Hotelling Games on Networks: Efficiency of Equilibria

URL des Documents de travail : http://centredeconomiesorbonne.univ-paris1.fr/Documents de travail du Centre d'Economie de la Sorbonne 2014.33 - ISSN : 1955-611XWe consider a Hotelling game where a finite number of retailers choose a location, given that their potential customers are distributed on a network. Retailers do not compete on price but only on location, therefore each consumer shops at the closest store. We show that when the number of retailers is large enough, the game admits a pure Nash equilibrium and we construct it. We then compare the equilibrium cost bore by the consumers with the cost that could be achieved if the retailers followed the dictate of a benevolent planner. We perform this comparison in term of the induced price of anarchy, i.e., the ratio of the worst equilibrium cost and the optimal cost, and the induced price of stability, i.e., the ratio of the best equilibrium cost and the optimal cost. We show that, asymptotically in the number of retailers, these ratios are two and one, respectively.On considère un jeu à la Hotelling où un nombre fini de magasins doivent choisir un emplacement sachant que leurs clients potentiels sont situés sur un réseau donné. Les magasins ne sont pas en compétition sur les prix, mais seulement sur les emplacements. Nous montrons de manière constructive que lorsque le nombre de magasins est suffisamment grand ce jeu admet un équilibre de Nash en stratégies pures. Ensuite, nous comparons le coût de déplacement des consommateurs à l'équilibre avec le coût engendré par la situation optimale qui aurait été décidée par un planificateur extérieur. Pour cela, nous calculons le prix de l'anarchie induit, c'est-à-dire le ratio entre le pire coût à l'équilibre et le coût à l'optimum. Nous regardons aussi le prix de la stabilité induit, le ratio entre le meilleur coût à l'équilibre et le coût à l'optimum. Nous montrons que lorsque le nombre de vendeurs devient grand ces ratios tendent respectivement vers 2 et 1

BOUNDED COHOMOLOGY AND BINATE GROUPS

A group is boundedly acyclic if its bounded cohomology with trivial real coefficients vanishes in all positive degrees. Amenable groups are boundedly acyclic, while the first nonamenable examples are the group of compactly supported homeomorphisms of Rn (Matsumoto–Morita) and mitotic groups (Löh). We prove that binate (alias pseudo-mitotic) groups are boundedly acyclic, which provides a unifying approach to the aforementioned results. Moreover, we show that binate groups are universally boundedly acyclic. We obtain several new examples of boundedly acyclic groups as well as computations of the bounded cohomology of certain groups acting on the circle. In particular, we discuss how these results suggest that the bounded cohomology of the Thompson groups F, T, and V is as simple as possible

Twenty-year trends in the prevalence of modifiable cardiovascular risk factors in young acute coronary syndrome patients hospitalized in Switzerland

AIMS Modifiable cardiovascular risk factors (RFs) play a key role in the development of coronary artery disease. We evaluated 20-year trends in RF prevalence among young adults hospitalized with acute coronary syndromes (ACS) in Switzerland. METHODS AND RESULTS Data were analysed from the Acute Myocardial Infarction in Switzerland (AMIS) Plus registry from 2000 to 2019. Young patients were defined as those aged <50 years. Among 58 028 ACS admissions, 7073 (14.1%) were young (median 45.6 years, IQR 42.0-48.0), of which 91.6% had at least one modifiable RF and 59.0% had at least two RFs. Smoking was the most prevalent RF (71.4%), followed by dyslipidaemia (57.3%), hypertension (35.9%), obesity (21.7%), and diabetes (10.1%). Compared with older patients, young patients were more likely to be obese (21.7% vs. 17.4%, P < 0.001) and active smokers (71.4% vs. 33.9%, P < 0.001). Among young patients, between 2000 and 2019, there was a significant increase in the prevalence of hypertension from 29.0% to 51.3% and obesity from 21.2% to 27.1% (both Ptrend < 0.001) but a significant decrease in active smoking from 72.5% to 62.5% (Ptrend = 0.02). There were no significant changes in the prevalence of diabetes (Ptrend = 0.32) or dyslipidaemia (Ptrend = 0.067). CONCLUSION Young ACS patients in Switzerland exhibit a high prevalence of RFs and are more likely than older patients to be obese and smokers. Between 2000 and 2019, RF prevalence either increased or remained stable, except for smoking which decreased but still affected approximately two-thirds of young patients in 2019. Public health initiatives targeting RFs in young adults in Switzerland are warranted

