Teses / dissertações sobre o tema "Platformes Numériques"
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Darlas, Pierre-François. "Digital Platforms Strategies and Regulation : Essays in Industrial Organization". Electronic Thesis or Diss., Institut polytechnique de Paris, 2024. http://www.theses.fr/2024IPPAT035.
Texto completo da fonteThis thesis focuses on market power in digital markets. It aims at providing insights to policy makers, by allowing them to understand digital platforms' strategies and their impact on market outcomes.The first chapter theoretically examines platforms' business model decisions, and their impact on innovation. In equilibrium, platforms can differentiate in business model, potentially allowing them to innovate more thanks to a Schumpeterian effect of business model differentiation. We identify that business model can be a source of distortion, and that policy makers should take it into account in attempting to design innovation stimulating policies.The second chapter theoretically studies the "AdTech" stack contestability. Its results indicate that vertical integration between an incumbent "AdTech" stack with a downstream display advertising platforms (e.g. Google and YouTube) is a way to successfully reduce "AdTech" contestability. I discuss the efficiency of online advertising restrictions, in the spirit of European Union TV regulations, in tackling issues related to such integration and protecting end users from excessive exposure to online advertising.The third chapter empirically inspects the effect of products value assessment information provision by online auction platforms. Our findings indicate that, holding intrinsic object value constant, higher experts estimates increase buyers valuation for the good. Despite potential conflicts of interest stemming from the platform's dual role as matchmaker and advisor, our results show that expert estimates are influential even when potentially overinflated. This study underscores the critical role of platform-provided information in enhancing market efficiency
Thebaudin, Guillaume. "Regulation of Digital Platforms : Essays in Industrial Organization". Electronic Thesis or Diss., Institut polytechnique de Paris, 2023. http://www.theses.fr/2023IPPAT021.
Texto completo da fonteThis thesis addresses issues related to market power in digital markets. It aims at improving the understanding of digital platforms' governance decisions and their resulting market outcomes.The first chapter theoretically explores the effect of interoperability on competition between two ad-financed platforms, allowing for endogenous multi-homing of consumers. Interoperability emerges in equilibrium if the value of multi-homers relative to single-homers is sufficiently low for advertisers. This equilibrium level of interoperability is however misaligned with social welfare maximization. In markets dominated by one platform, mandating interoperability between the asymmetric platforms is not always socially optimal.The second chapter empirically investigates the issue of self-preferencing on hybrid platforms, using web-scraped data from the Amazon marketplace. It appears that Amazon makes the visibility of offers of third-party suppliers in the "buybox" dependent on prices on competing marketplaces. Amazon's own offers are however visible regardless of their competitiveness. Furthermore, the absence of seller recommendations makes recommendations to related products more effective and Amazon tends to steer consumers in these situations more often to products it sells itself. Overall, this illustrates how self-preferencing can appear in subtle forms.The last chapter theoretically examines the incentives of hybrid platforms to invest in screening tools to detect and delist illegal third-party products. Whereas platforms engage in screening to the extent that it accommodates entry, more vertically integrated platforms tend to screen less due to the business-stealing effect it induces. Additionally, platforms conducting screening charge higher commission fees to sellers. This strategic complementarity can lead to a negative relationship between platforms' degree of vertical integration and the level of commission fees.These three chapters highlight the complex nature of digital markets and the need for regulatory intervention to be carefully calibrated
Raizonville, Adrien. "Regulation and competition policy of the digital economy : essays in industrial organization". Electronic Thesis or Diss., Institut polytechnique de Paris, 2021. http://www.theses.fr/2021IPPAT028.
Texto completo da fonteThis thesis addresses two issues facing regulators in the digital economy: the informational challenge generated by the use of new artificial intelligence technologies and the problem of the market power of large digital platforms. The first chapter of this thesis explores the implementation of a (costly and imperfect) audit system by a regulator seeking to limit the risk of damage generated by artificial intelligence technologies as well as its cost of regulation. Firms may invest in explainability to better understand their technologies and, thus, reduce their cost of compliance. When audit efficacy is not affected by explainability, firms invest voluntarily in explainability. Technology-specific regulation induces greater explainability and compliance than technology-neutral regulation. If, instead, explainability facilitates the regulator's detection of misconduct, a firm may hide its misconduct behind algorithmic opacity. Regulatory opportunism further deters investment in explainability. To promote explainability and compliance, command-and-control regulation with minimum explainability standards may be needed. The second chapter studies the effects of implementing a coopetition strategy between two two-sided platforms on the subscription prices of their users, in a growing market (i.e., in which new users can join the platform) and in a mature market. More specifically, the platforms cooperatively set the subscription prices of one group of users (e.g., sellers) and the prices of the other group (e.g., buyers) non-cooperatively. By cooperating on the subscription price of sellers, each platform internalizes the negative externality it exerts on the other platform when it reduces its price. This leads the platforms to increase the subscription price for sellers relative to the competitive situation. At the same time, as the economic value of sellers increases and as buyers exert a positive cross-network effect on sellers, competition between platforms to attract buyers intensifies, leading to a lower subscription price for buyers. The increase in total surplus only occurs when new buyers can join the market. Finally, the third chapter examines interoperability between an incumbent platform and a new entrant as a regulatory tool to improve market contestability and limit the market power of the incumbent platform. Interoperability allows network effects to be shared between the two platforms, thereby reducing the importance of network effects in users' choice of subscription to a platform. The preference to interact with exclusive users of the other platform leads to multihoming when interoperability is not perfect. Interoperability leads to a reduction in demand for the incumbent platform, which reduces its subscription price. In contrast, for relatively low levels of interoperability, demand for the entrant platform increases, as does its price and profit, before decreasing for higher levels of interoperability. Users always benefit from the introduction of interoperability
Quiroga, Cortes Catherine. "La fabrique de l'information locale à l'aune des plateformes socio-numériques". Electronic Thesis or Diss., Université de Toulouse (2023-....), 2024. http://www.theses.fr/2024TLSES001.
Texto completo da fonteThis thesis focuses on the production process of journalistic information on a local scale and in the light of socio-media platforms. The production of journalistic information is considered here as a socio-discursive practice that can be invested by actors located beyond the professional journalistic group. This work questions the methods of intervention of socio-digital networks in the 'local information factory' and their impact on the relational dynamics which drive it. In order to open the black box of local information making, we rely on the analysis of controversies. Since they unfold in a territorial context, controversies offer researchers a more or less well-defined spatio-temporal framework. We thus construct a hybrid methodological approach inspired by the mapping of controversies and carry out a comparative study of two controversies deployed around land development projects: an offshore wind farm and the construction of an Amazon logistics center. The hybridity of the approach concerns both the collection of empirical data (30 semi-structured interviews, nearly 1500 press articles, more than 5000 tweets and Facebook publications, observations carried out offline and online, collection of documentation) and the analytical methods (inductive thematic coding, textometric analysis, reconstruction of the trajectory of controversies). Our study demonstrates that Facebook generalizes access to the production of local information to the extent that it empowers users to exercise practices that are part of the process of producing and circulating information. However, our work also highlights the significant constraints that weigh on users who invest in social-media arenas, often unknown or poorly understood by many. The plurality of investment modalities of said platforms highlights significant disparities between the actors involved in the controversies studied and in their possibilities of dominating the narrative on the events, facts or issues surounding the controversies. Finally, our study highlights the centrality of regional and local media in the 'local information factory'. If the latter are still heavily dependent on social-media platforms for the distribution of their editorial content, they preserve a symbolic legitimacy with a large audience in their publishing territories
Muñoz, Acevedo Angela. "Public policy in the digital age : evidence from telecommunications and digital platforms". Electronic Thesis or Diss., Institut polytechnique de Paris, 2022. http://www.theses.fr/2022IPPAT006.
Texto completo da fonteThis doctoral thesis studies questions relevant for public policies in the context of the digital transformation of the world economy. It examines new situations and public interventions on the telecommunications and digital sectors affecting people’s mobility and their integration in the digital economy. It is divided into three chapters.The first chapter assesses the impact of the roaming regulation implemented in the European Union on mobile operators’ revenues and retail prices. The results suggest that the regulation decreased mobile operator’s revenues per user, while having no impact on prices during the latest phase of the regulation. Thus, we find no evidence of a strategic reaction to the regulation by mobile operators.The second chapter studies the determinants of fiber entry by telecommunications’ operators and evaluates the efficiency and the impact of a State aid plan for the deployment of ultra-fast broadband networks in France. On the determinants of fiber entry, we identify market size and income as important characteristics that increase the attractiveness of local markets. Moreover, we find evidence of a strong geographic dependence in the fiber entry process, the presence of a replacement effect from the legacy copper network and an increase in the ease of entry over time. On the evaluation of the plan, we find that it was overall efficient and helped increase fiber coverage in aided municipalities at the early stages of fiber diffusion.The third chapter studies challenges of transport policy in the presence of ride-hailing platforms. Specifically, it assesses the impact of these platforms on the incidence of drunk-driving fatal crashes and fatalities, using Chile as a case study. Moreover, it studies heterogeneous effects in fatalities by gender. The results suggest that, ride-hailing platforms significantly reduced drunk-driving fatal crashes and fatalities in Santiago. In particular, it helped decrease the number of female passengers’ fatalities and the number of male drivers’ fatalities at night
Kumar, Anaya. "IT identity and employee advocacy platforms use : a mixed-method approach". Electronic Thesis or Diss., université Paris-Saclay, 2024. https://www.biblio.univ-evry.fr/theses/2024/interne/2024UPASI013.pdf.
