Urban Area Development in Stochastic Cellular Automata

Urban is still an interesting topic to discuss whether in government or public studies. As economy grows in cities, many people are attracted to come to cities from villages to try their luck. In this paper, we investigated urban area development using von Thunen’s economic location theory. By using stochastic Cellular Automata which views land location as agents that will change their states in agriculture, industry, and service series, here we show how the urban areas dominated by economy, industry, and service activities develop to their surroundings and form areas with typical activities with urban area. Even for the farther agriculture area from urban center, von Thunen’s theory is still valid.von Thunen’s Theory, urban, Stochastic Cellular Automata, Markov matrices

Democratic Fair Allocation of Indivisible Goods

We study the problem of fairly allocating indivisible goods to groups of agents. Agents in the same group share the same set of goods even though they may have different preferences. Previous work has focused on unanimous fairness, in which all agents in each group must agree that their group's share is fair. Under this strict requirement, fair allocations exist only for small groups. We introduce the concept of democratic fairness, which aims to satisfy a certain fraction of the agents in each group. This concept is better suited to large groups such as cities or countries. We present protocols for democratic fair allocation among two or more arbitrarily large groups of agents with monotonic, additive, or binary valuations. For two groups with arbitrary monotonic valuations, we give an efficient protocol that guarantees envy-freeness up to one good for at least $1/2$ of the agents in each group, and prove that the $1/2$ fraction is optimal. We also present other protocols that make weaker fairness guarantees to more agents in each group, or to more groups. Our protocols combine techniques from different fields, including combinatorial game theory, cake cutting, and voting.Comment: Appears in the 27th International Joint Conference on Artificial Intelligence and the 23rd European Conference on Artificial Intelligence (IJCAI-ECAI), 201

Solving Optimization Problems by the Public Goods Game

This document is the Accepted Manuscript version of the following article: Marco Alberto Javarone, ‘Solving optimization problems by the public goods game’, The European Physical Journal B, 90:17, September 2017. Under embargo. Embargo end date: 18 September 2018. The final, published version is available online at doi: https://doi.org/10.1140/epjb/e2017-80346-6. Published by Springer Berlin Heidelberg.We introduce a method based on the Public Goods Game for solving optimization tasks. In particular, we focus on the Traveling Salesman Problem, i.e. a NP-hard problem whose search space exponentially grows increasing the number of cities. The proposed method considers a population whose agents are provided with a random solution to the given problem. In doing so, agents interact by playing the Public Goods Game using the fitness of their solution as currency of the game. Notably, agents with better solutions provide higher contributions, while those with lower ones tend to imitate the solution of richer agents for increasing their fitness. Numerical simulations show that the proposed method allows to compute exact solutions, and suboptimal ones, in the considered search spaces. As result, beyond to propose a new heuristic for combinatorial optimization problems, our work aims to highlight the potentiality of evolutionary game theory beyond its current horizons.Peer reviewedFinal Accepted Versio

Survival of the Fittest in Cities: Agglomeration, Selection, and Polarisation

Empirical studies consistently report that labour productivity and TFP rise with city size. The reason is that cities attract the most productive agents, select the best of them, and make the selected ones even more productive via various agglomeration economies. This paper provides a microeconomically founded model of vertical city differentiation in which the latter two mechanisms (`agglomeration' and `selection') operate simultaneously. Our model is both rich and tractable enough to allow for a detailed investigation of when cities emerge, what determines their size, and how they interact through the channels of trade. We then uncover stylised facts and suggestive econometric evidence that are consistent with the most distinctive equilibrium features of our model. We show, in particular, that larger cities are both more productive and more unequal (`polarised'), that inter-city trade is associated with higher income inequalities, and that the proximity of large urban centres inhibits the development of nearby cities.entrepreneur heterogeneity, firm selection, agglomeration, income inequalities, urbanization, urban systems

Evacuation time estimate for a total pedestrian evacuation using queuing network model and volunteered geographic information

Estimating city evacuation time is a non-trivial problem due to the interaction between thousands of individual agents, giving rise to various collective phenomena, such as bottleneck formation, intermittent flow and stop-and-go waves. We present a mean field approach to draw relationships between road network spatial attributes, number of evacuees and resultant evacuation time estimate (ETE). We divide $50$ medium sized UK cities into a total of $697$ catchment areas which we define as an area where all agents share the same nearest exit node. In these catchment areas, 90% of agents are within $5.4$ km of their designated exit node. We establish a characteristic flow rate from catchment area attributes (population, distance to exit node and exit node width) and a mean flow rate in free-flow regime by simulating total evacuations using an agent based `queuing network' model. We use these variables to determine a relationship between catchment area attributes and resultant ETE. This relationship could enable emergency planners to make rapid appraisal of evacuation strategies and help support decisions in the run up to a crisis.Comment: 6 pages, 8 figure

Managing induced tourism image: Relational patterns and the life cycle

The tourism image is an element that conditions the competitiveness of tourism destinations by making them stand out in the minds of tourists. In this context, marketers of tourism destinations endeavour to create an induced image based on their identity and distinctive characteristics.A number of authors have also recognized the complexity of tourism destinations and the need for coordination and cooperation among all tourism agents, in order to supply a satisfactory tourist product and be competitive in the tourism market. Therefore, tourism agents at the destination need to develop and integrate strategic marketing plans.The aim of this paper is to determine how cities of similar cultures use their resources with the purpose of developing a distinctive induced tourism image to attract tourists and the extent of coordination and cooperation among the various tourism agents of a destination in the process of induced image creation.In order to accomplish these aims, a comparative analysis of the induced image of two cultural cities is presented, Girona (Spain) and Perpignan (France). The induced image is assessed through the content analysis of promotional brochures and the extent of cooperation with in-depth interviews of the main tourism agents of these destinations.Despite the similarities of both cities in terms of tourism resources, results show the use of different attributes to configure the induced image of each destination, as well as a different configuration of the network of tourism agents that participate in the process of induced image creation

Explaining the size distribution of cities: X-treme economies

The methodology used by theories to explain the size distribution of cities is contrived in that it takes an empirical fact and works backward to first obtain a reduced form of a model, then pushes this reduced form back to assumptions on primitives. The induced assumptions on consumer behavior, particularly about their ability to insure against the city-level productivity shocks in the model, are untenable. With either self insurance or insurance markets, and either an arbitrarily small cost of moving or the assumption that consumers do not perfectly observe the shocks to firms' technologies, the agents will never move. Equilibrium implies a uniform distribution of agents. Even without these frictions, our analysis yields another equilibrium with insurance that gives exactly the same utility level to consumers as the equilibrium studied in the literature, but where consumers never move. Thus, insurance is a substitute for movement. Even aggregate shocks are insufficent to generate consumer movement, since consumers can borrow and save. We propose an alternative class of models, involving extreme risk against which consumers will not insure. Instead, they will move.Zipf's Law; Gibrat's Law; Size Distribution of Cities; Extreme Value Theory