Formation of the Xigaze Metamorphic Sole under Tibetan continental lithosphere reveals generic characteristics of subduction initiation

Metamorphic soles found under allochthonous oceanic lithosphere, or ophiolites, are interpreted as derived from lower plate oceanic crust material accreted to upper plate mantle during intraoceanic subduction initiation. Their metamorphic evolution is inferred to reflect the thermal structure at the site of subduction nucleation, with granulite-bearing soles linked to initiation at hot spreading centers. Here we present garnet Lu-Hf geochronology for the granulite-bearing sole of the Xigaze ophiolite in South Tibet, whose oceanic crust formed ∼130 Ma through continental forearc extension. Our study shows that sole metamorphism was ongoing by 144 Ma, implying that north-directed subduction began at least 14 million years before oceanic forearc spreading. The upper plate at the time of subduction initiation was thus continental, not oceanic. Our results demonstrate that metamorphic characteristics of soles are independent of the specific tectonic setting at the subduction nucleation site and rather provide generic constraints on the subduction initiation process

Formation of the Xigaze Metamorphic Sole under Tibetan continental lithosphere reveals generic characteristics of subduction initiation

Metamorphic soles found under allochthonous oceanic lithosphere, or ophiolites, are interpreted as derived from lower plate oceanic crust material accreted to upper plate mantle during intraoceanic subduction initiation. Their metamorphic evolution is inferred to reflect the thermal structure at the site of subduction nucleation, with granulite-bearing soles linked to initiation at hot spreading centers. Here we present garnet Lu-Hf geochronology for the granulite-bearing sole of the Xigaze ophiolite in South Tibet, whose oceanic crust formed ∼130 Ma through continental forearc extension. Our study shows that sole metamorphism was ongoing by 144 Ma, implying that north-directed subduction began at least 14 million years before oceanic forearc spreading. The upper plate at the time of subduction initiation was thus continental, not oceanic. Our results demonstrate that metamorphic characteristics of soles are independent of the specific tectonic setting at the subduction nucleation site and rather provide generic constraints on the subduction initiation process

Determinación de intervalos básicos de salud en tortugas resbaladoras (Trachemys scripta emolli) del Refugio de Vida Silvestre Caño Negro, Costa Rica