Texto completo da fonteIn recent years, we see a shift from traditional physical workplaces to hybrid and remote environments, leading to the adoption of digital workplaces (Malhotra, 2021). Despite their instrumental value such as increased employee productivity, digital workplaces present challenges including employee disconnection and disengagement (Qin & Men, 2022). To address this, organizations attempt to strengthen organizational identification and engagement using people-centric digital workplace platforms. Given the critical role of identity in fostering engagement and performance, in this thesis we examine the phenomenon of IT identity, which refers to positive self-identification with information technology (ITID) (Carter, 2020).Our study examines how employees' use of a digital workplace platform called Employee Advocacy (EA) platform- which enables employees to defend, support, or recommend their organization to their networks- is influenced by the their ITID perceptions. EA fosters re-identification with the organization and is increasingly recognized for its ability to leverage employees' credibility to enhance brand reputation, extend reach, and drive business growth (Silbermann, 2021). While the literature on EA covers its definition and purpose, few studies—especially within Information Systems (IS)—have examined how ITID might impact platform use that facilitate EA programs. This thesis addresses that gap by theorizing the antecedents and outcomes of ITID for the EA platform use context. We do this via two essays.The first essay examines the existence of ITID within EA platforms and leverages ITID theory and IS continuous use and acceptance literature to theorize the two user experience antecedents (functional and emotional) of ITID. The second essay also leverages ITID theory and needs-affordances features perspective to theorize how ITID influences key outcomes of EA platforms- conceptualizing digital employee engagement (DEE), which includes digital employee advocacy (DEA) and digital employee connectedness (DEC). Both essays use a sequential mixed-method approach, starting with a quantitative study followed by a qualitative study. The first study within both essays uses employee reviews of EA platforms as its data (N=1360) to test the theoretical models, while the second study within both essays uses semi-structured interview data obtained from experts of EA platform (N=12) to provide validation and identify boundary conditions to our theorized models.The findings confirm our theorized model in essay one, however, it is moderated by factors such as role identity, social media self-efficacy, and structured platform launch. The results of the second essay also confirm our model. However, we propose that these relationships are moderated by boundary conditions such as change management reinforcement, proactive leaders, organization image. In particular, the essays advance our understanding of IT identity when using digital workplace technologies and its relevance in achieving both humanistic outcomes of digital employee connectedness and instrumental goals of digital employee advocacy. The findings also offer several practical insights for organizations seeking to implement and optimize EA platforms to enhance digital employee engagement through the introduction of the digital workplace
Malardé, Vincent. "Économie collaborative et régulation des plateformes numériques". Thesis, Rennes 1, 2019. http://www.theses.fr/2019REN1G006.
Texto completo da fonteFacilitated by peer-to-peer platforms, the sharing economy has become part of the French way of life. Airbnb, Blablacar, Leboncoin... these platforms are now well known in France. This thesis aims to provide more elements, both theoretical and empirical, to inform the current debates around these platforms. This thesis work begins by using survey data to measure the importance of the use of collaborative platforms in France, and to establish the socio-economic characteristics of users. Then this thesis focuses on the dynamics of developing a collaborative platform,through the example of the French home-to-work ride-sharing platform, iDVROOM. The objective is to study the complementary role of network effects, spatial effects and community effects on the development of the platform. The rest of this thesis focuses on the competition between the short-term rental platform Airbnb and the hotel industry in Paris. The effect of the density of hosts on the collaborative platform on the price charged by an hotel is the subject of a firstempirical study, before being modeled in a theoretical way to discuss the possible effects of a set of alternative regulations of the platform’s activity. Finally, competition between two platforms is analysed when they have the possibility of implementing tariff discrimination strategies designed to encourage supplier exclusivity. The conclusion develops the implications of these results forpolicy makers, platforms and academic research
Andres, Raphaela. "Empirical essays on policy interventions in the digital economy". Electronic Thesis or Diss., Institut polytechnique de Paris, 2024. http://www.theses.fr/2024IPPAT016.
Texto completo da fonteThis thesis empirically investigates policy and managerial interventions in the digital economy and analyses their effectiveness and potential side effects.The first chapter uncovers an unintended policy effect of a public support scheme for firms in economically lagging regions in Germany. It exploits variation in the eligibility and the size of potential investment subsidies of firms in order to analyse the relationship with the firms' propensity to adopt cloud services. The empirical results demonstrate that the higher the potential subsidy for investments, the lower the incentive for firms to adopt cloud services. This unintended policy effect is highly relevant for policy makers, as the adoption of cloud services has been linked to various benefits on the firm as well as on the aggregate economy level.The second chapter analyses the pioneering online hate speech regulation on the social media platform X. It exploits the regulation, the German Network Enforcement Act, in a quasi-experimental approach to measure the causal impact of the law on the prevalence of hateful content in a target group of the German-speaking segment of X. The results imply a significant and robust decrease in the intensity and volume of hate speech in tweets tackling sensitive migration and religion related topics. Importantly, tweets tackling other topics as well as the tweeting style of users are not affected by the regulation, which is in line with its aim. This chapter highlights that legislation for combating harmful online content can significantly reduce the prevalence of hate speech and contributes to understanding the perspective implications of the European Digital Services Act.The third chapter investigates mechanisms of the Creator Economy, which capitalizes on a multi-sided business model, connecting content creators, users, and (sometimes) advertisers. Matching the needs of these different stakeholders is a complex challenge, as evidenced by the impact of the YouTube “Adpocalypse” in 2017, when major advertisers fled YouTube due to concerns about their ads appearing alongside objectionable content. This chapter exploits YouTube's subsequent content moderation efforts following the Adpocalypse to measure the cross-platform responses of content creators and content consumers on Patreon. Focusing on content creators that multi-home on YouTube and Patreon, the theoretical model and empirical evidence of this chapter confirm that these content creators respond strategically and shift their efforts toward Patreon. As a result, consumers also increase their use of Patreon through memberships, comments, and likes. However, we also find that YouTube's content moderation and the shift by content creators and consumers that follows, results in an increase in toxicity on Patreon. These findings indicate that governance rules of a single platform cannot be looked at in isolation. Instead, platform managers and policy makers need to consider potential cross-platform reactions of all stakeholders.The three chapters of this thesis demonstrate that interventions in the digital economy can be effective in shaping online discussions, but digital particularities such as rapidly changing technologies and substitution effects need to be carefully considered
Viotto, Da Cruz Jordana. "The Economics of Crowdfunding : Entrepreneurs’ and Platforms’ Strategies". Thesis, Sorbonne Paris Cité, 2017. http://www.theses.fr/2017USPCD030/document.
Texto completo da fonteCrowdfunding platforms allow entrepreneurs to directly contact small investorsand potential consumers to help them finance their ideas. This thesis dedicates tounderstanding the dynamics of these platforms from an economic perspective. We areparticularly interested in comprehending the entrepreneurs’ and platforms’ strategies in thismarket. This thesis is composed by four scientific articles organized in two parts. The firstpart focuses on analyzing the crowdfunding market dynamics and the design and strategiesof crowdfunding platforms. In the first article (Chapter 1), we discuss the characteristic ofcrowdfunding platforms based on the theory of two-sided markets. We underline thestrategies platforms use to perform their coordinating role of the market. Based on thecurrent literature, we analyze the incentives and disincentives of entrepreneurs andinvestors to participate on these platforms as well as the instruments to reduce informationasymmetries and the potential biases on the investors’ screening process in relationship toentrepreneurs’ physical characteristics. The second article (Chapter 2) examines thechallenge of crowdfunding platforms to balance “quantity” and “quality” on both sides ofthe market, and at the same time accounting for competition. In particular, we examinehow a strategy to attract more entrepreneurs to one side can reduce platforms’ thecompetitive advantage and potentially deteriorate users’ experience. The second part of thethesis is devoted to the incentives and disincentives for entrepreneurs to join crowdfundingplatforms. In the first article of the second part (Chapter 3 of this thesis), we empiricallydemonstrate the informational value of crowdfunding for entrepreneurs. Before launchinga new product in a market, entrepreneurs face high uncertainties that can be reduced withthe “feedback” received from crowdfunding campaigns. Therefore, the informational valueof crowdfunding serves as an additional incentive to entrepreneurs besides obtainingfinancial support for their ideas. The fourth and last article aims at pointing outdisincentives to join platforms, in particular how the need of allocating scarce time andattention to campaigns may discourage some entrepreneurs from seeking this alternative.To conclude, we summarize the implications of the main findings and suggest avenues forfuture research
Li, Yaxin. "Trois essais sur l'économie numérique et la concurrence entre plateformes". Electronic Thesis or Diss., Toulouse 1, 2023. https://publications.ut-capitole.fr/id/eprint/49435/.
Texto completo da fonteIn Chapter 1, I develop a dynamic model where two data-driven platforms compete for users' attention. The quality of the service on each platform improves as more user data is available. At each period, platforms choose between current monetization through advertisement, or the accumulation of more user and therefore more data, in the future. Accordingly, I relate the market outcomes in equilibrium to platforms' initial market shares and data productivities. I show that market co-participation prevails when data productivities of both platforms are small. Market tipping is more likely to occur when one of the platforms has a large data productivity and enjoys a large initial market share. I also explore the effects of compulsory data sharing. Market tipping is less likely to occur with data sharing. Besides, data sharing by both platforms, or by the platform with a large advantage of data productivity increases consumers' surplus. In chapter 2, motivated by several examples, including Internet of Things patent licensing, we analyze a model where one or more complementary platforms choose prices for a group of downstream devices that exhibit network externalities. We show how prices depend on each device's Katz-Bonacich (or eigenvector) centrality in a network defined by the demand externalities, and how the relevant network differs for an ecosystem monopolist, a social planner, or a group of complementary platforms. For the latter case, we revisit Cournot's analysis of complementary monopolies and show that in our setting, it is possible for the total price of a particular device to decline when the number of monopoly platforms increases. Finally, we analyze a partial merger that leaves complementary monopolies on just one side of a platform, producing a novel tradeoff between internalizing double marginalization and externalizing network effects. Oevrall, this study offers a tractable model of multi-product ecosystems, and contributes to the two-sided market literature by analyzing complementary platforms in a general multi-sided market. In chapter 3, I study a strategic network game of search, where $M$ retailers sell a product with unknown quality in a competing market. Consumers in the network choose between search and free riding, and choose to adopt or not after search. Consumers trade off between search cost and information efficiency. The searchers acquire information about the quality and prices, while free riders update their believes by observing the adoption behavior of neighbors. In equilibrium, consumers' search strategy exhibits non-increasing threshold property: consumers with more neighbors are more likely to be free riders. I show that although there exist multiple equilibria, when search cost is small enough, there exists a unique interior BNE such that both searchers and free riders coexist in the market, and the prices are larger than marginal cost. I also investigate the impact of network structure on equilibrium outcomes. When the network is more connected, consumers engage in less search, the prices are higher, and the consumers' surplus is reduced
Nielson, Nathalie. "Vers un renouvellement de l'abus de position dominante face au défi de l'économie numérique ? Regards croisés entre droit antitrust américain et droit européen et interne de la concurrence". Electronic Thesis or Diss., Université Côte d'Azur, 2024. http://www.theses.fr/2024COAZ0036.
