HAL-Artois
Not a member yet
27242 research outputs found
Sort by
Price–Quantity Competition in a Duopoly Market With Price Similarities
No full textInternational audienceWe introduce a form of consumers' bounded rationality, price similarities , in a duopoly market with price–quantity competition. Price similarities occur when consumers do not react to slight differences in prices. In this case, firms' demands are determined by a sharing rule that depends on the quantities produced. Assuming a general form of the proportional sharing rule, we show that a pure strategy Nash equilibrium for the price–quantity game materializes if, and only if, price similarities are in place. We also show that there are two kinds of equilibrium. In the first kind, total supply equals total demand. By contrast, in the second kind, firms overproduce. Finally, we show how to compute the minimum level of the price similarities phenomenon necessary to ensure equilibrium existence given the market conditions
Discours juridiques, genre et histoire
No full textCe numéro présente les actes enrichis du colloque organisé du 6 au 8 décembre 2023 à la faculté de droit de l'université de Douai ainsi que des contributions inédites
The limits of behavioral nudges to increase youth turnout: Experimental evidence from two French elections
No full textInternational audienceThere is a significant gap in turnout between young people and older voters. The failure to instill a voting habit at an early age may have long term consequences in terms of future political participation as well as on other civic behaviors. Using a pre-registered online experiment with 3790 subjects, we implemented behavioral interventions aiming to stimulate youth turnout in the 2022 French presidential election. We rely on an innovative incentive scheme to measure their consequences on (self-reported) actual voting behavior. We also provide evidence on the effect of one behavioral intervention on youth turnout in a less salient election, the French legislative election that took place two months after the Presidential one. The results from the two experiments show the absence of any differences in turnout between the baseline and the treatment conditions. We investigate several mechanisms that can explain our results
Identification of Spatial Spillovers: Do's and Don'ts
No full textInternational audienceThe notion of spatial spillovers has been widely used in applied spatial econometrics. In this paper, we consider how they can be identified in both structural and causal reduced‐form models. First, discussing the various threats to identification in structural models, we point out that the typical estimation framework proposed in the applied spatial econometric literature boils down to considering spatial spillovers as a side‐effect of a data‐driven chosen specification. We also discuss the limits of blindly relying on interaction matrices purely based on geography to identify the source and content of spillovers. Then, we present reduced forms impact evaluation models for spatial data and show that the current spatial versions of usual impact evaluation models are not fully satisfactory when considering the identification issue. Finally, we propose a set of recommendations for applied articles aimed at identifying spatial spillovers
Chapitre IV : Salaires, Migrations, Développement : l’Afrique entre Lewis, Myrdal et Hirschman
No full textNational audienc
Ten year follow-up of hip resurfacing in patients under thirty years old.
No full textInternational audiencePurposeAs an alternative to total hip arthroplasty (THA), hip resurfacing arthroplasty (HRA) has numerous advantages including low risk of dislocation, preservation of femoral bone stock, and no restrictions on high-impact sports. This study was designed to evaluate the results of HRA performed in patients under 30 years old with a long-term follow-up.MethodsAll HRA performed in patients younger than 30 years at the time of surgery were reviewed with a minimum follow up of two years. The analysis was based on clinical data, patient-recorded outcomes measures, biological and radiological evaluation.ResultsOne-hundred three HRA procedures in 93 patients (77 males and 16 females) were included. Mean age at surgery was 27.7 years (18 to 29.9). The two most frequent indications were osteoarthritis in 52% (54 HRA) and developmental dysplasia of the hip in 19% (20 HRA). There were two revisions: one for femoral aseptic loosening and one for infection. No dislocation or adverse wear-related failures were found. At a mean follow-up of 10.4 years (2-17.4), the mean UCLA activity and Oxford Hip score improved from 5.4 (1 to 7) and 39.9 (25–55) preoperatively to 7.9 (3 to 10) and 15.8 (12–34) postoperatively (p < 0.001), respectively. Kaplan-Meier survival analysis, with revision for any reason as the endpoint, showed a 10.8-year survival rate of 98%.ConclusionThis cohort of HRA in patients under 30 years old is the longest follow-up ever reported. Despite HRA being done in a challenging cohort of patients, it shows excellent survivorship with a low complication rate
