Hindsight and Sequential Rationality of Correlated Play

Driven by recent successes in two-player, zero-sum game solving and playing, artificial intelligence work on games has increasingly focused on algorithms that produce equilibrium-based strategies. However, this approach has been less effective at producing competent players in general-sum games or those with more than two players than in two-player, zero-sum games. An appealing alternative is to consider adaptive algorithms that ensure strong performance in hindsight relative to what could have been achieved with modified behavior. This approach also leads to a game-theoretic analysis, but in the correlated play that arises from joint learning dynamics rather than factored agent behavior at equilibrium. We develop and advocate for this hindsight rationality framing of learning in general sequential decision-making settings. To this end, we re-examine mediated equilibrium and deviation types in extensive-form games, thereby gaining a more complete understanding and resolving past misconceptions. We present a set of examples illustrating the distinct strengths and weaknesses of each type of equilibrium in the literature, and prove that no tractable concept subsumes all others. This line of inquiry culminates in the definition of the deviation and equilibrium classes that correspond to algorithms in the counterfactual regret minimization (CFR) family, relating them to all others in the literature. Examining CFR in greater detail further leads to a new recursive definition of rationality in correlated play that extends sequential rationality in a way that naturally applies to hindsight evaluation.Comment: Technical report for a paper in the proceedings of the thirty-fifth AAAI Conference on Artificial Intelligence (AAAI-21), February 2-9, 2021, Virtual. 26 pages and 15 figure

A Model for Solving the Optimal Water Allocation Problem in River Basins with Network Flow Programming When Introducing Non-Linearities

