Diffusion of shared goods in consumer coalitions. An agent-based model

This paper focuses on the process of coalition formation conditioning the common decision to adopt a shared good, which cannot be afforded by an average single consumer and whose use cannot be exhausted by any single consumer. An agent based model is developed to study the interplay between these two processes: coalition formation and diffusion of shared goods. Coalition formation is modelled in an evolutionary game theoretic setting, while adoption uses elements from both the Bass and the threshold models. Coalitions formation sets the conditions for adoption, while diffusion influences the consequent formation of coalitions. Results show that both coalitions and diffusion are subject to network effects and have an impact on the information flow though the population of consumers. Large coalitions are preferred over small ones since individual cost is lower, although it increases if higher quantities are purchased collectively. The paper concludes by connecting the model conceptualisation to the on-going discussion of diffusion of sustainable goods, discussing related policy implications

Models for the modern power grid

This article reviews different kinds of models for the electric power grid that can be used to understand the modern power system, the smart grid. From the physical network to abstract energy markets, we identify in the literature different aspects that co-determine the spatio-temporal multilayer dynamics of power system. We start our review by showing how the generation, transmission and distribution characteristics of the traditional power grids are already subject to complex behaviour appearing as a result of the the interplay between dynamics of the nodes and topology, namely synchronisation and cascade effects. When dealing with smart grids, the system complexity increases even more: on top of the physical network of power lines and controllable sources of electricity, the modernisation brings information networks, renewable intermittent generation, market liberalisation, prosumers, among other aspects. In this case, we forecast a dynamical co-evolution of the smart grid and other kind of networked systems that cannot be understood isolated. This review compiles recent results that model electric power grids as complex systems, going beyond pure technological aspects. From this perspective, we then indicate possible ways to incorporate the diverse co-evolving systems into the smart grid model using, for example, network theory and multi-agent simulation.Comment: Submitted to EPJ-ST Power Grids, May 201

Stochastic network formation and homophily

This is a chapter of the forthcoming Oxford Handbook on the Economics of Networks

Spatial interactions in agent-based modeling

Agent Based Modeling (ABM) has become a widespread approach to model complex interactions. In this chapter after briefly summarizing some features of ABM the different approaches in modeling spatial interactions are discussed. It is stressed that agents can interact either indirectly through a shared environment and/or directly with each other. In such an approach, higher-order variables such as commodity prices, population dynamics or even institutions, are not exogenously specified but instead are seen as the results of interactions. It is highlighted in the chapter that the understanding of patterns emerging from such spatial interaction between agents is a key problem as much as their description through analytical or simulation means. The chapter reviews different approaches for modeling agents' behavior, taking into account either explicit spatial (lattice based) structures or networks. Some emphasis is placed on recent ABM as applied to the description of the dynamics of the geographical distribution of economic activities, - out of equilibrium. The Eurace@Unibi Model, an agent-based macroeconomic model with spatial structure, is used to illustrate the potential of such an approach for spatial policy analysis.Comment: 26 pages, 5 figures, 105 references; a chapter prepared for the book "Complexity and Geographical Economics - Topics and Tools", P. Commendatore, S.S. Kayam and I. Kubin, Eds. (Springer, in press, 2014

