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: Underwater cables: the backbone of cyberspace
No full textInternational audienceAt the bottom of our oceans lie thousands of kilometers of underwater cables, the backbone of cyberspace.These infrastructures allow us to communicate and was initially guarded by traditional operators. GAFA and BATX are now investing to control these essential asset to their strategy. They remain an issue of power and sovereignty for the states.Au fond de nos oceans reposent sur des milliers de kilomètres, les autoroutes du cyberespace. Ces infrastructures permettent aux hommes de communiquer. D'abord chasse gardée des opérateurs, les GAFA et les BATX investissent pour contrôler ces infrastructures indispensables à leur stratégie. Ils restent un enjeu de puissance et de souveraineté pour les états
Liquid retail: cultural perspectives on marketplace transformation
No full textInternational audienceInspired by Bauman’s notion of “liquidity,” we problematize the socio-cultural dynamics taking place in contemporary retail. The notion of liquid retail enables researchers to untangle marketplace transformation and to highlight developments centred around markets and market-actors that jointly transform each other. This introduction underlines, as a point of departure, recent developments in retailing that have been marked by the corrosion of fixity and boundaries. We provide a short synopsis of marketplace transformation and liquid retail, from a socio-cultural perspective, and summarize the papers included in this special issue
The Impact of the French Doctrine of Significant Imbalance on International Business Transactions
No full textThis article examines the concept of “significant imbalance” (SI) under French law and its impact on international business transactions. “Significant imbalance” is a legal standard meant to assess whether a contractual clause is unfair (abusive). Although initially restricted to consumer law, it has been extended to general contract law with the implementation of a reform entered into force on 1st October 2016. Previously, the Commercial Court of Paris in the ruling Ministry of Economy et al. v. Expedia, Inc. et al. (2015) had qualified SI as an “overriding mandatory provision” (loi de police) under EU Regulation No. 593/2008 on the applicable law to contractual obligations (Rome I). As a consequence, SI became operative in respect of international contracts despite an express choice of a foreign governing law made by the parties to the transaction. This article argues that, as a result of Expedia and the 2016 reform, French courts can interfere with international business transactions by striking down contractual terms that they deem unfair according to the SI standard. The analysis focuses on two key issues. On the one hand, notwithstanding recent judicial precedents, SI still fails to provide a reliable test for predicting which clauses or contracts are at risk of being deemed unfair. On the other hand, the legal arsenal supporting French legislator’s disapproval of SI allocates great power to French courts and the French government to pursue tort lawsuits against foreign companies allegedly oppressing their commercial partners with SI clauses. Empirical evidence shows that these actions are highly successful compared to those commenced by private actors. The article concludes that all these aspects, together with SI’s turbulent case-law throughout the years, will sprout uncertainty in international business transactions and may eventually disparage France in the global competition in such a field
The Effects of Mental Accounting on Project Performance
No full textProblem Definition:Project managers are responsible for setting and then revising projects' goals. As uncertainty related to project performance is resolved, a project manager is tasked with comparing ongoing costs, and potentially achieved scope, to a baseline plan. We question whether project managers can rationally anticipate and track this revision process.Academic/Practical Relevance:In practice, projects often fail to meet their goals and are subject to changes in scope, cost, and scheduled time. We consider the implications of behavioral tendencies and the revision strategy on decisions made and on overall project performance.Methodology:Our stylized model compares a rational project manager to a behavioral one. Specifically, we offer a framework for modeling mental accounting—which includes loss aversion and reference point updating—and narrow framing. We use the model to explore how project-level decisions are made.Results:We show that mental accounting results in insufficient adjustments of project scope and cost during revisions, and prevents abandoning projects even when doing so is optimal. Ultimately, mental accounting and narrow framing decrease projects' actual profits.Managerial Implications:We offer practical prescriptions for mitigating harmful effects of loss aversion, reference-point updating, and narrow framing. Beyond training, hiring less loss averse project managers, and practicing scenario planning, we show that reviewing a project using a cost milestone instead of a scope milestone helps maintain the reference cost equal to the budgeted cost, thereby inducing overall better decisions
Terres rares : ce qui est rare risque de coûter cher!
