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We propose a data-driven machine learning approach to flag bid-rigging cartels in the Brazilian road maintenance sector. First, we apply a clustering algorithm to group the tenders based on their attributes. Second, we use the labels created by the clustering algorithm as a target variable to predict them using a classifier. We rank the predictors according to their relevance to decrease the number of false positive (detect cartel when it does not exist) and false negative (do not detect cartel when it does exist) predictions. Our results shed light on the need to use a range of predictors to recognize the vast profile of strategies practiced by bid-rigging cartels, such as misleading competitive dynamics, bid combination, and cover bidding behavior. Our method can improve cartels' deterrence in different economic sectors, especially when labeled data are not available. In a controlled environment with a simulated dataset, the overall average accuracy of the algorithm is 99.33%. In a real-world cartel case with a labeled dataset, the overall average accuracy is 80.25%. When applied to the road maintenance dataset, our model identified a group containing 273 (31% of the total) suspicious tenders. We conclude by offering a policy prescription discussion for antitrust authorities.

This paper aims to analyse firms' location decisions when faced with Brexit. We combine evolutionary game theory and spatial agent‐based simulation approaches with input–output analysis to evaluate two different sectors: (i) crop and animal production; (ii) financial service activities. We separate the European Union in manifold regions and consider the following factors in the decision making: (i) market potential; (ii) productive integration; (iii) labour costs and (iv) displacement cost. Firms assign weights to each of these factors. Our results suggest that in traditional sectors firms tend to seek unsaturated markets. In sectors related to services, the greater the uncertainty, the greater the likelihood that firms will move. Este articulo tiene por objeto analizar las decisiones de localizacion de las empresas como respuesta a Brexit. En el articulo se combina la teoria de juegos evolutivos y los enfoques de simulacion espaciales basados en agentes con el analisis de input–output, con el fin de evaluar dos sectores diferentes: i) la produccion de cultivos y animales; y ii) las actividades de los servicios financieros. Se desagrego la Union Europea en multiples regiones y se consideraron los siguientes factores en la toma de decisiones: i) el potencial de mercado; ii) la integracion productiva; iii) los costos de la mano de obra y iv) el costo del desplazamiento. Las empresas asignan un valor ponderado a cada uno de estos factores. Los resultados sugieren que en los sectores tradicionales las empresas tienden a buscar mercados no saturados. En los sectores relacionados con los servicios, cuanto mayor sea la incertidumbre, mayor sera la probabilidad de que las empresas se trasladen. 本稿では、ブレグジット問題に直面した際の企業の立地決定を分析する。我々は、進化ゲーム理論と空間的エージェント・ベース・シミュレーションのアプローチを産業連関分析と組み合わせて、農畜産物製造と金融サービス業の2つの異なるセクターの評価を行う。欧州連合を多様体の地域(manifold region)に分割し、1)市場としての可能性、2)生産性統合、3)人件費、4)移転費用、の意思決定における4つの因子について検討する。企業は以上の因子のいずれも重要視している。結果から、伝統的セクターの企業は飽和していない市場を探す傾向があることが示唆される。サービス業に関連するセクターでは、不確実性が大きければ大きいほど企業の移転の確率が高くなる。