Temporary Clusters and Knowledge Creation: The Case of Tourism@

With respect to the knowledge-based-view and management science, innovations contribute to a company's competitiveness. And for successful innovation process, companies need to share, create and combine their internal knowledge as well as managing their external relationships and opportunities. Consequently, it is widely accepted that clusters - systemic and local configurations - by supporting horizontal and vertical knowledge exchange could be a fundamental mean for innovation. However, the prolific literature on clusters analyse them only as durable and permanent entities. Yet, interestingly, some forms of temporary organizations as trade fairs, conventions and other professional gatherings, are similar to permanent clusters, but in a temporary, repeated and intensified form. Maskell, Bathelt and Malmberg (2004) even call them “temporary cluster” using the concept to define a short-lived hotspot of intense knowledge exchange, network building and idea generation. It gathers heterogeneous participants in the same spot enabling them to bring together their specific knowledge through intensive interactions. Nevertheless, to date, we observed that the literature focusing on temporary clusters is limited. Notwithstanding, it requires growing attention for management science. In fact, the literature existing on temporary clusters, had asserted that these transient events are important for companies to access markets and knowledge pools in different part of the world. Therefore we consider temporary clusters as a significant vector for the building of trans-local business relations in common situations of incomplete knowledge and uncertainty. Besides, temporary clusters help developing global knowledge pipelines to benefit from outside knowledge.In this context, the paper will analyze a specific empirical case of temporary organization related to the tourism industry. Two arguments support this choice. On the one hand, as stated by Maskell et al. (2005), ‘identifying, selecting, approaching and interacting with new partners is a tricky and costly process' and, we think, even more in the tourism industry. Indeed, the tourism industry is structured by dispersed activities in nature, time and space that need to be combined and assembled dynamically. On the other hand, the tourism industry has been one of the most innovative activities related to the development of ICT, almost 50% of the innovations in the e-commerce activity come from e-tourism or m-tourism. Therefore, the analysis of a temporary cluster dedicated to this ‘dispersed' activity is particularly relevant.The paper will thus focus on such an event called Tourism@. This major event gathers the main actors of e-tourism and is dedicated to the usages of ICT in the tourism industry. It appears as a unique international trade fair in Europe dedicated to start up innovative companies, high tech SMEs, academic research, as well as large multinationals. Tourism@' specificity lies in the fact that each year, since 2001, the event includes the organization of a competition rewarding projects for their creativity and commitment in developing and implementing either new technologies or new uses for the tourism industry. The projects involved in this competition (175 since 2001) will be the basic elements of the temporal database we have build, in which the nature of the projects is extensively described (nature of the firm, of the technology, of the team, capabilities implemented, level of innovation...). In order to analyze the evolution of innovative activities in e-tourism, the initial step will be to characterize the projects through three main features: the market they address, nature of the technology and their innovative intensity. The study reveals that, each year, a main technology or a main innovation in terms of uses emerges showing some kind of self organization. Then, two points of the case study will be examined: first, the evolution of the dominant technology over time, and secondly, the diffusion of the emerging technology. Therefrom, the empirical study will aim at analyzing if temporary proximity allows the different actors from tourism industry to set up or mobilize knowledge and social links without requiring durable co-location. Furthermore, it will aim at identifying if, in a dynamic context of annual event, the repeated face to face temporary relations can result in trust and durable cooperation between different organizations. It might be expected that Tourism@ trade fair, in the role of a temporary cluster, enables to develop or implement innovative solutions, supports technology transfers and backs the creation of new markets as well as the fostering of horizontal and vertical relations between stakeholders.The paper is structured as follows. First section will investigate the theory field of temporary clusters and question in what extent a temporary cluster can be considered as a specific temporary organization regarding the interactions it support that lead to knowledge creation. Section two will present the Tourism@ case study; the methodology used and will develop the statistical analysis of the database. Lastly, the third section will be dedicated to the discussion of temporary clusters as a specific form of inter-firm organization that allows intensive exchange of knowledge.Knowledge creation; Temporary cluster; Tourism; Technological innovation

Citizens and Institutions as Information Prosumers. The Case Study of Italian Municipalities on Twitter

The aim of this paper is to address changes in public communication following the advent of Internet social networking tools and the emerging web 2.0 technologies which are providing new ways of sharing information and knowledge. In particular public administrations are called upon to reinvent the governance of public affairs and to update the means for interacting with their communities. The paper develops an analysis of the distribution, diffusion and performance of the official profiles on Twitter adopted by the Italian municipalities (comuni) up to November 2013. It aims to identify the patterns of spatial distribution and the drivers of the diffusion of Twitter profiles; the performance of the profiles through an aggregated index, called the Twitter performance index (Twiperindex), which evaluates the profiles' activity with reference to the gravitational areas of the municipalities in order to enable comparisons of the activity of municipalities with different demographic sizes and functional roles. The results show that only a small portion of innovative municipalities have adopted Twitter to enhance e-participation and e-governance and that the drivers of the diffusion seem to be related either to past experiences and existing conditions (i.e. civic networks, digital infrastructures) developed over time or to strong local community awareness. The better performances are achieved mainly by small and medium-sized municipalities. Of course, the phenomenon is very new and fluid, therefore this analysis should be considered as a first step in ongoing research which aims to grasp the dynamics of these new means of public communication

Patterns of dominant flows in the world trade web

The large-scale organization of the world economies is exhibiting increasingly levels of local heterogeneity and global interdependency. Understanding the relation between local and global features calls for analytical tools able to uncover the global emerging organization of the international trade network. Here we analyze the world network of bilateral trade imbalances and characterize its overall flux organization, unraveling local and global high-flux pathways that define the backbone of the trade system. We develop a general procedure capable to progressively filter out in a consistent and quantitative way the dominant trade channels. This procedure is completely general and can be applied to any weighted network to detect the underlying structure of transport flows. The trade fluxes properties of the world trade web determines a ranking of trade partnerships that highlights global interdependencies, providing information not accessible by simple local analysis. The present work provides new quantitative tools for a dynamical approach to the propagation of economic crises

User producer interaction in context: a classification

Science, Technology and Innovation Studies show that intensified user producer interaction (UPI) increases chances for successful innovations, especially in the case of emerging technology. It is not always clear, however, what type of interaction is necessary in a particular context. This paper proposes a conceptualization of contexts in terms of three dimensions – the phase of technology development, the flexibility of the technology, and the heterogeneity of user populations – resulting in a classification scheme with eight different contextual situations. The paper identifies and classifies types of interaction, like demand articulation, interactive learning, learning by using and domestication. It appears that each contextual situation demands a different set of UPI types. To illustrate the potential value of the classification scheme, four examples of innovations with varying technological and user characteristics are explored: the refrigerator, clinical anaesthesia, video cassette recording, and the bicycle. For each example the relevant UPI types are discussed and it is shown how these types highlight certain activities and interactions during key events of innovation processes. Finally, some directions for further research are suggested alongside a number of comments on the utility of the classification