Texto completo da fonteThe digital economy has posed unprecedented challenges forcompetition law, as a combination of economic phenomena has led to a trendtowards market concentration, reducing their contestability. As gatekeepers, certainkey intermediation platforms have been able to adopt foreclosure strategies andpredatory behavior, raising virtually insurmountable barriers to entry. The ChicagoSchool’s economic approach, predominant since the 1980s in American law andgradually permeating European and French competition law, has thus shown itslimits, calling into question the effectiveness of competition law and specifically theprohibition of unilateral anti-competitive practices - monopolization or abuse ofdominance. Among other things, the fact that certain products or services are freeof charge, the strong relatedness of markets, and the difficulty of measuringsubstitutability have made the assessment of the relevant market and market powermore complex.Faced with digital market’s shortcomings, a regulatory reaction has been observed,with the adoption of the Digital Markets Act in European law and the introduction oflegislative proposals in the United States following the same model. Nevertheless,the diversity of intermediation platforms' business models makes sector-specificregulation difficult and imposes obligations that are sometimes too heavy for some,or irrelevant for others.European and domestic case law and practice have adapted to these issues,modernizing the notion of abuse to capture the unfair commercial practices of theseplatforms with renewed interest in abuse of exploitation and new theories ofexclusionary abuse. By contrast, US law has only recently taken up this issue, withthe introduction of multiple civil lawsuits against GAFAM since October 2020. Arenewal of prohibition is therefore necessary to consolidate this trend, and so thatcompetition law can once again effectively control private economic powers andmaintain free and fair competition, while preserving innovation
Karsenty, Adrien. "Les apports de l’économie industrielle à l’analyse concurrentielle des marchés de réseau et services numériques". Thesis, Paris 2, 2017. http://www.theses.fr/2017PA020066.
Texto completo da fonteThis PhD thesis set the milestones that are relevant for the competitive analysis of markets based on network activities and digital products or services. This work counts three parts, designed as separate essays, and aims to appreciate the impact of the characteristics of these markets on their competitive dynamics. The first part of the thesis tackles the concentration issue of online platforms. We specify a model of two-sided market in order to appreciate the different levels of interdependence on online platforms linking on firms (or advertisers) on one side and audience or consumers on the other side. As a result, network effects (synergies and scale economies relating to the number of users) are such that any competitive advantage (first-mover advantage, better quality or market share…), as low as it can be, turns out to be durable. The second part deals with the “relevant market” delineation in horizontal mergers issue and suggest an application to the retail market for fixed broadband Internet access. We econometrically analyze the demand for broadband access in order to verify whether or not there exists a segmentation (or even a differentiation) of the demand depending on the access technologies that can be very fast broadband or regular broadband access technologies. The third part examines the effects of “ad-blocking” software on the media and content providers whose business model is based on free access. We also specify a model of two-sided market in order to appreciate the role that Internet service providers can play to internalize network effects and to curb congestion phenomena
Thuillas, Olivier. "Les formes publiques de courtage informationnel : l’exemple des services géoCulture". Thesis, Sorbonne Paris Cité, 2017. http://www.theses.fr/2017USPCD016/document.
Texto completo da fontePublic access platforms to cultural content are today marginal in comparison to the global development of private access platforms. The model of informational brokerage enables us to observe and describe these platforms by analysing the central function of intermediation and its positioning with the actors upstream and downstream the platform itself. The analysis of geoCulture services makes it possible to qualify these public forms of information brokerage and to differentiate them from private platforms. Fulfilling public service missions, the platforms studied are characterized by a strong desire for cooperation between the actors and the editorialization of content. However, their development remains restrained by the pursuit of divergent, perhaps even contradictory, goals. More precisely, the objective of moderating acommunity of contributors prevails on the development of usages, where as the latter remains the ultimate priority of private platforms
Belletti, Chiara. "Empirical essays on information asymmetries on digital platforms". Electronic Thesis or Diss., Institut polytechnique de Paris, 2024. http://www.theses.fr/2024IPPAT017.
Texto completo da fonteThis thesis studies issues related to information asymmetry in digital markets. It aims at understanding the behavior of economic agents when standard reputation tools, such as ratings and reviews, may fall short.The first chapter investigates the impact of end-of-game concerns on the effectiveness of reputation systems as monitoring tools in digital markets. Using data from Airbnb, the chapter examines the effort decisions of hosts anticipating their exit due to non-compliance with a short-term rental regulation in the City of Los Angeles. With a Difference-in-Differences and Event Study approach, we compare how listing's effort-related ratings changed, compared to ratings on location, after the regulation announcement and during its implementation. The findings reveal a statistically significant decrease in effort-related ratings during the hosts' final periods, highlighting the limitations of reputation systems in addressing moral hazard within a finite game.The second and third chapters of this thesis study firm and worker behavior on a commercial crowd-working platform characterized by anonymity and limited employer-employee interactions.The second chapter provides descriptive insights into how crowd-working platforms are used for outsourcing AI-related tasks, particularly focusing on data training. The study begins by providing context on the platform under study and unveiling a recent growing demand for crowd-sourced data work. The chapter also examines how firms ensure tasks' execution quality through worker selection, wage setting, and monitoring. A regression framework allows for the identification of specific factors that distinguish demand for data work from other tasks. The higher targeting of demand towards predefined groups of contributors based on experience or geographic location, along with a larger rejection probability for data annotation tasks, underscores the importance of quality execution for firms outsourcing in this domain.The final chapter explores a Principal-Agent problem arising from monetary incentives, affecting the quality of the execution of data annotation tasks on crowd-sourced platforms. This problem cannot be adequately addressed with a reduced form approach. It stems from firms infrequently monitoring the quality of work, fostering moral hazard by the workers. A structural model assesses the equilibrium demand and supply of effort, revealing that metrics relying on observed task rejection underestimate quality. The study suggests a more accurate back-of-the-envelope correction based on a firm's own monitoring rate and simulates counterfactual incentive schemes. The simulation exercises reveal that a wage penalty for workers with rejected tasks could induce higher effort, increase platform revenue, require less monitoring, and enhance the potential of the platform. An alternative approach, although more costly for the platform, to encourage effort and reduce the likelihood of overlooking poor quality, implies providing subsidies for firms' monitoring efforts
Olave, cruz Isac Antonio. "L'intégration des plateformes de mobilité numérique dans les systèmes de transport multimodaux". Electronic Thesis or Diss., Université Paris sciences et lettres, 2024. http://www.theses.fr/2024UPSLD018.
Texto completo da fonteOver the past century, private cars have dominated the transport industry, profoundly shaping economic activity. However, this car-centric approach has also come with substantial costs, due to increasing traffic congestion and carbon emissions. In response, cities have increasingly adopted digital mobility platforms to improve transportation efficiency and enhance quality of life. Leveraging the principles of the sharing economy, digital mobility platforms provide short-term access to various means of transport. This model is appealing because it promotes more efficient use of capital and offers cleaner alternatives to individual car usage. To effectively address transport-related concerns, they must reduce car dependency, address travelers' dilemmas, and fostering complementarities with mass transit. However, the lack of robust empirical evidence limits our understanding of whether digital mobility platforms adhere to these principles. Therefore, the question of how to effectively integrate digital mobility platforms into existing transport systems remains an ongoing subject of scrutiny. This thesis contribute to this debate in four papers. Chapter 2 builds on the theory of platform economics to develop a business model typology for digital mobility platforms and identify the nature for public intervention. Chapter 3 explores the market dynamics between public transport and bike sharing, revealing complementarities after long periods of disruption in the network. Chapter 4 evaluates parking regulations for e-scooters. The findings suggest a positive effect on improper parking, but an unexpected negative effect on accessibility. Chapter 5 investigates car pooling's potential for carbon emission reduction, and explore policies to improve carbon mitigation. Overall, this thesis provides insights for decision makers and practitioners to design more efficient and sustainable multi-modal transport systems. Crafting regulations that guide technology toward economic and environmental objectives is paramount for the future
Šmilauer, Václav. "Cohesive Particle Model using the Discrete Element Method on the Yade Platform". Phd thesis, Université de Grenoble, 2010. http://tel.archives-ouvertes.fr/tel-00502402.
Texto completo da fonteMouhib, Mohamedyassine. "L'intermédiation : contribution à une théorie générale en droit du travail". Electronic Thesis or Diss., Bordeaux, 2024. http://www.theses.fr/2024BORD0455.
