabajo tiene dos objetivos: a) observar si existen dos tipos diferenciados de tareas directivas que pudieran ser identificados como reacción/proacción; y b) explorar cuán desarrolladas están estas dos dimensiones en un ámbito, el de la gestión de instalaciones deportivas, de reciente profesionalización. Para su análisis, se ha desarrollado un cuestionario basado en las técnicas de inventarios de tareas (Gael, 1988). La muestra está formada por 73 gerentes de diferentes tipos de instalaciones deportivas. Los resultados confirman la enistencia de los dos tipos de dimensiones mencionados. Asimismo, se observa que las tareas proactivas están menos desarrolladas que las reactivas. Las implicaciones de estos resultados se detallan en la discusión del trabajo