An international dataset on organic molecule concentrations in soil and related kitchen garden crops
No full textInternational audienceKitchen garden crops offer many environmental, socio-economic and health benefits but can also result in land use changes that may increase citizens’ exposure to pollutants. In this context, a dataset of organic molecules, based on an analysis of scientific literature was created, entitled BAPPOP (BAse de données sur la contamination des Plantes Potagères par les molécules Organiques Polluantes, i.e. dataset on contamination of kitchen garden plants by organic pollutants). BAPPOP compiles 6246 entries collected from 87 publications and 3 reports linking data on organic molecule’ concentrations in kitchen garden soil and crops. Additional information relative to the conditions for which the data have been obtained complete the dataset: organic molecule descriptions, soil properties, plant descriptions and treatments, experimental and analytical methods, as well as bibliographic information. This dataset is suitable for various stakeholders involved in environmental analyses both to compare site specific results to scientific literature data and secondly to predictively evaluate organic molecule’ concentrations and their transfer to kitchen garden crops based on the soil concentration
Non‐Classical Nitrogen Promoters for Rhodium‐Catalyzed Reductive Hydroformylation: New Efficient Way to Access Polyols From Linseed Oil
No full textInternational audienceThe reductive hydroformylation reaction of polyunsaturated linseed oil using a rhodium precursor associated with a nitrogen compound from five different families (pyridines, imidazoles, trialkylamines, amidines, and guanidines) has been successfully developed. The highest yield of 72% alcohols was obtained with an (Rh/1,2,4,5‐tetramethylimidazole) catalytic system. This value represents the highest yield obtained in this tandem reaction of such a challenging substrate. A deep screening of different nitrogen compounds highlighted the strong influence of their pKa on the reaction kinetics. If the ligand/Rh ratio is too high, the basic character of the ligand overrides its ligating property and leads to deprotonation of the Rh hydride active species, resulting in dormant species that are inactive in the reductive hydroformylation reaction. For each family tested, except for triethylamine, a bell‐shaped curve of alcohol yield versus ligand/Rh ratio was obtained, with a peak position essentially related to the pKa value of the N ‐ligand. This work highlights the efficiency of new families of nitrogen promoters in the HHM reaction catalyzed by rhodium complexes, and in particular in the valorization of bio‐based substrates presenting challenging characteristics such as polyunsaturations. Practical Applications : The (Rh/1,2,4,5‐tetramethylimidazole) catalytic system provided the highest alcohol yield in linseed oil reductive hydroformylation. This system could be applied to other petroleum‐derived olefins or bio‐based substrates containing unsaturations. The value‐added polyols obtained in this study have a wide range of applications in the production of lubricants, surfactants, plasticizers, or polymers
Comparing AI coaching and sales manager coaching: A construal-level approach
No full textInternational audienceArtificial intelligence (AI) can provide salespeople with detailed feedback and recommendations before, during, and after their sales tasks, potentially replacing sales managers. This study uses two experiments, involving 244 and 310 sales professionals, to compare the effects of AI coaching and manager coaching on salespeople's selfefficacy and their intention to use coaching. Drawing on construal-level theory, we show that coaching framed at either a low construal level or high construal level should align with the perceived distance of the coach. The findings reveal that a manager coach employing low construal coaching positively impacts salespeople's selfefficacy, increasing their likelihood of using the coaching. However, low construal coaching is less effective than high construal coaching when delivered by AI, which is perceived as more distant than a manager. While AI coaching holds potential for fostering salespeople's development, sales managers should carefully consider the impact of the completeness and precision of AI coaching