Texto completo da fonteThe development of digital platforms in the mid-2000s was accompanied by an intense legal debate seeking to determine the nature of the activity carried out by these new economic players. They claim to be no more than intermediaries. But what does this mean from the point of view of employment law ? This study seeks to answer this question by proposing a theory that is intended to be general, capable of resituating the activity of digital platforms among the other traditional forms of intermediation that are already familiar to labour law. Faced with the growing development of new intermediation techniques, from portage salarial to CDI intérimaire, from prêt de main-d’oeuvre auprès d’une jeune, petite ou moyenne entreprise to digital platforms, this theory seeks to reveal the underlying coherence of phenomena that may appear at first glance to respond to distinct logics. By proposing an overall representation, the construction of such a theory provides an opportunity to identify a fundamental property of any intermediation scheme : multipolarity. This simply means that these contractual arrangements mobilise a plurality of protagonists. However, the multipolarity of intermediation schemes is addressed in very different ways by employment law. The framework for applying the legal rules that govern these forms of work may be bilateral or multilateral. In the latter case, by emancipating itself from the traditional figure of the employer, labour law takes into account a plurality of mutually independent actors when applying a legal rule to a work situation. Thus, while offering an overall representation of the different forms of intermediation, this study aims to reveal the diversity of ways in which labour law is applied
Ngo, Dinh Thanh. "Runtime mapping of dynamic dataflow applications on heterogeneous multiprocessor platforms". Thesis, Lorient, 2015. http://www.theses.fr/2015LORIS371/document.
Texto completo da fonteModern multimedia applications are subject to an increasing complexity with widespread standards. This has led to the interest in dataflow approach that offers a powerful perspective on parallel com- putations at high level. In the meantime, the emergence of massively parallel architectures has revealed the trend towards heterogeneous Multi-Processor System-on-Chips (MPSoCs) to offer a better perfor- mance and energy tradeoff than their homogeneous counterparts. However, this also imposes challenges to the mapping of multimedia applications on such complex architectures. This thesis presents an adaptive methodology for mapping dataflow applications on heterogeneous MPSoCs. This thesis focuses on video decoders specified in RVC-CAL language, a dedicated dataflow language for video applications. Existing static approaches cannot capture all behaviors in dynamic dataflow applications. Thus, this requires to adapt the mapping according to the input data. The algorithm offers some adaptive parameters combined with our analyt- ical communication model to improve a performance while consider- ing load balancing. We evaluate our algorithms on a set of randomly generated benchmarks and real video decoders like MPEG4-SP and HEVC. Experimental results reveal that our mapping methodology is fast enough (in milliseconds) and the runtime remapping signifi- cantly improves the initial mapping. In the remapping process, we take the migration cost into account because the reconfiguration time also contributes to the overall performance
Trifan, Laurentiu. "Résilience dans les Systèmes de Workflow Distribués pour les Applications d’Optimisation Numérique : Conception et Expériences". Thesis, Grenoble, 2013. http://www.theses.fr/2013GRENM044.
Texto completo da fonteThis thesis aims conceiving an environment for high performance computing in a numerical optimization context. The tools for conception and optimization are distributed across several teams, both academics and industrial, which collaborate inside a unique project. The tools should be federated within a common environment to facilitate access to researchers and engineers. The environment that we offer, in order to meet the above conditions, consists of a workflow system and a distributed computing system. The first system aims to facilitate the application design task while the latter is responsible for executing on distributed computing resources. Of course, communication services between the two systems must be developed. The computation must be performed effectively, taking into account the internal parallelism of some software code, synchronous or asynchronous task execution, the transfer of data and hardware and software resources available (e.g. load balancing). In addition, the environment should provide a good level of fault tolerance and software failures, to minimize their influence on the final result or the computation time. An important condition in particular is to implement recovery devices on error occurence, so that the extra time for error handling remains well below the total time of re-execution. As part of this work, our choice fell on the Yawl workflow engine, which has good characteristics in terms of i) hardware and software independence (client-server system that can run on heterogeneous hardware) and ii) error recovery mechanism. For distributed computing part, our experiments were performed on the Grid5000 platform, using up to 64 different machines on five geographical sites. This document details the design of this environment and the extensions and changes we have had to perform on Yawl to enable it to run on a distributed platform
Ahmat, Al Saïd. "Actions et réactions stratégiques des firmes installées face à l’arrivée de plateformes numériques, le cas des écosystèmes d’affaires mobil banking et banques au Tchad". Electronic Thesis or Diss., Reims, 2023. http://www.theses.fr/2023REIME004.
Texto completo da fonteThe objective of the thesis is to draw up recent theoretical contributions on strategic actions and reactions around business ecosystems and partly underpin our research problematic since we are focusing on a new organizational field carried by digital platforms. The particularity of these platforms is characterized by an organizational model based on a cooperative system or on a traditional capitalist system, driven by the search for profit. This research is part of the field of strategy and consists of studying the games of actors, relying more specifically on business ecosystems (abbreviated to ESA), a concept that appeared in the work of Moore (1993, p.76) and is defined as a set of "actors maintaining relationships of coopetition" (Koenig, 2012, p. 210). ESA refers to an economic community of organizations that interact with each other to produce goods and/or services that can create value for customers and for themselves. The ESAs we are studying are grouped around platforms called mobile banking (new entrants) and banking institutions (established firms). The problem that led to our thesis is to understand how the platforms have imposed themselves, by what strategic actions they have managed to make a place for themselves on the market and eventually dominate it. Our research field is Chad and our methodology is based on a qualitative analysis of a case study. The data collected will allow us to retrace the history of events and to study the discourses of the actors involved in the process at work by means of a manual analysis of the corpus. The proposals produced can shed new lighting on the strategic actions of the actors
Lemaire, Vincent. "Le droit public numérique à travers ses concepts : émergence et transformation d'une terminologie juridique". Thesis, Paris 1, 2019. http://www.theses.fr/2019PA01D027.
Texto completo da fonteThis work is about the reconstruction of the public law because of digital new uses, reviewing the transformation of the main public law concepts. This in order to identify which concepts can withstand, change or disappear because digital new uses. This will be the moment to mention the new digital items, to confront their compatibility by the public law. Moreover, we will consider how the public law is able to comprehend news uses and digital reticulated communication structures. Then, the purpose of this work is to reintegrate public law into the network paradigm in order to find out the ability for the public government to take part efficiently in most digital activities and digital business activities. In this way, we will be able to design how to guide the conceptual transformation of the public law in the digital transition of the government facing new digital challenges
Abou, Chaz Nisrine. "Etudes expérimentale et numérique des plateformes granulaires renforcées par géosynthétiques sur sol mou". Electronic Thesis or Diss., Université Grenoble Alpes, 2024. http://www.theses.fr/2024GRALI031.
Texto completo da fontePoor subgrade quality is a pervasive challenge in the construction of unpaved roads. Geosynthetics (GSYs) have emerged as innovative solutions since their initial usage in the late 1970s. Depending on the type of GSY employed, they can fulfil one or several roles, including separation, reinforcement by tensioned membrane effects, and stabilization by interlocking and/or friction at the soil-GSY interface. Few design methods exist in the literature to quantify these mechanisms, but they have limitations due to their calibration on specific GSY and soil parameters and, at times, under static rather than cyclic loading conditions. The various factors and parameters that influence the dominant mechanism and its corresponding contribution to platform enhancement underscore the necessity for further exploration in this area.To address this persistent issue, a series of experimental and numerical studies were conducted. The experimental part studied the performance of reinforcement under cyclic vertical and traffic loadings using two woven geotextiles (GTXs) with two different tensile stiffness and two base course thicknesses. Additionally, alongside the experimentation, a numerical model coupling the discrete element method and the finite element method (using Software-Defined Edge Computing) was employed. This model aimed to showcase the impact of GSY and soil parameters on reinforcement performance and provide insights into aspects challenging to measure through experimentation.The tested unpaved road sections are composed of a subgrade layer with a CBR around 1% covered by a compacted base course layer with thickness of 300 mm or 500 mm. The GTXs are placed at the interface between the subgrade and the base course layers. The results showed that the 500 mm base course reinforced platform did not exhibit reinforcement effects under vertical cyclic loading. However, the use of a 300 mm base course with GTX significantly reduced settlement compared to an unreinforced base course of the same thickness (300 mm) and to the thicker base course (500 mm). The most important improvement was observed with the highest-stiffness GTX. Moreover, three tests were performed under traffic loading applying by the Simulator Accelerator of Traffic (SAT). It was shown that traffic loading exerted greater deformation in the base course layer compared to vertical loading, but definitive conclusion can hardly be reached about the comparison between reinforced and unreinforced platform.In the numerical model, a behavioural law (1D) was integrated, considering the variation of the soil reaction modulus during loading and unloading phases and with cycles, and describing the transition of the soil from plastic to quasi-elastic behavior. In addition, the purely frictional base course layer revealed its incapacity to sustain the loading applied in the experimental. This inherent limitation prompted the incorporation of adhesion between soil particles to rectify this shortcoming in load-bearing capacity. Once calibrated the numerical model proved capable of accurately replicating the behavior of GTX-reinforced platforms in the first cycle and with cycles. It facilitated a quantification of the GTX friction effort and GTX tension effort with cycles. Initially, frictional forces outweighed the tensioned membrane effect, but as deflection increased with cycles, the latter became more prominent. This dynamic highlighted a diminishing dominance of the soil confinement mechanism with cycles, giving way to the increasing significance of the membrane effect. Furthermore, the subgrade softness, the GTX rigidity, the mattress-GTX interface parameters and the base course mechanical parameters influenced the behavior of the model
Tendil, Anthony. "Contrôles tectoniques, climatiques et paléogéographiques sur l'architecture stratigraphique de la plateforme carbonatée urgonienne provençale (France) : approches sédimentologiques, géochimiques et numériques intégrées". Thesis, Aix-Marseille, 2018. http://www.theses.fr/2018AIXM0230.