[EN] The allocation of water resources between different users is a traditional problem in many river basins. The objective is to obtain the optimal resource distribution and the associated circulating flows through the system. Network flow programming is a common technique for solving this problem. This optimisation procedure has been used many times for developing applications for concrete water systems, as well as for developing complete decision support systems. As long as many aspects of a river basin are not purely linear, the study of non-linearities will also be of great importance in water resources systems optimisation. This paper presents a generalised model for solving the optimal allocation of water resources in schemes where the objectives are minimising the demand deficits, complying with the required flows in the river and storing water in reservoirs. Evaporation from reservoirs and returns from demands are considered, and an iterative methodology is followed to solve these two non-network constraints. The model was applied to the Duero River basin (Spain). Three different network flow algorithms (Out-of-Kilter, RELAX-IVand NETFLO) were used to solve the allocation problem. Certain convergence issues were detected during the iterative process. There is a need to relate the data from the studied systems with the convergence criterion to be able to find the convergence criterion which yields the best results possible without requiring a long calculation time.We thank the Spanish Ministry of Economy and Competitivity (Comision Interministerial de Ciencia y Tecnologia, CICYT) for funding the projects INTEGRAME (contract CGL2009-11798) and SCARCE (program Consolider-Ingenio 2010, project CSD2009-00065). We also thank the European Commission (Directorate-General for Research & Innovation) for funding the project DROUGHT-R&SPI (program FP7-ENV-2011, project 282769). And last, but not least, to the Fundacion Instituto Euromediterraneo del Agua with the project "Estudio de Adaptaciones varias del modelo de optimizacion de gestiones de recursos hidricos Optiges".Haro Monteagudo, D.; Paredes Arquiola, J.; Solera Solera, A.; Andreu Álvarez, J. (2012). A Model for Solving the Optimal Water Allocation Problem in River Basins with Network Flow Programming When Introducing Non-Linearities. Water Resources Management. 26(14):4059-4071. https://doi.org/10.1007/s11269-012-0129-7S405940712614Ahuja R, Magnanti T, Orlin J (1993) Network flows: theory, algorithms and applications. Prentice Hall, New YorkAndreu J, Capilla J, Sanchís E (1996) AQUATOOL, a generalized decision-support system for water resources planning and operational management. J Hydrol 177:269–291Bersetkas D (1985) A unified framework for primal-dual methods in minimum cost network flows problems. Math Program 32:125–145Bersetkas D, Tseng P (1988) The relax codes for linear minimum cost network flow problems. Ann Oper Res 13:125–190Bersetkas D, Tseng P (1994) RELAX-IV: A faster version of the RELAX code for solving minimum cost flow problems. Completion Report under NSFGrant CCR-9103804. Dept. of Electrical Engineering and Computer Science, MIT, BostonChou F, Wu C, Lin C (2006) Simulating multi-reservoir operation rules by network flow model. ASCE Conf Proc 212:33Chung F, Archer M, DeVries J (1989) Network flow algorithm applied to California aqueduct simulation. J Water Resour Plan Manag 115:131–147Ford L, Fulkerson D (1962) Flows in networks. Princeton University Press, PrincetonFredericks J, Labadie J, Altenhofen J (1998) Decision support system for conjunctive stream-aquifer management. J Water Resour Plan Manag 124:69–78Harou JJ, Medellín-Azuara J, Zhu T et al (2010) Economic consequences of optimized water management for a prolonged, severe drought in California. Water Resour Res 46:W05522Hsu N, Cheng K (2002) Network Flow Optimization Model for Basin-Scale Water Supply Planning. J Water Resour Plan Manag 128:102–112Ilich N (1993) Improvement of the return flow allocation in the Water Resources Management Model of Alberta Environment. Can J Civ Eng 20:613–621Ilich N (2009) Limitations of network flow algorithms in river basin modeling. J Water Resour Plan Manag 135:48–55Kennington JL, Helgason RV (1980) Algorithms for network programming. John Wiley and Sons, New YorkKhaliquzzaman, Chander S (1997) Network flow programming model for multireservoir sizing. J Water Resour Plan Manag 123:15–21Kuczera G (1989) Fast Multireservoir Mulltiperiod Linear Programming Models. Water Resour Res 25:169–176Kuczera G (1993) Network linear programming codes for water-supply headworks modeling. J Water Resour Plan Manag 119:412–417Labadie J (2004) Optimal operation of multireservoir systems: state-of-the-art review. J Water Resour Plan Manag 130:93–111Labadie J (2006) MODSIM: river basin management decision support system. In: Singh W, Frevert D (eds) Watershed models. CRC, Boca Raton, pp 569–592Labadie J, Baldo M, Larson R (2000) MODSIM: decision support system for river basin management. Documentation and user manual. Dept. Of Civil Engineering, CSU, Fort CollinsManca A, Sechi G, Zuddas P (2010) Water supply network optimisation using equal flow algorithms. Water Resour Manag 24:3665–3678MMA (2000) Libro blanco del agua en España. Ministerio de Medio Ambiente, Secretaría general Técnica, Centro de PublicacionesMMA (2008) Confederación Hidrográfica del Duero. Memoria 2008. http://www.chduero.es/Inicio/Publicaciones/tabid/159/Default.aspx . Last accessed 25 June 2012Perera B, James B, Kularathna M (2005) computer software tool REALM for sustainable water allocation and management. J Environ Manag 77:291–300Rani D, Moreira M (2010) Simulation-optimization modeling: a survey and potential application in reservoir systems operation. Water Resour Manag 24:1107–1138Reca J, Roldán J, Alcaide M, López R, Camacho E (2001a) Optimisation model for water allocation in deficit irrigation systems I. Description of the model. Agric Water Manag 48:103–116Reca J, Roldán J, Alcaide M, López R, Camacho E (2001b) Optimisation model for water allocation in deficit irrigation systems II. Application to the Bembézar irrigation system. Agric Water Manag 48:117–132Sechi G, Zuddas P (2008) Multiperiod hypergraph models for water systems optimization. Water Resour Manag 22:307–320Sun H, Yeh W, Hsu N, Louie P (1995) Generalized network algorithm for water-supply-system optimization. J Water Resour Plan Manag 121:392–398Wurbs R (1993) Reservoir-system simulation and optimization models. J Water Resour Plan Manag 119:455–472Wurbs R (2005) Modeling river/reservoir system management, water allocation, and supply reliability. J Hydrol 300:100–113Yamout G, El-Fadel M (2005) An optimization approach for multi-sectoral water supply management in the greater Beirut area. Water Resour Manag 19:791–812Yates D, Sieber J, Purkey D, Hubert-Lee A (2005) WEAP21 – a demand-, priority-, and preference-driven water planning model. Part 1: model characteristics. Water Int 30:487–500Zoltay V, Vogel R, Kirshen P, Westphal K (2010) Integrated watershed management modeling: generic optimization model applied to the Ipswich river basin. J Water Resour Plan Manag 136:566–57