The objective of this study was to determinate blood parameters and the presence of parasites in a wild population of tortugas deslizantes (Trachemys scripta emolli) during the dry season of 2013 in the Caño Negro Wildlife Refuge in Costa Rica. Individuals were captured from different gaps using nets. Blood samples were taken to determine chemical parameters of blood and hematocrit, as well as morphological values and body conditions. In addition, samples of feces and ectoparasites were collected. The hematocrit CI 95.0% was [14.7091, 18.7356] and no significant difference were found between sexes. The 95% CI for blood chemistry parameters were: AST (U/L) [87.6214, 148.929], CK (U/L) [1439.2, 2487.08], AU (umol/L) [68.22, 90.43 ], GLU (mmol/L) [4.26, 5.47], PHOS [0.46, 0.61], Ca (mmol/L) [1.99, 2.15], PT (g/L) [22.16, 24.44], K (mmol/L ) [3.31, 3.83], and Na (mmol/L) [127.92, 130.93]. A total of 21 fecal samples was obtained, of which 10 were positive for parasites (23.8% Strongyloides, 14.3% Ascaridia, 9.5% Coccidia, and 9.5% Pentastomid). A leech from the Rhynchobdellidae family was the only ectoparasite found (Placobdella sp.). None of the individuals were ill or had abscesses in relation to their morphological attributes.&nbsp; Based on the results, the handling used does not represent a risk for this reptile population.El objetivo de este trabajo es determinar los parámetros sanguíneos y la presencia de parásitos en una población salvaje de tortugas deslizantes (Trachemys scripta emolli), durante la estación seca de 2013, en el Refugio de Vida Silvestre Caño Negro, Costa Rica. Utilizando redes, los individuos fueron capturados de diferentes huecos. Se tomó muestras de sangre para determinar los parámetros químicos de esta y el hematocrito, así como los valores morfológicos y las condiciones corporales. Además, se recolectaron muestras de heces y ectoparásitos. El IC del hematocrito 95.0 % fue [14 7091, 18 7356] y no se encontraron diferencias significativas entre los sexos. Los IC del 95 % para los parámetros de la química sanguínea fueron: AST (U/L) [87 6214, 148 929], CK (U/L) [1439.2, 2487.08], AU (umol/L) [68.22, 90.43], GLU (mmol/L) [4.26, 5.47], PHOS [0.46, 0.61], Ca (mmol/L) [1.99, 2.15], PT (g/L) [22.16, 24.44], K (mmol/L) [3.31, 3.83 ] y Na (mmol/L) [127.92, 130.93]. También se obtuvo 21 muestras de heces, de las cuales 10 fueron positivas para parásitos (23.8 % Strongyloides, 14.3 % &nbsp;Ascaridia, 9.5 % Coccidia y 9.5 % Pentastomida). Una sanguijuela de la familia Rhynchobdellidae fue el único ectoparásito encontrado (Placobdella sp.). Ninguno de los individuos estaba enfermo o presentaba abscesos en relación con sus atributos morfológicos. Según los resultados, el manejo empleado no representa un riesgo para esta población de reptiles

The Boost 4.0 Experience

In the last few years, the potential impact of big data on the manufacturing industry has received enormous attention. This chapter details two large-scale trials that have been implemented in the context of the lighthouse project Boost 4.0. The chapter introduces the Boost 4.0 Reference Model, which adapts the more generic BDVA big data reference architectures to the needs of Industry 4.0. The Boost 4.0 reference model includes a reference architecture for the design and implementation of advanced big data pipelines and the digital factory service development reference architecture. The engineering and management of business network track and trace processes in high-end textile supply are explored with a focus on the assurance of Preferential Certification of Origin (PCO). Finally, the main findings from these two large-scale piloting activities in the area of service engineering are discussed.publishersversionpublishe

AI-augmented business process management systems: a research manifesto

AI-augmented Business Process Management Systems (ABPMSs) are an emerging class of process-aware information systems, empowered by trustworthy AI technology. An ABPMS enhances the execution of business processes with the aim of making these processes more adaptable, proactive, explainable, and context-sensitive. This manifesto presents a vision for ABPMSs and discusses research challenges that need to be surmounted to realize this vision. To this end, we define the concept of ABPMS, we outline the lifecycle of processes within an ABPMS, we discuss core characteristics of an ABPMS, and we derive a set of challenges to realize systems with these characteristics

Augmented Business Process Management Systems: A Research Manifesto

Augmented Business Process Management Systems (ABPMSs) are an emerging class of process-aware information systems that draws upon trustworthy AI technology. An ABPMS enhances the execution of business processes with the aim of making these processes more adaptable, proactive, explainable, and context-sensitive. This manifesto presents a vision for ABPMSs and discusses research challenges that need to be surmounted to realize this vision. To this end, we define the concept of ABPMS, we outline the lifecycle of processes within an ABPMS, we discuss core characteristics of an ABPMS, and we derive a set of challenges to realize systems with these characteristics.Comment: 19 pages, 1 figur