Texto completo da fonteThe analysis of carbonate systems is at the heart of major economic and societal challenges, especially in the energy field since they represent significant oil and gas reserves. The present thesis focuses on the Urgonian Provence platform (upper Barremian–lower Aptian interval) which is considered as a valid outcrop analogue of middle East carbonate reservoirs. About thirty stratigraphic sections, including newly acquired cores, are considered throughout the Provence domain. The recognition of biostratigraphically constrained exposure and drowning surfaces enables us to restore the regional palaeogeographic evolution along with the stratigraphic architecture. Several phases of platform progradation toward the adjacent basins, interrupted by episodes of changes in carbonate production, are identified in Provence. A comparable stratigraphic scenario is proposed for the peri-Vocontian Urgonian platforms. In Provence, the reservoir compartmentalisation of the Urgonian platform is mainly controlled by the sequence stratigraphic context that induced a distinction between early cemented carbonates and those preserving part of their original porosity. The geological rules provided in this study 1) are implemented into a 3-D numerical model intended for fluid-flow simulations at the scale of the Fontaine-de-Vaucluse karstic aquifer, whose karst spring is the fifth largest in the world, and 2) help in predicting the sedimentary and petrophysical heterogeneities of carbonate systems
Cazaubiel, Arthur. "Essais sur l'économie des plateformes". Electronic Thesis or Diss., Institut polytechnique de Paris, 2020. http://www.theses.fr/2020IPPAG005.
Texto completo da fonteThis dissertation deals with the economics of platforms through three independent chapters. The first one develops a theoretical model around exclusive sales, or flash sales. This practice, very common on the Internet, consists in offering consumers an offer to take today, with no opportunity to benefit tomorrow. The second chapter evaluates the substitutability of hotel room distribution channels in Scandinavia, particularly between the hotel’s website, Booking, and Expedia. We also analyze the decision of a hotel chain to boycott a sales channel. Finally, the third chapter analyses the implementation of a new strategy by Booking with its suppliers
Bailly, Adrien. "De la consommation collaborative à l’économie de plateformes : étude des transactions entre particuliers dans l’espace socio-numérique". Thesis, Université de Lorraine, 2019. http://www.theses.fr/2019LORR0220.
Texto completo da fonteThe last decade has been marked by the emergence of numerous economic models associated with the notion of collaborative consumption. These consumption contexts need consumers to conduct new activities. This research aims to provide a theoretical understanding of these emerging practices. The notion of collaborative consumption itself is an important part of the phenomenon that we try to understand but doesn’t help us to circumscribe the object of this research. Indeed, the definitions proposed by researchers and by consumers do not allow to identify the specificity of collaborative practices. In this context, we choose to define the research object from a spatial point of view. The massive diffusion of digital technologies makes it possible to link spaces which were previously separate. It allows to carry out transactions that mix elements which traditionally belonged to the economic sphere or to the domestic sphere. This research is therefore limited to these transactions initiated online, i.e. those specific to a platform economy. A theory of science inspired by the pragmatist tradition and a mainly ethnographic methodological apparatus were used to study these transactions. Our study of the website www.leboncoin.fr allows us to identify how this platform fosters the acquisition of market skills without managing to solve the social exclusion inherent to this intermediation model. Our study of private renting initiated online allows us to explore the relationships between users and platforms induced by a more bureaucratic intermediation model. We also show the professionalization of practices. This work allows us to conclude that collaborative consumption is above all a set of narratives that accompany and legitimize platform capitalism and that intermediation relationships cannot be understood without taking into account the way in which consumers perform them and try to transform them
Barbe, Anne-Sophie. "De l’évaluation par les utilisateurs à l’évaluation ouverte : pouvoirs, valeurs et mesures à l'épreuve du capitalisme de plateformes". Thesis, Lyon, 2020. http://www.theses.fr/2020LYSE3025.
Texto completo da fonteThis PhD dissertation focuses on the (re)articulation of powers and values when digital platforms open evaluation to their users. While the construct of digital platforms refers to heterogeneous phenomena (chapter 1) digital platforms are generally considered as new organizational forms. Focusing on transaction platforms, we question the foundations of this assumption and show that management scholars retain users’ evaluations as one of its core components (chapter 2). We therefore conceptualize users’ evaluation as open evaluation - i.e. an evaluation without any pre-defined criteria - to enrich the problematization of its political issues (chapter 3). In fact, if Foucauldian studies approach the development of evaluation tools as a broad historical dynamic, more restrictive conceptualizations of power outline the concrete practices through which actors exert power through evaluation tools and insist more specifically on the role of the definition of the evaluation criteria. But how does power serve value when it imposes no common measure of it? Using case studies - conducted at the level of a market populated by platforms (chapter 4) and at the level of a platform (chapter 5) - we show that while platform managers do not define the evaluation criteria to prevail in the evaluations their users perform, they exercise power and insert values in the exchanges that they intermediate by sketching the landscape of the evaluations produced by the users. To do so, they define the commensurative perimeter of these evaluations and specify the relations that unite the stakeholders of the latter
Michalon, Barthélémy. "Framing, shaping, and maneuvering : exercising power in building online content regulation". Electronic Thesis or Diss., Paris, Institut d'études politiques, 2024. http://www.theses.fr/2024IEPP0019.
Texto completo da fonteI used qualitative data analysis and the multiple case study method to understand how political, platform, and civil actors exercise power in building regulatory frameworks, and thus a governance system, for online content moderation. I analyzed the exercise of power through three case studies, each on a different form of regulation: the Code of conduct on countering illegal hate speech online (co-regulation), Meta’s Oversight Board (self-regulation) and the Digital Services Act (statutory regulation).These cases served to develop an analytical framework (the FSM model) and to successfully test its replicability. It is based on the idea that actors exercise power at different stages of a regulation’s policy process in at least one of three ways. Framing involves influencing perceptions about the regulation and the actors involved. Shaping consists of impacting the regulation’s content. Finally, maneuvering refers to affecting its practice, mostly during the implementation phase. The comprehensive analysis of power dynamics across three regulatory settings allowed me to highlight controlled delegation as a central feature in the governance of online content. Empirical evidence points to a pattern: the actor behind each regulatory initiative – be it a public authority or platform company – shaped the regulatory framework to actively engage other actors in content moderation, while ensuring that this delegation operated within the boundaries it had defined. My approach, grounded in the exercise of power, yielded insights into how delegating actors balanced empowering other agents with establishing boundaries and oversight mechanisms to retain control over their operations
Parmentier, Stéphanie. "Du compte d'auteur à l'auto-édition numérique : études des formes et des pratiques de l'édition non sélective". Thesis, Bordeaux 3, 2020. http://www.theses.fr/2020BOR30020.
Texto completo da fonteInternet allows authors to publish in a few clicks without passing through the necessary phase of the Publishing House, as it has been the case so far. Previously authors had no alternative but publishing at their own expense, most of the time quite expensive. Thanks to the net, they benefit today from various spaces: Kindle Direct Publishing (KDP), Amazon, is an auto-edition platform that encounters a phenomenal success ; KDP has reshuffled the norm bringing into light totally unknown writers, with no real writing experience nor particular ambition, and made them visible on the net, opening doors of a world that was kept accessible to a few lucky ones before. Our study aims at better understanding the phenomenon of alternative edition that is coming up to force, and to understand who exactly these authors investing in KDP are, their motivations and their publications. More broadly, we aim at demonstrating that these new forms of publications offer different literature, equally entertaining, certainly cheaper, not always present in libraries but easily accessible online
Alimam, Mayla. "The place of enterprise social media platforms in today’s enterprises : evaluation of usage and impact on workplace tools". Electronic Thesis or Diss., Evry, Institut national des télécommunications, 2017. http://www.theses.fr/2017TELE0007.
Texto completo da fonteToday’s organizations are increasingly promoting a shift of employees’ ways of working towards more agility and flexibility. This shift is empowered by new IT tools commonly known as “Enterprise Social Media” (ESM). Taking mainly the form of integrated platforms, these tools are deployed with the promise of enhancing employees’ communicative activities at the workplace while capitalizing on their social connections. Yet, it remains unclear for companies how their employees benefit from the use of these new tools (i.e., ESM platforms). Managers are unable to evaluate the use of these platforms and thus, tangibly measure the success of their investments. Moreover, introducing ESM platforms to the workplace impact the way the existing tools, such as email, are regarded and used. This leads to the question of whether these new platforms may be substitutes for the use of the existing tools. This thesis tackles the mentioned polemical questions about the place of ESM platforms in today’s enterprises. Carried out jointly with Orange labs, the thesis assesses the role ESM platforms could play in supporting organizations in reaching their objectives and hence sustaining their businesses in an extreme competitive context. It explores the real use of these platforms by offering a quantitative social network analysis and data mining of an established ESM platform currently in use. While relying on a proposed research model that characterizes the activity, the applied hypothesis tests allow determining the correct use of ESM platforms, which in turn indicates the success of their deployments. Moreover, the thesis argues through a reasoning approach that the ESM platforms are not capable of substituting the use of existing workplace tools. Instead, they work in tandem with certain tools such as email. Based on the latter argument, the email tagging service is introduced as an example of how existing workplace tools may be enriched with social features to derive increased benefit for the workforce. The thesis finally validates the service through implementation and testing. To conclude, it proposes and discusses scenarios of future social systems that involve the overall set of workplace tools in enterprises
Le, Bellu Sophie. "Capitalisation des savoir-faire et des gestes professionnels dans le milieu industriel : mise en place d’une aide numérique au compagnonnage métier dans le secteur de l’énergie". Thesis, Bordeaux 2, 2011. http://www.theses.fr/2011BOR21825/document.