Valoración energética y diseño óptimo de impulsiones con caudal variable

[ES] En este trabajo se presenta una metodología para la valoración energética de estaciones de bombeo que abastecen caudales variables. El caudal impulsado se caracteriza como variable estocástica mediante su función de densidad. Dada la dificultad de conocer dicha función en la realidad cuando no existen aforadores, se deberá estimar mediante la adopción de hipótesis racionales. Las hipótesis de Clèment se han usado para caracterizar dicha función de densidad asociada al caudal distribuido en zonas regables a la demanda. Caracterizado el caudal, se determina el consumo energético a partir del conocimiento de las curvas características (altura-caudal y potencia-caudal) de cada uno de los impulsores. La metodología presentada permite la evaluación de cualquier sistema de bombeo teniendo en cuenta la variabilidad del caudal.López, R.; Reca Cardeña, J.; Camacho, E.; Roldán Cañas, J.; Alcaide García, M. (1995). Valoración energética y diseño óptimo de impulsiones con caudal variable. Ingeniería del Agua. 2(1):19-24. https://doi.org/10.4995/ia.1995.2653192421Clément, R. y Galand (1979) Irrigation par aspersion et réseaux collectifs de distribution sous pression. Editorial Eyrolles.Granados, A. (1990) Infraestructura de regadíos: redes colectivas de riego a presión (2a edición). E.T.S. de Ingenieros de Caminos, Canales y Puertos, Universidad Politécnica de Madrid.ITUR (1992) Catálogo comercial de bombas.López Luque, R. (1991) Optimización de sistemas de impulsión y distribución de agua para riego, Riegos y Drenajes XXI. 50:29-33.Mataix, C. (1975) Turbomáquinas hidráulicas. ICAI.Meyer, P.L. (1974) Introductory probability and statistical aplications. Addison-Wesley Publishing Company, Reading, Massachussets.Unidad Docente Mecánica de Fluidos (1992) Curso de ingeniería hidráulica aplicada a los sistemas de distribución de agua. Universidad Politécnica de Valencia

Aplicación de las técnicas de teledetección y SIG a la determinación y análisis de mapas de evapotranspiración

[ES] La estimación de la evapotranspiración es esencial en los sistemas de riego, en el cálculo de pérdidas de agua en embalses, en la estimación de balances hídricos, en las predicciones de escorrentía, así como en estudios climatológicos y meteorológicos. Las nuevas técnicas denominadas teledetección y sistemas de información geográfica (SIG) permiten el cálculo de la distribución espacial de este parámetro. Un nuevo modelo racional, SEBAL (Bastiaanssen, 1995), basado en la ecuación de conservación de la energía, ha sido aplicado en el estudio que se presenta. En este modelo se ha reducido el número de relaciones empíricas, además de presentar otras ventajas. El modelo ha sido calibrado y validado en una zona localizada en el Valle del Guadalquivir (España), a partir de una imagen del satélite Landsat-TM5 y de información climática. Posteriormente, el modelo ha sido utilizado con una resolución menor que la original por medio de un procedimiento de agregación de la imagen TM original. Este cambio en la resolución fue adoptado al objeto de comprobar la posible utilización de otras clases de imagen de satélite (por ejemplo, el NOAA). La evapotranspiración y otras variables obtenidas por teledetección se relacionan con ciertas características superficiales, por medio del uso de mapas de cultivos, suelos y mapas digitales de elevación del área de estudio.Se agradece a M. Menenti y W.G.M. Bastiaanssen del Department of Water Management in Arid Zones (DLO-Winand Staring Centre, Wageningen. The Netherlands) y sus colaboradores, todos los comentarios y material proporcionado para determinar la ET usando imágenes Landsat.Reca Cardeña, J.; Medina, JL.; Camacho, EF.; López, R.; Roldán Cañas, J. (1999). Aplicación de las técnicas de teledetección y SIG a la determinación y análisis de mapas de evapotranspiración. Ingeniería del Agua. 6(1):63-68. https://doi.org/10.4995/ia.1999.2778SWORD636861Bastiaanssen, W.G.M. y M. Menenti (1989). Surface reflectance and surface temperature in relation with soil type and regional energy fluxes. In: A.F. Bouwman (ed.). Soils and the greenhouse effect. John Wiley & Sons. Chichester, Reino Unido. 541 -549.Bastiaanssen, W.G.M. (1995). Regionalization of surface flux densities and moisture indicators in composite terrain. A remote sensing approach under clear skies in Mediterranean climates. Doctoral thesis, Wageningen Agricultural University, Wageningen. Holanda. 273 pp.Camacho, E. (1991). Estudio de recursos agrarios del término municipal de Aguilar de la Frontera. Sin publicar.ERDAS Imagine 8.2. User ManualESRI. (1990). Understanting GIS. The ARC/INFO Method. Esri. New York.ILWIS 1.4 User Manual (1993). The Integrated Land and Water Information System. ITC. Enschede, HolandaMedina, J.L; E. Camacho; R. López Luque. y J. Reca. (1996). Determinación de la ET con empleo de imágenes Landsat-TM5 y su agregación a resolución NOAA-AVHRR. (Aguadulce, Almería, 11-13 de junio de 1996).Medina Minuesa, J.L. (1996). Determinación y análisis de la evapotranspiración a nivel regional mediante teledetección y sistemas de información geográfica. Trabajo Profesional Fin de Carrera, ETSIAM, Córdoba.Medina J.L; E. Camacho; J. Reca; R. López y J. Roldán. (1998). Determination and analysis of regional evapotranspiration in Southern Spain based on remote sensing and GIS. Physics and Chemistry of the Earth, 23(4):427-432.Menenti, M., W.G.M. Bastiaanssen, D. van Eick y M.A. Abd El Karim (1989). Linear relationship between surface reflectance and temperature and their application to map evaporation of groundwater. in: Adv. Space Research. Volumen 9, No 1, 165-176.Price, J.C. (1980). The potential of remotely sensed thermal infrared data to infer surface soil moisture and evaporation. Water Resour. Res., 16, 787-795.Roerink, G. (1994). The impact of satellite sensor resolution on the regional evaporation statistics in large-scale irrigation schemes. A case study in the Mendoza Province, Argentine. Interne medeling 312. DLO Windand Staring Centre, Wageningen. Holanda.Reca, J.; J. Roldán; M. Alcaide y E. Camacho (1996). Perspectivas de la teledetección en zonas regables. Riegos y Drenajes XXI. 89:34-39

