1,720,959 research outputs found

    Econometric Tools for Detection of Collusion Equilibrium in the Industry

    Get PDF
    The article presents the notion of detection of overt or tacit collusion equilibrium in the context of choice of the appropriate econometric method, which is determined by the amount of information that the observer possesses. There has been shown one of the collusion markers coherent with an equilibrium of the proper model of strategic interaction – the presence of structural disturbances in the price process variance for phases of collusion and competition. The Markov Switching Model with switching of variance regimes has been proposed as a proper theoretical method detecting that type of changes without prior knowledge of switching moments. In order to verify the effectiveness of the method it has been applied to a series of lysine market prices throughout and after termination of its manufacturers’ collusion.explicit and tacit collusion, collusive equilibrium, cartel detection, lysine, price variance, Markov switching model.

    Cartel in the Indian cement industry: An attempt to identify it

    Get PDF
    This article is devoted to the problem of the detection of overt or tacit collusion equilibrium in the context of the choice of the appropriate econometric method, a choice that is determined by the amount of information that the observer possesses. The author addresses this problem in two steps. First, to provide a theoretical background, he uses a collusion marker based on structural disturbances in a price process'; variance. Then, he applies a Markov switching model with switching in variance regimes. The author considers this method adequate and coherent with the problem structure and the research objective, and useful for assessing the functionality of the collusion marker he uses. He uses the model to examine the Indian cement industry in the period 1994-2009 and finds some objective indications of collusion and competition phases. These phases are confirmed by certain historical facts as well as by numerous research articles

    Competition in a Wholesale Fuel Market—The Impact of the Structural Changes Caused by COVID-19

    No full text
    Liquid fuels obtained in refining crude oil are one of the most important energies in economic activity. The domestic wholesale market for liquid fuels is of decisive importance for price formation in the national economy. The noncompetitive behavior of the market players at this level of the distribution chain can significantly affect all downstream price levels and the producer–consumer surplus balance. Therefore, the competitiveness of this market should be screened and assessed regularly, especially when significant external factors change. This article attempts to evaluate the impact of structural changes on the global market of crude oil and energy products after the outbreak of the COVID-19 pandemic on the competitiveness of the wholesale fuel market in Poland. Using asymmetry of the reaction of product prices to changes in the prices of inputs as a marker of noncompetitive behavior and the NARDL model as a test specification, the price paths of market players before and after the occurrence of structural changes in the inputs’ processes were examined. Significant changes in the competitive behavior of players were revealed after the occurrence of structural changes at the beginning of the pandemic period in the year 2020. These changes may indicate enhanced competition and mitigation of potential market power abuse

    Machine Learning in Cartel Screening—The Case of Parallel Pricing in a Fuel Wholesale Market

    No full text
    The detection and deterrence of collusive agreements among firms, such as price-fixing cartels, remain pivotal in maintaining market competition. This study investigates the application of machine learning methodologies in the behavioral screening process for detecting collusion, with a specific focus on parallel pricing behaviors in the wholesale fuel market. By employing unsupervised learning techniques, this research aims to identify patterns indicative of collusion—referred to as collusion markers—within time series data. This paper outlines a comprehensive screening research plan based on the CRISP-DM model, detailing phases from business understanding to monitoring. It emphasizes the significance of machine learning methods, including distance measures, motifs, discords, and semantic segmentation, in uncovering these patterns. A case study of the Polish wholesale fuel market illustrates the practical application of these techniques, demonstrating how anomalies and regime changes in price behavior can signal potential collusion. The findings suggest that unsupervised machine learning methods offer a robust alternative to traditional statistical and econometric tools, particularly due to their ability to process large and complex datasets without predefined models. This research concludes that these methods can significantly enhance the detection of collusive behaviors, providing valuable insights for antitrust authorities

    Going Beyond Counting First Authors in Author Co-citation Analysis

    Get PDF
    The present study examines one of the fundamental aspects of author co-citation analysis (ACA) - the way co-citation counts are defined. Co-citation counting provides the data on which all subsequent statistical analyses and mappings are based, and we compare ACA results based on two different types of co-citation counting - the traditional type that only counts the first one among a cited work's authors on the one hand and a non-traditional type that takes into account the first 5 authors of a cited work on the other hand. Results indicate that the picture produced through this non-traditional author co-citation counting contains more coherent author groups and is therefore considerably clearer. However, this picture represents fewer specialties in the research field being studied than that produced through the traditional first-author co-citation counting when the same number of top-ranked authors is selected and analyzed. Reasons for these effects are discussed

    Variations on the Author

    Get PDF
    “Variations on the Author” discusses two of Eduardo Coutinho’s recent films (Um Dia na Vida, from 2010, and Últimas Conversas, posthumously released in 2015) and their contribution to the general question of documentary authorship. The director’s filmography is characterized by a consistent yet self-effacing form of authorial self-inscription: Coutinho often features as an interviewer that rather than express opinions propels discourses; an interviewer that is good at listening. This mode of self-inscription characterizes him as an author who is not expressive but who is nonetheless markedly present on the screen. In Um Dia na Vida, however, Coutinho is completely absent form the image, while Últimas Conversas, on the contrary, includes a confessional prologue that moves the director from the margins to the center of his films. This article examines the ways in which these works stand out in the filmography of a director who offers new insights into the notion of cinematic authorship

    Appropriate Similarity Measures for Author Cocitation Analysis

    Get PDF
    We provide a number of new insights into the methodological discussion about author cocitation analysis. We first argue that the use of the Pearson correlation for measuring the similarity between authors’ cocitation profiles is not very satisfactory. We then discuss what kind of similarity measures may be used as an alternative to the Pearson correlation. We consider three similarity measures in particular. One is the well-known cosine. The other two similarity measures have not been used before in the bibliometric literature. Finally, we show by means of an example that our findings have a high practical relevance.information science;Pearson correlation;cosine;similarity measure;author cocitation analysis

    Unreliability of markets – collusion of players. Detection methods in the light of the competition policy

    No full text
    This paper presents a review of a methodology of detection of overt or tacit collusion in the light of the modern competition policy based on the game theory. In this paper a consistent research procedure for identification and detection of collusion is proposed. It also systematizes the existing statistical and econometrical methods for the detection and assessment of collusion in industry according to such parameters as: result of a method, amount of statistical data necessary to apply a method, sensitivity to errors in an econometric model specification.</p

    The specifics of supply chain of medical kits product group in the context of using Enterprise Resource Planning class systems

    Get PDF
    Motivation: The article contains proposals of IT solutions supporting the management of selected links in the supply chain of Disposable Medical Kits product group.Aim: The aim of the article is the analysis of the distinctive features of the supply chain of Disposable Medical Kits product group (later referred to as DMK) in the context of managing such chain by means of IT solutions.Results: The first part of the article identifies distinctive features of the supply chain for this product group, which are of importance in the context of realizing the goals of social logistics of medical products supplies, as well as from the point of view of optimizing the management of the chain’s individual links. The second part of the article is devoted to presenting proposals of IT solutions supporting the management of supply chain, whose functionality are implied by the analysis conducted in the first part.</p
    corecore