Texto completo da fonteIn large industrial companies, the transmission of the embodied in professional practices traditionally takes place as part of a series of training courses given by former operators and of journeyman practices implemented directly on site. This situation will undoubtedly change, because nowadays many companies are facing the problem of a massive departure of operators into retirement. This requires, on the one hand, the preservation of the appropriate professional gestures for the maintenance of aging technical plant, and on the other hand an adaptation of the professional gestures to technological evolution. In the energy sector, Electricité de France (EDF) is also confronted with this issue of the evolution of these journeyman practices. For the company, the situation is rendered more complex as a result of highly variable practices due to the presence of almost one hundred power generation plants with a wide geographic distribution, and with diversified generation methods involving different cultural practices (nuclear, thermal, hydraulic).The present research addresses two objectives:(1) On the theoretical level, we sought to understand, based on field data, the nature of the explicit and implicit transmission and formalization of knowledge underlying the performance of professional gestures. This takes place: - on the one hand, by means of the confrontation of the existing approaches in the different schools, at international level, with the empirical reality; - and, on the other hand, by means of the identification of the gap in the literature as concerns the treatment and modelling of tacit knowledge and embodied know-how as compared to the practical requirements of transmission.(2) On the practical level, we sought to develop an approach to situational learning of embodied know-how by exploring the recourse to digital ethnography tools. This aims:- on the one hand, to perpetuate the knowledge linked to the gestures;- and, on the other hand, to devise a method for the creation of structured, video-based educational supports. This practical phase has afforded the opportunity to test our models on real life cases. The combination of technical, theoretical and methodological tools we applied has led to the design of several products.We designed, and tested on the field, a method for the capture and analysis of professional gestures. This method is based on dual video recordings: an external camera and a subjective camera mounted on the safety helmet of the operator performing the gesture. This recording is coupled to a specific protocol of oral expression whilst performing the gesture.We also modelled, tested and formalised a teaching resource in an educational setting: the Multimedia platform for APprenticeship (MAP). It is based on a decomposition and structuring of the gesture illustrated primarily by annotated video but also by means of functional schematics images, photos, etc. This decomposition results from the analysis of the gesture carried out upstream and based on Russian Activity Theory and Perceived Quality.These two products provide an operational chain intended for the trainers of EDF’s Training Division, for the capture and transmission of the tacit and explicit knowledge involved in professional gestures. The incorporation of the MAP into EDF’s educational system, in real life training sessions, has been very positively evaluated and received by both trainers and trainees. In May 2011 it was decided to launch the industrialization phase of the method and the MAP throughout the company
Heuguet, Guillaume. "Métamorphoses de la musique et capitalisme médiatique. Au prisme de YouTube (2005-2018)". Thesis, Sorbonne université, 2018. http://www.theses.fr/2018SORUL153.
Texto completo da fonteWhile music digitization has become a major theme of public discourse and academic research, YouTube, a video publication website founded by three ex-employees of PayPal and now the property of Google, is today recognized as the first media used for music listening in France. Through an analysis of digital archives of the Web and the compilation of media sources, this thesis analyzes what a company coming from technology « does » to musical culture, taking into account the regular change of its forms and its promises. A first chapter deals with the effects of power and blurriness in the mediatization of YouTube and its relationship to music. A second chapter analyzes the way music shaped YouTube, proposing a genealogy of relationships between music and media apparatus, linking the invention of recorded music, the standardization of online listening software and the « musicalization » of YouTube. A third chapter discusses music as an opportunity. We identify how the company invested in music as a key strategic ressource, while shaping the practice of music gathering and publication around values of popularity and creativity. A fourth chapter concerns the construction of a market for music built upon the technological and juridical control of the works versions and the financing by advertising, interrogating the limits of this model. We conclude by showing the intricacy of discourse about the transformation of musical culture with the logics of permanent change from the actors of media capitalism. From this point, we defend the necessity of studying the micropolitics of formats
Raynal-Astier, Corinne. "Réflexions autour de l’intégration du numérique dans les formations universitaires de Français Langue étrangère ou de didactique du Français Langue Étrangère. Des usages et des normes". Thesis, La Réunion, 2019. http://www.theses.fr/2019LARE0026.
Texto completo da fonteThis doctoral research examines the learning pathways of students enrolled in two online dis-tance learning programmes of the University of Tours (France) and the University of Cape Town (South Africa) departments of Didactics of French as a Foreign Language (FFL). While learning platforms are regularly studied from an interactionist, cognitivist or socioconstructiv-ist perspective together with questions relating to the learning process and ways to improve the latter, they are rarely considered as spaces imposing a certain vision of higher education. However, they propose a structured architecture in order to favour certain aspects considered important in the teaching-learning process. Seen as metaphors of political or scientific texts, they can be read as an institutional, scientific and didactic project that learners must adopt. In this research and through a reading of Michel de Certeau’s work, we analyse student learning pathways, from the expected or even imposed use of platforms to alternative usage. We ques-tion the reasons for their online presence or absence, highlighting, on the one hand, their dis-cursive contradictions, with which they comply in order to meet the expected platform usage or to be heard, read, recognised by the institution and, on the other hand, their off-platform "learning elsewhere" persona. Some form of online teaching and learning “standard” emerges from their negotiation between what is "imposed" and what the alternative, “re-directed” us-age. This “standard” resembles another one: the language standard. This study has made it clear that the LMS (Learning Management System) architecture reproduces the system to which it belongs thereby prescribing learner homogeneity and consequently side-lining diversi-ty. This study, which is qualitative hermeneutical in nature, was made possible thanks to in-depth interviews with French and international students enrolled in the above-mentioned distance education programmes, ethnographic notes, participant observations and analysis of online interactions. It also draws on discourse analysis to question political and scientific texts
Nguyen, Thi Minh Tuyen. "Taking architecture and compiler into account in formal proofs of numerical programs". Phd thesis, Université Paris Sud - Paris XI, 2012. http://tel.archives-ouvertes.fr/tel-00710193.
Texto completo da fonteLe, Roy Marylou. "La loyauté des plateformes à l'égard des consommateurs". Electronic Thesis or Diss., université Paris-Saclay, 2021. https://buadistant.univ-angers.fr/login?url=https://bibliotheque.lefebvre-dalloz.fr/secure/isbn/9782247226597.
Texto completo da fontePlatforms are online intermediation services of the information society. These operators cover a wide range of players such as marketplaces, search engines, social networks and operating systems. Several European and national texts have contributed to the emergence of the category of platforms, and a distinction between platforms, very large platforms and gatekeepers is now emerging in the Digital Services Act package. The development of platforms poses challenges to all branches of law, particularly in the areas of consumer law, competition law, personal data law and fundamental rights. The study focuses on the relationship between platforms and consumers, as they are one of the sides of their market. This analysis from the point of view of fairness is justified since the obligation of fairness on the part of platform operators was initially introduced into French consumer law.The study starts from the observation that the current system is inadequate, since the fairness of platforms with regard to consumers has been only partially addressed. It is true that platform loyalty from the point of view of contract makes it possible to regulate, in part, the unbalanced relationship between platforms and consumers. However, the fairness of platforms is incomplete beyond the contract. Indeed, the manipulation of consumers is insufficiently taken into account by the law, while taking into account their welfare in competition law is complex.This is why the study sets out to propose a new system of platform fairness in the interest of consumers. A broad conception of platform fairness is adopted as a guiding principle to secure digital services in good faith and in the interest of consumers. This should be complemented by the imposition of new practices for platforms to respect and by the establishment of new "rights to" for consumers. The study also envisages the implementation and effectiveness of platform fairness, on the one hand, through compliance mechanisms imposed on platforms, and on the other hand, through the introduction of control and sanction instruments
Alimam, Mayla. "The place of enterprise social media platforms in today’s enterprises : evaluation of usage and impact on workplace tools". Thesis, Evry, Institut national des télécommunications, 2017. http://www.theses.fr/2017TELE0007/document.
Texto completo da fonteToday’s organizations are increasingly promoting a shift of employees’ ways of working towards more agility and flexibility. This shift is empowered by new IT tools commonly known as “Enterprise Social Media” (ESM). Taking mainly the form of integrated platforms, these tools are deployed with the promise of enhancing employees’ communicative activities at the workplace while capitalizing on their social connections. Yet, it remains unclear for companies how their employees benefit from the use of these new tools (i.e., ESM platforms). Managers are unable to evaluate the use of these platforms and thus, tangibly measure the success of their investments. Moreover, introducing ESM platforms to the workplace impact the way the existing tools, such as email, are regarded and used. This leads to the question of whether these new platforms may be substitutes for the use of the existing tools. This thesis tackles the mentioned polemical questions about the place of ESM platforms in today’s enterprises. Carried out jointly with Orange labs, the thesis assesses the role ESM platforms could play in supporting organizations in reaching their objectives and hence sustaining their businesses in an extreme competitive context. It explores the real use of these platforms by offering a quantitative social network analysis and data mining of an established ESM platform currently in use. While relying on a proposed research model that characterizes the activity, the applied hypothesis tests allow determining the correct use of ESM platforms, which in turn indicates the success of their deployments. Moreover, the thesis argues through a reasoning approach that the ESM platforms are not capable of substituting the use of existing workplace tools. Instead, they work in tandem with certain tools such as email. Based on the latter argument, the email tagging service is introduced as an example of how existing workplace tools may be enriched with social features to derive increased benefit for the workforce. The thesis finally validates the service through implementation and testing. To conclude, it proposes and discusses scenarios of future social systems that involve the overall set of workplace tools in enterprises
Jönsson, Madeleine. "Political economics of gender relations in information and communication technologies in agricultural development. The case of knowledge-based platforms for farmers in Kenya". Thesis, Université Paris-Saclay (ComUE), 2018. http://www.theses.fr/2018SACLA018/document.