Random scenarios generation with minimun energy consumption model for sectoring optimization in pressurized irrigation networks using a simulated annealing approach

A pressurized irrigation network may operate in two ways, namely, on demand and organized under operating sectors. In the first case, the user decides when to irrigate, and the pumping station has to meet the discharge and pressure head requirements of the group of users that is demanding water at any time. In the second case, the operating hydrants at a given moment are previously established, which permits identification of scenarios related to lesser energy consumption. In this work, a new model was developed that identifies such scenarios. The optimization process is carried out by means of simulated annealing (SA). The model was applied to an example and the result obtained was compared with the same network operating on demand and sectorized using the criterion of hydrant elevation with respect to the pumping station. The scenario adopted for SA saved 11.8% and 15.5% in energy consumption compared with the two other scenarios, and decreased the installed power requirement by 38.3% and 21.6%, respectively.García Prats, A.; Guillem Picó, S.; Martínez Alzamora, F.; Jiménez Bello, MA. (2012). Random scenarios generation with minimun energy consumption model for sectoring optimization in pressurized irrigation networks using a simulated annealing approach. Journal of Irrigation and Drainage Engineering. 138(7):613-624. doi:10.1061/(ASCE)IR.1943-4774.0000452S613624138

Theorizing media production: the poverty of political economy

This article argues that the Political Economy of Communication (PEC) has generally failed to develop theories of media production. Such theory as exists has been heavily influenced by accounts of mass production and flexible specialization in Hollywood. Hollywood film production has been viewed as paradigmatic of media production in general, in the same way as Ford was for manufacturing, and these theories continue to influence accounts of production across media and cultural industries. The article tests the mass production/flexible specialization paradigm against both the evidence of the Hollywood case and Ford’s mass production system. An alternative paradigm, the theory of craft media production, is also examined. The article then attempts to show how applying organization theory and media economics can provide a more convincing explanation of media production and of the Hollywood case. Finally, the article briefly attempts to show how we might develop rich theoretical explanations of media production by exploring the relationships between economic, organizational and media-specific cultural elements

Bone Marrow Cells in Murine Colitis: Multi-Signal Analysis Confirms Pericryptal Myofibroblast Engraftment without Epithelial Involvement

This is an open-access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credite

The complement cascade as a mediator of tissue growth and regeneration

Recent evidence has demonstrated that the complement cascade is involved in a variety of physiologic and pathophysiologic processes in addition to its role as an immune effector. Research in a variety of organ systems has shown that complement proteins are direct participants in maintenance of cellular turnover, healing, proliferation and regeneration. As a physiologic housekeeper, complement proteins maintain tissue integrity in the absence of inflammation by disposing of cellular debris and waste, a process critical to the prevention of autoimmune disease. Developmentally, complement proteins influence pathways including hematopoietic stem cell engraftment, bone growth, and angiogenesis. They also provide a potent stimulus for cellular proliferation including regeneration of the limb and eye in animal models, and liver proliferation following injury. Here, we describe the complement cascade as a mediator of tissue growth and regeneration