Articles scientifiques

Efficient purchaser incentive when dealing with suppliers implementing continuous improvement plans


International Transactions in Operational Research

juillet 2014, vol. 21, n°4, pp.673-701

Départements : Informations Systems and Operations Management, GREGHEC (CNRS)

Mots clés : Continuous improvement, Dynamic programming, Purchaser incentives, Stochastic decision process

This paper presents incentive schemes in the framework of a collaborative purchasing cost reduction process with a supplier implementing a continuous improvement plan. Using a stochastic decision process formulation, we analyze the structure of the optimal policy and characterize its numerical robustness through numerical applications solved by dynamic programming. Then, we analyze two purchaser incentive schemes observed in practice. First, we describe some theoretical properties of the policies associated with these two schemes (schemes I and II) and show that these policies exhibit nonoptimal structures. Second, we estimate the quantitative loss for typical parameter values and, in particular, we show that for certain businesses this loss is significant. Then, we propose two easy-to-implement improvements (schemes III and IV), which result in near-optimal solutions and a significant impact on purchasing cost performances

Emergence of Power Laws in Online Communities: The Role of Social Mechanisms and Preferential Attachment


MIS Quarterly

septembre 2014, vol. 38, n°3, pp.795-823

Départements : Informations Systems and Operations Management, GREGHEC (CNRS)

Mots clés : Online communities, scale-free, power-law distribution, preferential attachment, social exchange, reciprocity, simulation

Online communities bring together individuals with shared interest in joint action or sustained interaction. Power lawdistributions of user popularity appear ubiquitous in online communities but their formation mechanisms are not wellunderstood. This study tests for the formation of power law distributions via the mechanisms of preferential attachment,least efforts, direct reciprocity, and indirect reciprocity. Preferential attachment, where new entrants favor connectionswith already popular participants, is the predominant explanation suggested by prior literature. Yet, the attribution ofpreferential attachment or any other mechanism as a single unitary reason for the emergence of power law distributionsruns contrary to the social nature of online communities and does not account for diversity of participants’ motivation.Agent-based modeling is used to test if a single social mechanism alone or multiple mechanisms together can generatepower law distributions observed in online communities. Data from 28 online communities is used to calibrate, validate,and analyze the simulation. Simulated communication networks are randomly generated according to parameters foreach hypothesis. The fit of the power law distribution in the model testing subset is then compared against the fit forthese simulated networks. The major finding is that, in contrast to research in more general network settings, neitherpreferential attachment nor any other single mechanism alone generates a power law distribution. Instead, a blendedmodel of preferential attachment with other social network formation mechanisms was most consistent with power lawdistributions seen in online communities. This suggests the need to move away from stylized explanations of networkemergence that rely on single theories toward more highly socialized and multitheoretic explanations of communitydevelopment

Intra-organizational information asymmetry in offshore ISD outsourcing



2014, vol. 44, n°1, pp.94-120

Départements : Informations Systems and Operations Management, GREGHEC (CNRS)

Mots clés : Offshore outsourcing, Agency theory, Information asymmetry, Information system development

Contemporary offshore Information System Development (ISD) outsourcing is becoming even more complex. Outsourcing partner has begun ‘re-outsourcing’ components of their projects to other outsourcing companies to minimize cost and gain efficiencies. This paper aims to explore intra-organizational Information Asymmetry of re-outsourced offshore ISD outsourcing projects.Design/methodology/approach - An online survey was conducted to get an overall view of Information Asymmetry between Principal and Agents (as per the Agency theory).Findings - Statistical analysis showed that there are significant differences between the Principal and Agent on clarity of requirements, common domain knowledge and communication effectiveness constructs, implying an unbalanced relationship between the parties. Moreover, our results showed that these three are significant measurement constructs of Information Asymmetry.Research limitations/implications - In our study we have only considered three main factors as common domain knowledge, clarity of requirements and communication effectiveness as three measurement constructs of Information Asymmetry. Therefore, researches are encouraged to test the proposed constructs further to increase its precision.Practical implications - Our analysis indicates significant differences in all three measurement constructs, implying the difficulties to ensure that the Agent is performing according to the requirements of the Principal. Using the Agency theory as theoretical view, this study sheds light on the best contract governing methods which minimize Information Asymmetry between the multiple partners within ISD outsourcing organizations.Originality/value - Currently, to the best of our knowledge, no study has undertaken research on Intra-organizational Information Asymmetry in re-outsourced offshore ISD outsourcing projects

Introducing competition in healthcare services: the role of private care and increased patient mobility


European Journal of Operational Research

mai 2014, vol. 234, n°3, pp.898-909

Départements : Informations Systems and Operations Management, GREGHEC (CNRS)

Mots clés : OR in government, Health policy, Game theory

We study the operational implications from competition in the provision of healthcare services, in the context of national public healthcare systems in Europe. Specifically, we study the potential impact of two alternative ways through which policy makers have introduced such competition: (i) via the introduction of private hospitals to operate alongside public hospitals and (ii) via the introduction of increased patient choice to grant European patients the freedom to choose the country they receive treatment at. We use a game-theoretic framework with a queueing component to capture the interactions among the patients, the hospitals and the healthcare funders. Specifically, we analyze two different sequential games and obtain closed form expressions for the patients’ waiting time and the funders’ reimbursement cost in equilibrium. We show that the presence of a private provider can be beneficial to the public system: the patients’ waiting time will decrease and the funders’ cost can decrease under certain conditions. Also, we show that the cross-border healthcare policy, which increases patient mobility, can also be beneficial to the public systems: when welfare requirements across countries are sufficiently close, all funders can reduce their costs without increasing the patients’ waiting time. Our analysis implies that in border regions, where the cost of crossing the border is low, “outsourcing” the high-cost country’s elective care services to the low-cost country is a viable strategy from which both countries’ systems can benefit

Le déploiement d’innovations inter-filiales au sein d’une multinationale


Management International

2014, vol. 18, pp.42-58

Départements : Informations Systems and Operations Management, GREGHEC (CNRS)

Mots clés : Déploiement, Innovation, Multinationales, inter-filiale, connaissances tacites / Deployment, Innovation, Multinational corporation, inter-subsidiary, tacit knowledge

Les filiales d’une multinationale doivent concilier adaptation locale et intégration globale. Pour analyser cela, nous proposons la notion de déploiement d’innovations inter-filiales que nous définissons comme l’enchaînement des commercialisations d’une innovation par des filiales situées dans des contextes locaux différenciés, et nécessitant ainsi à chaque fois son adaptation. A partir d’une analyse longitudinale de cinq déploiements d’innovations dans une multinationale, nous mettons en évidence quatre facteurs critiques que nous relions à des dispositifs de construction et de partage de connaissances. Nous discutons ainsi le modèle théorique de transfert de connaissances de Tallmann et Chacar (2011) et en précisons les conditions de mise en oeuvre


Informations Systems and Operations Management

Campus HEC Paris
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Xitong LI

Informations Systems and Operations Management (GREGHEC)

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