Texto completo da fonteLow-income sub-Saharan African countries are confronted with demographic explosion since the last 60 years. Consequently, agriculture plays a key role in ensuring food security. The agricultural sector is also the main source of employment in this region. Women are the major contributing labour force in agriculture in these sub-Saharan African countries. Connected to their key role in the agricultural sector, women farmers are prioritised in policy intervention. Moreover, agricultural extension services are necessary to adapt to different constraints in these countries. Transfer of knowledge is also required to guarantee farm yields and consequently improve small-scale farmers’ livelihoods. Lately, information and communication technologies (ICTs) have enabled the development of new tools, aimed at improving the scope and the effectiveness of advisory services. Policy makers in sub-Saharan African countries are nonetheless confronted with critical questions regarding the impact of these tools, which can also contribute to a ‘digital gender gap’. These issues particularly concern women farmers.This PhD research analyses how ICT tools take into account gender relations, and the situation of women farmers. The thesis is based on the case of Kenya. The dissertation particularly focuses on the development of knowledge-based platforms in agriculture, an ICT policy instrument used by the Kenyan Government to achieve public policy objectives. This country is emblematic because it believes in the assumption that platforms can be inclusive of women farmers’. To answer to this research question, the work is based on three different institutional economic research approaches: feminist economics, the French regulation theory, and economics of services. A conceptual and methodological framework is presented to analyse the inclusion of gender equality in knowledge-based platforms at macro-, meso-, and micro- level.The results provide evidence that gender equality objectives is a fundamental guiding principle to the Government of Kenya. The analysis show that platforms are considered as new tools of inclusiveness in farm advisory services innovation. Observations from a developed platform typology framework show however that platforms can be source of gender inequality. It especially concerns women farmers unequal access to these instruments and the standardised services that they offer. This is essentially related to the institutional nature of the platform. Indeed, as it turns out, a high number of these instruments are based upon complex partnerships, and financed by multi-national corporations and/or foundations from the agrifood industry based in the Northern hemisphere. Combining institutional economic approaches allowed to bring out critical points of inclusion to be considered by policy makers and platform developers. Disregarding these specificities may make these platforms into new vectors of exclusion. Recognising and taking into account the conditions for inclusion can bring to light powerful levers for improving the efficiency of platforms
Jouan, Marine. "La construction sociale du marché du financement participatif en France". Electronic Thesis or Diss., Paris, ENST, 2017. http://www.theses.fr/2017ENST0052.
Texto completo da fonteSince the end of the 2000s, crowdfunding platforms have been developing in France with the promise of a direct and disintermediated relationship between project owners and funders, facilitating access to funds for project owners and allowing French Internet users to fund projects of their choice. This PhD dissertation studies this phenomenon by combining ethnographic observation and interviews with various actors who have participated in the development of this activity. The research shows that the institutionalization of crowdfunding in France stems from a collective action involving industry professionals, representatives of public authorities, platform partners, and the media. While platforms defend a model of self-organization and autonomy, it appears that their development would not have been possible without the intervention of public authorities, who have created a favorable legal framework to crowdfunding, in order to change the relationship of the French population with its savings and to encourage the contribution to the economic health of new firms in a context of crisis. The study also shows that, despite the extreme heterogeneity of the three majority crowdfunding models studied (reward-based, lending-based, and equity-based), there is a collective effort to highlight common characteristics and to blur the heterogeneity of the sectors (on the one hand the world of cultural creation, on the other the world of finance). Platforms, as socio-technical devices, seek to present themselves as neutral instruments that favor a natural match between fund seekers and funders. This research shows that actually the growth of this financing model is the result of a market labor carried out by professionals in the sector to bring two types of users on their platform: the fund-seekers on one side and the funders on the other. The research also shows that the platforms strategic decisions try to balance out quantity and quality of projects. To reduce risks, platforms put in place qualification and project selection processes, often imported from traditional finance - contradicting the idea of democratization of access to funding. In their development efforts, they also seek to build relationships with traditional players from the world of finance. In doing so, they reintroduce new intermediaries that complicate the relationship between fund-seekers and funders
Bouchaud, Paul. "Beyond the Black Box : social structures and dynamics in the digital age : reconstructing, modelling and assessing the impact of major digital infrastructures". Electronic Thesis or Diss., Paris, EHESS, 2024. http://www.theses.fr/2024EHES0162.
Texto completo da fonteThis thesis examines the effects of algorithmic systems used by major online platforms on public discourse and society. Through experimental audits and social simulations, the research aims to decipher how these systems, which serve billions of users, operate. The thesis addresses three main objectives: conducting audits of online platform algorithmic systems, investigating mitigation measures for misalignments between platform operations and public good, and enhancing social media simulations with massive field data. Notable contributions include a comprehensive study of Meta's Ad Library, an analysis of Amazon's and Twitter's recommendation systems, and the creation of a data donation tool to gather information on actual user experiences across platforms like Facebook, Google Search, YouTube, and Twitter.The thesis also considers the methods used in algorithmic auditing, emphasizing the need to account for personalization and individual user traits when evaluating these systems. A simulation of a Twitter-like platform was developed, combining predictive models of user engagement with large-scale data collection. This approach was used to assess how content ranking strategies focused on maximizing engagement affect the information users see, showing reduced content variety and altered political representation. The research concludes by investigating alternative content curation approaches beyond immediate user engagement, including a ranking system based on diverse user approval, while recognizing the difficulties in assessing the "democratic value" of civic content to create viable alternatives to current engagement-based systems
Lampert, Arthur. "L’autonomie du travailleur". Thesis, Paris 2, 2019. http://www.theses.fr/2019PA020079.
Texto completo da fonteThe economy’s “tertiarisation” and the development of new information and communication technologies are part of the evolution of the working relationships. Several schemes issued by professional practice and endorsed by the law (fixed annual working time, home office, “umbrella companies”) make it possible to set up a new working relationship that differs from the traditional link of legal subordination, key of the “salariat”. At the same time, there is an expansion of self-employment for which digital platforms are competing. Paradoxically, the expansion of the employee’s autonomy comes with a decline of the autonomy of the self-employed. The convergence between these two schemes of working organization imposes to narrow the gap between the rules governing them. Thus, the decrease of the employer’s sphere of authority must be linked with a lightering of its obligations. At the same time, the benefit of certain protective measures which was reserved to employees should be extended to the self-employed since their situation has evolved. As a whole, it leads to an evolution of the labor relationships which could finally look like a revolution
Baytok, Hazal. "Participation in Citizen Science : Motivational and Contextual Factors". Electronic Thesis or Diss., université Paris-Saclay, 2024. http://www.theses.fr/2024UPASI001.
Texto completo da fonteCitizen science is the participation of people who are not scientists in research processes such as data collection and analysis. Citizen science provides various benefits like faster and easier data collection, investigation of environmental challenges from biodiversity to climate change, as well as contributing to astronomy research and leading to collaboration between the scientists and the public.Realising the potential benefits of citizen science depends on understanding the perspectives of participants. In this study, I examine different ways of participation in citizen science and how the motivations of participants, the design of the platforms, and other factors are associated with these. The thesis contributes to our understanding of the key ingredients in designing citizen science programs so as to increase the engagement of the public.In the first part, I carried out a literature survey by bibliometric analysis. This part focuses on challenges, success factors, and motivations in citizen science. The rest of the thesis is composed of one qualitative and another quantitative study by focusing on three citizen science platforms that are actively used in the field of ornithology in two countries, Turkey and France, which are Faune-France from France, Trakuş and eKuşbank (eBird Turkey) from Turkey.In the qualitative part, through semi-structured in-depth interviews, I examine the actors, different ways of participation, motivations, and negative externalities that may arise using the Multi-Sided Platforms (MSPs) and knowledge commons literature.The results of this part helped us identify four roles in the platforms: birdwatcher, bird photographer, scientist, and hunter, interacting with each other and creating externalities.I also found two types of participation: active and passive. Regarding motivations, the findings suggested similarities in the previous studies. However, as different from previous work, I highlighted the need to distinguish motivations for engagement in the platform on the one hand and motivations for the subject matter (birds in our case) on the other.In the second part, by conducting a large-scale survey targeted at the participants of the three platforms and an econometric analysis, I examined how motivations are associated with participation, as well as the negative externalities and values created by the platform. In this part, I draw upon the Self-Determination Theory (SDT), Multi-Sided Platforms (MSPs), and negative externalities concept from the commons literature.The findings in the second part suggest that the two types of motivations identified in the first part (motivation for the subject and motivation for platform engagement) are positively associated with active and passive participation. Also, values offered by the platform and platforms' ways of addressing negative externalities have different impacts on active and passive participation based on the context, such as the participants' perceived importance of competitions positively affecting their active participation in France, whereas not having a significant impact in Turkey. Similarly, participants' perceived importance of the protection of sensitive data by the platform has a negative association with passive participation in France while being positively associated with it in Turkey. These results are important to understand the participants and to better design successful citizen science platforms
Carugati, Christophe. "Competition law and economics of big data : a new competition rulebook". Thesis, Paris 2, 2020. http://www.theses.fr/2020PA020003.
Texto completo da fonteThis thesis addresses Big Data issues in competition law in three chapters. Chapter one proposes new economic tools to define the relevant market and the market power in the data-driven economy. It argues the need to reform the relevant market and the market power by considering new tools and a menu of key features relevant to the market power. Chapter two proposes new law and economics analysis for data-driven antitrust and merger practices. It considers debated topics related to the integration of privacy in the assessment of antitrust and merger practices, algorithmic collusion and pre-emptive mergers. It argues the need to integrate privacy in any data-driven antitrust and merger practices as data imply necessarily privacy and data protection issues. Finally, chapter three proposes to regulate the digital economy. It demonstrates that the economy is highly concentrated and that the markets cannot correct themselves market failures. It analyzes recommendations from the government reports (Furman et al, Crémer et al, Schallbruch et al, ACCC report, and Stigler report) and It proposes and discusses other original proposals
Poinsot, Lisa. "Contribution à l'étude de la contrainte du temps dans le contrat de travail". Thesis, Université de Lille (2018-2021), 2021. https://pepite-depot.univ-lille.fr/ToutIDP/EDSJPG/2021/2021LILUD014.pdf.