Esta pesquisa faz parte de uma experiência cartográfica vivida enquanto habitante e pesquisador, cujo objetivo foi apreender e refletir sobre as paisagens às margens da BR- 386, entre os municípios de Triunfo e Montenegro, a oeste da Região Metropolitana de Porto Alegre/RS (RMPA). Nesse contexto de estudo, próximo ao complexo industrial do III Pólo Petroquímico, são desenvolvidas atividades de comércio, serviço, extrativismo, silvicultura, indústria, logísticas, monoculturas, entre outras, que dão a ver as complexidades de um intenso processo de urbanização da paisagem metropolitana engendrado nas últimas décadas. Através da abordagem teórico-metodológica da narrativa, a paisagem é aqui entendida a partir de uma perspectiva contemporânea, onde as paisagens são um acontecer de vários aconteceres, visíveis e invisíveis, entrelaçados ao longo do tempo e do espaço, em meio a práticas cotidianas e histórias das e dos habitantes. A cartografia nesta pesquisa é entendida tanto como cartografia da ação social quanto como cartografia sentimental. Sendo assim, não se trata de representar uma paisagem emoldurada, mas de dar atenção aos materiais e às forças que se movem em meio à paisagem. Seguindo os rastros de dois grandes projetos de escala metropolitana e regional, a ampliação da BR-386 e o Aterro Industrial na localidade de Pesqueiro, produzo dois ensaios cartográficos inspirados pelas operações metodológicas da montagem, cuja disposição de fragmentos de um acervo narrativo em movimento faz emergir sintomas de uma paisagem arruinada. É através desses sintomas que busco emaranhar as estratégias dos empreendimentos, suas arenas políticas, as operações que mobilizam e seus impactos, ao mesmo tempo em que disponho as experiências cotidianas de vizinhas e vizinhos que narram sobre modos de resolver a vida que escapam e/ou interpelam as lógicas desse desenvolvimento metropolitano. Chego, por fim, à "paisagem brutalista" e à "paisagem de sacrifício", duas pistas que deslocam a paisagem da sua tradicional objetificação e convocam seu entendimento enquanto expressão de uma permanente disputa de forças, a ser incorporada nos estudos urbanos e regionais. This research is part of a cartographic experience lived as an inhabitant and researcher, whose objective was to apprehend and reflect on the landscapes on the roadsides of the BR-386 highway, between the municipalities of Triunfo and Montenegro, west of the Metropolitan Region of Porto Alegre/RS (RMPA). In this context of study, adjacent to the industrial structure of the III Petrochemical Complex, practices such as commerce, service, extractivism, forestry, industry, logistics and monoculture activities are developed, which reveal the complexities of an intense process of urbanization of the metropolitan landscape engendered along recent decades. Through a theoretical-methodological approach of the narrative, the landscape is understood here from a contemporary perspective, where landscapes are a happening of several happenings, visible and invisible, entangled over time and space, in the midst of everyday practices and stories of the inhabitants. The cartography in this research is understood both as a cartography of social action and as a sentimental cartography. Therefore, it is not a question of representing a framed, static landscape, but of paying attention to the materials and forces that act throughout a landscape. Following in the trails of two projects on a metropolitan and regional scale, the expansion of the BR-386 highway and the Industrial Landfill in the locality of Pesqueiro, I produce two cartographic essays inspired by the methodological operations of montage, whose arrangement of fragments of an ongoing narrative collection brings out symptoms of a ruined landscape. It is through these symptoms that I seek to entangle the strategies of the enterprises, their political stages, the operations they mobilize and their impacts, at the same time that I present the daily experiences of neighbors who tell stories about ways of solving life that escape and/or question the logics of this metropolitan development. Finally, I arrive at "brutalist landscape" and "sacrifice landscape", two landscape sayings that displace landscape from its traditional objectification and summon its understanding as an expression of a permanent dispute of forces, to be embodied in urban and regional studies.

Estima-se, segundo o Conselho Federal de Medicina (2015), que 600 mil novos casos de sepse ocorrem a cada ano no Brasil, com custo de US$9,6mil por paciente

This paper combines evolutionary game theory and input–output analysis to assess firms’ strategic location choice. To evaluate the model, firms competed in the automotive sector of Mercosur. To decide where to locate, the following exogenous factors were considered: potential market; local productive interdependence; tax incentive; and macroeconomic stability. Firms assigned weights to these factors in their location decision. It was found that competing in a market where there is tax exemption is not always an ideal location decision, contradicting the common-sense assumption by which there is a direct relationship between government incentives and the attractiveness of regions.

We aim to evaluate two different econometric screens for identifying anti-competitive behavior in the fuel retail market: (i) The Markov-Switching GARCH (MS-GARCH) Models; (ii) The Local Gaussian Correlation (LGC) approach. Using the gasoline cartel judged and condemned in Brasilia as a benchmark, our results indicate that the LGC model, based on the correlation of the resale price margin and price variability, may provide a biased likelihood as well as an incorrect identification of cartel behavior over time. The MSGARCH model, based only on the log deviation of the average gasoline sales price, showed better accuracy in cartel detection.

This article aims to analyze the strategic decision about firms location choice faced with the uncertainty surrounding Brexit. We combine Evolutionary Game Theory (EGT) and spatial Agent-based Simulation (ABS) approaches with input-output analysis. Firms are competing in two different sectors: (a) crop and animal production; (b) financial service activities. We separate the European Union in manifold regions and consider the following factors in the decision making: (i) market potential; (ii) productive integration; (iii) labor costs and (iv) displacement cost. Firms assign weights to each of these factors. Our results suggest that in traditional sectors firms tend to seek unsaturated markets. In sectors related to services, the greater the uncertainty, the greater the likelihood that firms will move.

We propose both a well-mixed and spatially-structured evolutionary game to analyze the competitive behavior of retail firms in duopolistic markets. Firms from two different populations (high/low efficiency) compete and the available strategies are (i) Profit or (ii) Revenue maximization. Under bounded-rationality assumptions, firms can update their behavior through dynamic learning mechanisms. In addition to a replicator dynamics approach, we develop an Agent-based model to increase realism and to capture possible spatial effects on firms’ strategic behavior. A convergence between the methods is observed and, given specific conditions, Revenue maximization may corresponds to an Evolutionary Stable Strategy (ESS).

In this article, we propose a Snowdrift Game with costly punishment in a spatial-structured two-population arrangement. In order to generate the results, we use the Agent Based Simulation (ABS) model. The numerical simulations as well as the dynamics observed in the ABS are analyzed and discussed. In contrast to a single structured population, the P strategy survives only in one of the cases analyzed. The competitive dynamics and the evolutionary equilibrium of the game arranged in two spatial-structured populations differs from the standard behavior detected in the literature. Thus, we can observe: (i) entire populations of C and D; (ii) the coexistence of C and P in the same population for the case in which the cost for the benefit of cooperating is low.