No full textInternational audienceTerres rares : le grammairien dirait qu’il s’agit d’une métonymie, car elles ne sont ni terres ni rares. Il s’agit d’une trentaine de métaux dont on vous épargnera la liste, ayant des propriétés physiques et magnétiques exceptionnelles. Ils sont contenus de façon infinitésimale dans des roches contenant d’autres minerais
Combining probability with qualitative degree-of-certainty metrics in assessment
No full textInternational audienceReports of the Intergovernmental Panel on Climate Change (IPCC) employ an evolving framework of calibrated language for assessing and communicating degrees of certainty in findings. A persistent challenge for this framework has been ambiguity in the relationship between multiple degree-of-certainty metrics. We aim to clarify the relationship between the likelihood and confidence metrics used in the Fifth Assessment Report (2013), with benefits for mathematical consistency among multiple findings and for usability in downstream modeling and decision analysis. We discuss how our proposal meshes with current and proposed practice in IPCC uncertainty assessment
Psychophysical Foundations of the Cobb-Douglas Utility Function
No full textRelying on a literal interpretation of Weber's law in psychophysics, we show that a simple condition of independence across good categories implies the Cobb-Douglas preferences
The Allais Paradox: What It Became, What It Really Was, What It Now Suggests to Us
No full textWhereas many others have scrutinized the Allais paradox from a theoretical angle, we study the paradox from an historical perspective and link our findings to a suggestion as to how decision theory could make use of it today. We emphasize that Allais proposed the paradox as a normative argument, concerned with "the rational man" and not the "real man", to use his words. Moreover, and more subtly, we argue that Allais had an unusual sense of the normative, being concerned not so much with the rationality of choices as with the rationality of the agent as a person. These two claims are buttressed by a detailed investigation – the first of its kind – of the 1952 Paris conference on risk, which set the context for the invention of the paradox, and a detailed reconstruction – also the first of its kind – of Allais's specific normative argument from his numerous but allusive writings. The paper contrasts these interpretations of what the paradox historically represented, with how it generally came to function within decision theory from the late 1970s onwards: that is, as an empirical refutation of the expected utility hypothesis, and more specifically of the condition of von Neumann-Morgenstern independence that underlies that hypothesis. While not denying that this use of the paradox was fruitful in many ways, we propose another use that turns out also to be compatible with an experimental perspective. Following Allais's hints on "the experimental definition of rationality", this new use consists in letting the experiment itself speak of the rationality or otherwise of the subjects. In the 1970s, a short sequence of papers inspired by Allais implemented original ways of eliciting the reasons guiding the subjects' choices, and claimed to be able to draw relevant normative consequences from this information. We end by reviewing this forgotten experimental avenue not simply historically, but with a view to recommending it for possible use by decision theorists today
Impact of Workforce Flexibility on Customer Satisfaction: Empirical Framework & Evidence from a Cleaning Services Platform
No full textProblem definition: Contrary to classic applications of matching theory, in most contemporary on-demand service platforms, matches can not be enforced because workers are flexible – they choose their tasks. Such flexibility makes it difficult to manage workers while keeping customers satisfied. We build a framework to compare platform matching policies with less flexible and more flexible workers, and empirically quantify by how much worker flexibility hurts customer satisfaction and customer equity.Academic/Practical relevance: In academic literature, there is no established framework that allows for the comparison of matching policies in on-demand platforms. Further, the link between worker flexibility and customer satisfaction is understudied.Methodology: We propose a tripartite framework for empirical evaluation and comparison of the operational policies with different degrees of worker flexibility. Step 1: Predictive modeling of customer satisfaction based on estimation of individual unobservable characteristics: customer difficulty and worker ability (item-response theory model). Step 2: Evaluation of the effect of matching policy (under a given level of flexibility) on customer satisfaction (bipartite matching). Step 3: Quantification of the associated monetary impact (customer lifetime value model).Results: We apply our framework to the dataset of one of the world's largest on-demand platforms for residential cleanings. We find that customer difficulty and cleaner ability are good predictors of customer satisfaction. Granting full flexibility to workers reduces customer satisfaction by 3% and customer lifetime revenue by 0.2%. We propose a family of matching policies that provide sufficient flexibility to workers, while alleviating 75% of the detrimental effect of worker flexibility on customer satisfaction.Managerial implications: Our results suggest that, in platforms with flexible workforce, the presence of worker and customer heterogeneity reduces customer satisfaction through matching inefficiency. Our empirical framework helps practitioners to decide on the right level of worker flexibility and the means for achieving it
The Effect of Dockless Bike-Sharing on Public Transportation: An Empirical Study
No full textWe examine the impact of a new mobile-based, dockless bike-sharing service on public transportation. In contrast to traditional rental bikes that are parked at fixed stations, the dockless bikes can be picked up and returned at literally anywhere. This dockless feature of the shared bikes likely provides a solution to the last mile problem, potentially making it a complement to public transportation. Assembling a unique panel data of shared-bike rides and subway traffic, we estimate the relationship between shared-bike ridership and public transportation. Our results show that increases in shared-bike rides lead to increases in subway traffic. This positive effect is stronger for peak hours during weekdays and non-peak hours during weekends. We argue this effect is most likely driven by shared bikes promoting public transportation use and substituting for private cars (substitution effect) and also stimulating new travel (stimulating effect). Overall, we find that dockless shared bikes, in contrast to most of the other sharing economy phenomenon, acts as a complement rather than a substitute for public transportation. In addition, increased use of dockless shared bikes has a positive societal impact, leading to less urban congestion and better environmental protection