Search results for "ECONOMICS"
showing 10 items of 14389 documents
A Generic Agent-Based Model of Historical Social Behaviors Change
2016
The primary theme of this chapter is trying to describe, discuss and understand how human societies change over time using agent-based modeling. Agents become a major paradigm of social simulation allow us to model the complex social phenomena under the bottom-up approach. Certainly one of the key points of the bottom-up approach is the emergence of macro level phenomena from micro level actions and interactions. The main objective of this work is to build a Virtual Social Laboratory, from Rafael Pla Lopez Social evolution model, in order to explore the social evolution of a set of artificial societies/agents that evolve within a grid of cells which are characterized by a level of natural r…
On the Macroeconomic Effect of Extortion: An Agent-Based Approach
2021
This work proposes an agent-based approach to study the effect of extortion on macroeconomic aggregates, despite the fact that there is little data on this criminal activity given its hidden nature. We develop a Bottom-up Adaptive Macroeconomics (BAM) model that simulates a healthy economy, including a moderate inflation and a reasonable unemployment rate, and test the impact of extortion on various macroeconomic signals. The BAM model defines the usual interactions among workers, firms and banks in labour, goods and credit markets. Subsequently, crime is introduced by defining the propensity of the poorest workers to become extortionists, as well as the efficiency of the police in terms of…
Towards an Agent-Based Model for the Analysis of Macroeconomic Signals
2020
This work introduces an agent-based model for the analysis of macroeconomic signals. The Bottom-up Adaptive Model (BAM) deploys a closed Walrasian economy where three types of agents (households, firms and banks) interact in three markets (goods, labor and credit) producing some signals of interest, e.g., unemployment rate, GDP, inflation, wealth distribution, etc. Agents are bounded rational, i.e., their behavior is defined in terms of simple rules finitely searching for the best salary, the best price, and the lowest interest rate in the corresponding markets, under incomplete information. The markets define fixed protocols of interaction adopted by the agents. The observed signals are em…
When Competition Is Pushed Too Hard. An Agent-Based Model Of Strategic Behaviour Of Referees In Peer Review
2013
This paper examines the impact of strategic behaviour of referees on the quality and efficiency of peer review. We modelled peer review as a process based on knowledge asymmetry and subject to evaluation bias. We built two simulation scenarios to investigate largescale implications of referee behaviour and judgment bias. The first one was inspired by “the luck of the reviewer draw” idea. In this case, we assumed that referees randomly fell into Type I and Type II errors, i.e., recommending submissions of low quality to be published or recommending against the publishing of submissions which should have been published. In the second scenario, we assumed that certain referees tried intentiona…
The effect of agglomeration economies and geography on the survival of accommodation businesses in Sicily
2021
The study explores the geographical pattern of the accommodation industry in the Italian insular region of Sicily, focusing on the determinants of the risk of market exit. We adopt a standard framework of business survival analysis where agglomeration economies play an important role. We then extend the analysis by considering the role of geography to explore whether the risk of market exit depends on nearness to desirable amenities. The geography is here measured by the distance from the coast and the altitude of the place where the firm is located. When we look at the entire population of accommodation firms that started between 2010 and 2014, we find evidence that the risk of failure inc…
Trade is not necessary for agglomeration to arise
2003
We develop a spatial general equilibrium model in which the absence of trade is an endogenous outcome and we show that trade is not a necessarycondition for agglomeration to arise. More precisely, extending the modeldeveloped by Ottaviano et al. [13], we show that equilibria without tradediffer significantly from those obtained in the presence of trade. Somewhatsurprisingly, equilibrium structures without trade are richer than those withtrade, since partial agglomeration becomes a feasible outcome. Equilibrianow depend on the ratio of mobile to immobile factors and an increase in thatratio triggers a process of spatial agglomeration.
Influence économique et concurrence au sein d'une agglomération
1986
La définition d'un indicateur de centralité do chaque zone d'une agglomération peut reposer sur l'utilisation de mesures d'accessibilité (type potentiel) et d'influence des zones considérées. (FUSTIER, GARLANDIERX ROUGET. - 1985). L'indicateur d'influence brute est présentement corrigé pour tenir compte de la concurrence interzones dans l'espace urbain. La définition et les propriétés générales dë l'indicateur d'influence effective sont présentées dans une première partie et illustrées sur un exemple numérique. Une seconde partie est consacrée à la présentation des résultats d'une application au cas de l'agglomération dijonnaise. Plusieurs simulations relatives à diverses répartitions des f…
Centres secondaires et recomposition économique des espaces urbains
2002
The object of this paper is to analyze the multicentric features of the Agglomeration of Dijon by studying the spatial organization of the economic activities and population. The study relates to the territory of the Agglomeration Community of Dijon (COMADI), which is composed of 16 towns. The space scale used is Iris-2000 zoning for the communes of more than 5000 inhabitants and the communal scale for the other towns belonging to the COMADI: the sample includes 114 observations. We use two databases available for two years (1990 and 1999): the SIRENE data for the employment by sectors of activities (ACTET10 and NAF700nomenclatures) and the data of the RGP for the population. We study the s…
Job contact networks, inequality and aggregate output
2005
In this paper we study the effects of social networks on wage inequality and aggregate production. In particular, we consider a simplified version of the model by Calvo'-Armengol and Jackson (2003), with good and bad jobs and skilled and unskilled workers. Our findings are: i) increasing the number of social links increases aggregate output and may reduce inequality; ii) given a number of social connections, output increases if the average distance among worker decreases; iii) a more mixed and well-integrated society, that is a society in which heterogeneous workers share social links, produces more output and less inequality than a society in which some workers are isolated, when productiv…
Determination of the modulus of elasticity of bone material by an acoustical approach at the forearm distinguishes women with and without vertebral f…
2002
The modulus of elasticity is a parameter characterizing fracture stability of bone independent of bone mineral density. Measurement of acoustical properties of the forearm by determination of the resonant frequency of the ulna in longitudinal direction as a function of sound transmission velocity after adjustment of the measuring result by ulna length yields information about the modulus of elasticity. It was the aim of this study to investigate whether this parameter may distinguish between subjects with and without vertebral fractures independent of bone mineral density. Fifty females (61.1 +/- 9.1 years) were enrolled into the study, 25 with, and 25 age-matched without prevalent osteopor…