Extracting Several Resource Deposits of Unknown Size: Optimal Order

Oil companies often announce revised estimates of their reserves. This indicates that stock uncertainty is a prevalent feature of natural resource industries. In this paper we consider the multi-deposit case where resource extraction produces information about the size of reserves. We show that the optimal order of extracting resource deposits depends both on the informational characteristics of the extraction process and on the extraction costs. Differences in extraction costs, a key consideration highlighted in Solow and Wan (1976), must be balanced against the relative value of information generated by the extraction of various deposits. Our model supplies an explanation of why high cost deposits are sometimes extracted when lower cost deposits have not been exhausted. Les compagnies pétrolières révisent souvent les chiffres de leurs réserves, ce qui indique que l’incertitude concernant les stocks est prévalente. Nous considérons le cas où l’extraction donne des informations sur la taille des réserves. Nous prouvons que l’ordre optimal d’exploitation des stocks dépend des propriétés du processus d’extraction concernant la révélation d’information et des coûts. La différence des coûts, qui est une considération importante dans Solow and Wan (1976), doit être balancée contre la valeur informative des réserves. Notre modèle fournit une explication du fait que les réserves plus coûteuses sont parfois exploitées avant l’épuisement des réserves moins coûteuses.order of extraction, value of information, uncertainty, ordre d’extraction, valeur de l’information, incertitude

ATD-2 Integrated Arrival/Departure/Surface (IADS) System Specification - Phase 2

The purpose of this document is to capture the core capabilities developed in ATD-2 Phase 2

A Differential Game Model of Tariff War

We present a simple two(-country) by two(-good) differental game model of international trade in which the governments of the two countries play a tariff-setting game. We explicitly derive a unilateral optimum tarifff rate and then a Markov-perfect equilibrium pair of tariff strategies (bilateral optimum tariff strategies) and compare the welfare level of each country among autarchic, free-trade, unilateral and bilateral optimum-tariff equilibria.Tariff-setting game, Durbale consumption good, Markov-perfect strategies, The rate of time preference

Faisceaux pervers, homomorphisme de changement de base et lemme fondamental de Jacquet et Ye

We give a geometric interpretation of the base change homomorphism between the Hecke algebra of GL(n) for an unramified extension of local fields of positive characteristic. For this, we use some results of Ginzburg, Mirkovic and Vilonen related to the geometric Satake isomorphism. We give new proof for these results in the positive characteristic case. By using that geometric interpretation of the base change homomorphism, we prove the fundamental lemma of Jacquet and Ye for arbitrary Hecke function in the the equal characteristic case.Comment: 66 pages, Latex, frenc

The effects of man-marking on work intensity in small-sided soccer games

The aim of this study was to examine the effect of manipulating defensive rules: with and without man-marking (MM and NMM) on exercise intensity in 3 vs. 3 small-sided games (SSGs). Twelve adolescent soccer players (age: 16.2 ± 0.7 years; body mass: 55.7 ± 6.4 kg; body height: 1.70 ± 0.07 m) participated in this repeated measures study. Each participant performed in four different SSGs formats: 3 vs. 3 MM with and without goals and 3 vs. 3 NMM with and without goals. Each SSG lasted 3 x 4 minutes interspersed with 4 minutes passive recovery. The percentage heart rate reserve (%HRreserve) was recorded continuously during SSG and session-rating of perceived exertion (session-RPE) after the SSG. MANOVA showed that defensive rule had significant effects on intensity (F = 5.37, p < 0.01). Specifically, MM during SSG induced significantly higher %HRreserve compared to NMM (Goal: 80.5 vs. 75.7%; No goal: 80.5 vs. 76.1%; p < 0.05, effect size = 0.91-1.06), irrespective of the presence or absence of goals. However, only MM with the presence of goals induced significant higher session-RPE compared to NMM (7.1 vs. 6.0; p < 0.05, effect size = 1.36), whereas no difference in session-RPE was observed between MM and NMM (7.4 vs. 6.9; p > 0.05, effect size = 0.63) when no goals were used. Higher intra-class reliability and lower coefficient of variation values were also reported in MM as compared to NMM. This study in youth soccer players shows there is ~4.5% increase in heart rate response by using the man-marking in 3 vs. 3 SSG thus the intensity of SSG can be significantly increased when using man-marking tactics

Development Aid in the Presence of Corruption: Differential Games among Donors

In this paper, we complement the work of Kemp and Shimomura (2002) by considering the case of many donors playing a dynamic non-cooperative game of foreign aid. We consider two models. Model 1 deals with the case where donor countries continually feel the warm glow of from the act of giving. Model 2 postulates that donors will stop giving aid when a target level of development is reached. One of the main results of Model 1 is that there are multiple equilibria that can be Pareto ranked. Another interesting result is that an increase in the level of corruption in the recipient country will reduce the aid level of the low aid equilibrium, but increase that of the high aid equilibrium. In Model 2, the equilibrium strategies are non-linear functions of the level of development. The flow of aid falls at a faster and faster rate as the target is approached. An increase in corruption will increase the flow of aid in this model. On présente deux modèles d’aide internationale dans lesquels deux pays avancés s’engagent dans un jeu dynamique. Dans le premier modèle, les aides apportent aux donateurs des gains moraux. On montre qu’une hausse de la corruption du pays sous-développé peut augmenter les aides. Il y a une multiplicité d’équilibres de Nash, qui peuvent être ordonnés sous le critère de Pareto. Dans le deuxième modèle, les pays donateurs cessent de donner aussitôt que le niveau du développement atteint un but fixé. On montre que l’équilibre de ce modèle implique que le flux d’aide devient de plus en plus faible au fur et à mesure que le niveau de développement s’approche du but fixé. Les pays avancés donnent plus si le taux de corruption augmente.development aid, corruption, dynamic games, differential games, aide internationale, corruption, jeux dynamiques, jeux différentiels