Texto completo da fonteThe « Contribution to the study of the time constraint in the employment contract » proposes to verify the effects of the representation of time by the Law in the face of the difficulties generated by the evolutions impacting employed labour. Law and time are intrinsically linked: law materialises and objectifies time, while the latter justifies legal innovations. This strong mutual influence of time and law leads us to question the relevance of the legal representation of the employment contract in the face of the massive use of algorithms in salaried work. To answer this question, this study intends to demonstrate the creation of a legal representation of the employment contract due to the perception of time by the Law, as well as the transformation of the perception of salaried work, based on artificial intelligence and digital platforms. An answer is therefore emerging: the legal representation of the employment contract, the result of the action of the Law on time, can serve as a basis for the protection of the worker in the face of the important use of artificial intelligence and digital platforms. The adaptation of the legal representation of the employment contract would make it possible to benefit from the advantages of these technological advances while supervising their use
Fraslin, Marie. "Evaluating the capacity of a virtual r&d community of practice : The case of ALSTOM power hydro". Thesis, Grenoble, 2013. http://www.theses.fr/2013GRENI059/document.
Texto completo da fonteIn this dissertation, we explore the potential of a forum to support collaboration and knowledge sharing among Virtual Communities of practice. We thus propose a coding scheme based on the Rainbow model and test it in order to analyze the content of two forums of R&D VcoP. We demonstrate that a forum supports asynchronous argumentative activities and thus enhances global collaboration and knowledge sharing among R&D VcoP members. We then propose an enriched model based on the work of Line Dube and tested it to characterize the R&D VcoP studied. We prove that the community configuration has a direct impact on the online dynamic of the community. We point out the main factors that play a key role in fostering online collaboration and knowledge sharing between R&D Virtual community members
Aragón, Pablo. "Characterizing online participation in civic technologies". Doctoral thesis, Universitat Pompeu Fabra, 2019. http://hdl.handle.net/10803/668042.
Texto completo da fonteEsta tesis constituye una de las primeras investigaciones en caracterizar la participación online en tecnologías cívicas, un tipo de plataforma cada vez más popular en Internet que permite a la ciudadanía nuevas formas, a una mayor escala, de participación política. Dadas las oportunidades de las tecnologías cívicas para la gobernanza democrática, cabe señalar que su diseño, al igual que el de cualquier plataforma online, no es neutral. La forma en que se presenta la información o se permite la interacción entre las usuarias puede alterar en gran medida los resultados de la participación. Por este motivo, analizamos el impacto de diferentes intervenciones en tecnologías cívicas en relación a las vistas de las conversaciones online, los criterios de ordenación en rankings de peticiones e interfaces deliberativas. Dado que estas intervenciones fueron llevadas a cabo por los propios equipos de desarrollo, los análisis han requerido desarrollar nuevos métodos computacionales y estadísticos, a la vez que se han ampliado modelos generativos de hilos de discusión para caracterizar mejor la dinámica de las conversaciones online. Los resultados de los diferentes estudios de caso destacan el impacto social y político de estas intervenciones, sugiriendo nuevas líneas de investigación en el futuro y la necesidad de desarrollar un paradigma de experimentación ciudadana para la democracia.
Aquesta tesi és una de les primeres investigacions que té per objecte la caracterització de la participació en línia en tecnologies cíviques, un tipus de plataforma cada vegada més popular a Internet que permet a la ciutadania noves formes, a major escala, de participació política. Donades les oportunitats de les tecnologies cíviques per a la governança democràtica, cal assenyalar que el seu disseny, com el de qualsevol plataforma en línia, no és neutral. La forma en què com es presenta la informació o es permet la interacció entre les usuàries pot alterar en gran mesura els resultats de la participació. Per aquest motiu, analitzem l'impacte de diferents intervencions en tecnologies cíviques en relació amb les vistes de conversa en línia, els criteris d'ordenació en rànquings de peticions i amb interfícies deliberatives. Atès que aquestes intervencions van ser dutes a terme pels propis equips de desenvolupament, les anàlisis han requerit desenvolupar nous mètodes computacionals i estadístics, alhora que s'han ampliat models generatius de fils de discussió per caracteritzar millor la dinàmica de les converses en línia. Els resultats dels diferents estudis de cas destaquen l'impacte social i polític d'aquestes intervencions, suggerint noves línies d'investigació en el futur i la necessitat de desenvolupar un paradigma d'experimentació ciutadana per a la democràcia.
Cette thèse constitue l'une des premières recherches sur la caractérisation de la participation en ligne à des technologies civiques, un type de plateforme de plus en plus populaire sur Internet qui permet aux citoyens de nouvelles formes, à plus grande échelle, de participation politique. Compte tenu des opportunités offertes par les technologies civiques dans la gouvernance démocratique, il convient de noter que leur design, comme celui de toute plateforme en ligne, n'est pas neutre. La façon dont l'information est présentée ou l'interaction entre les utilisateurs est permise peut grandement modifier les résultats de la participation. Pour cette raison, nous analysons l'impact de différentes interventions dans le domaine des technologies civiques par rapport à l’agencementaux des conversations en ligne, aux critères d'ordre de classement des pétitions et aux interfaces délibératives. Comme ces interventions ont été réalisées par les équipes de développement correspondantes, les analyses ont nécessité de développer nouvelles méthodes informatiques et statistiques, tout en élargissant les modèles génératifs de fils de discussion afin de mieux caractériser la dynamique des conversations en ligne. Les résultats des différentes études de cas mettent en évidence l'impact social et politique de ces interventions, suggérant de nouveaux axes de recherches futures et la nécessité de développer un paradigme d'expérimentation citoyenne pour la démocratie.
Morrongiello, Caroline. "De l'empowerment à l'engagement du client sur les plateformes en ligne : ou comment favoriser l'activité des clients sur Internet". Phd thesis, Université de Grenoble, 2014. http://tel.archives-ouvertes.fr/tel-01071185.
Texto completo da fonteMessaoudi, Kamel. "Traitement des signaux et images en temps réel : "implantation de H.264 sur MPSoC"". Phd thesis, Université de Bourgogne, 2012. http://tel.archives-ouvertes.fr/tel-00905872.
Texto completo da fonteCrépeau, Rousseau Ariane. "Développement et validation d'un modèle de simulation numérique personnalisé à une athlète de plongeon". Thèse, 2013. http://hdl.handle.net/1866/10402.
Texto completo da fonteCoaches need tools to better understand the mechanics of twisting somersaults and improve their knowledge and their athletes’ performance. The aim of this thesis was to provide them with a computer simulation model of aerial movements. An elite diver was modelled as a 17-segment 42-degree of freedom angle-driven model. The model was personalised to the diver so that simulation outputs could be compared with her actual performance. Input data were recorded by a 17-camera motion capture system sampled at 300 Hz. The joint angle time histories were reconstructed using an extended Kalman filter. The model was successfully evaluated and shown to produce realistic movements, with overall root-mean-square error of 20° (somersault) and 9° (twist) between reconstructed body kinematics and the corresponding simulations for eight dives. Finally, a workshop based on the simulation was offered to coaches and showed potential to improve their knowledge since the mean post-test result was increased by 11 %.
Crosset, Valentine. "Être visible sur et par internet : le cas de l'État islamique". Thesis, 2020. http://hdl.handle.net/1866/24778.
Texto completo da fonteThis thesis focuses on the visibility of extremist groups on the internet. While several studies have focused on describing the different uses of digital technologies by radical groups and the way the internet would operate as a catalyst for radicalization, few studies have sought to analyze the constitutive relationship between the technical apparatus and the militant extremist. The objective of the thesis is to renew the visibility model of groups classified as extremists, taking into account the mutual reconfigurations between digital platforms and the militant groups. At a theoretical level, our study is situated at the intersection of actor-network theory (ANT), software studies and Lucy Suchman’s work (2007) on the dynamic reconfiguration of mutual and permanent relationships between humans and machines. Based on the case study of the Islamic State, this analysis, lasting one and a half years, was anchored in data from an ethnographic research field. The survey consists of non-participant observation of several digital platforms exploited by the jihadist group, online archiving and analysis of online traces, as well as a documentary corpus. Our results contribute to better understanding how groups qualified as extremist develop their visibility on digital platforms, by emphasizing that it is relational, technical and conflictual. First of all, our study demonstrates the evolution to a more complex development of the resources used to obtain visibility. The online visibility of the Islamic state requires a vast network of actors, such as media specialists, activists, cybersecurity specialists and botnets. For this reason, offline and online, decentralized and centralized processes are combined. The analysis of their daily practices shows that the work of Islamic state militants to obtain visibility strive at amplification and abundance of their information flow. Their goal is to inundate social media platforms with their contents, conducting a “media war”. Furthermore, the results obtained suggest that developing visibility is complex due to a series of constraints and enemy forces that thwart the Islamic State project, such as moderation of contents as an example. At the same time, our study shows that the presence of this type of users has resulted in the redesign of the regulation of these technologies, making them more restrictive. Finally, the results reveal that the Islamic state militants are actively working to put in place resistance tactics in order to limit the negative effects of that moderation. In a second step, the thesis focuses on the forms of visibility evolving from this technical mediation between activists and digital platforms. We suggest the concept of technical visibility to highlight the online visibility of political opinions. This type of visibility is based on the deployments of a technical rationality. Therein the creation of visibility becomes a specialized activity using the technical as well as mechanized dimensions of digital technologies, each with their own mode of normativity. If technical visibility gives users the possibility to develop their visibility, the thesis expresses certain reservations as to the real value of this “ faire-voir ”. It shows that this type of technical visibility, due to its characteristic quest for efficiency and abundance of information, generalizes bulk, aggressive, or deceptive activity. This results in new forms of domination and asymmetry. We therefore argue that it could jeopardize democracy.