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E-Supply Chain et productivité : le cas de la distribution alimentaire
No full textInternational audienceCe papier analyse d’une part les transferts d’activités constatés au sein de la supply chain alimentaire entre consommateurs, distributeurs et fournisseurs suite au développement des cybermarchés, et d’autre part en évalue les incidences sur la productivité de chaque acteur. L’objectif est l’étude de la productivité dans un contexte multicanal et dans une perspective holistique sur l’intégralité de la supply chain. Ce travail permettra donc une meilleure réflexion sur d’éventuelles améliorations de la gestion globale de la supply chain dans une stratégie transcanal des différents canaux marketing
Risque et lancement de produits nouveaux : l'apport de la cognition sociale implicite
No full textoai:HAL:hal-00956958v1The launch of an innovation carries a considerable element of risk, as new product failure rates are extremely high. Among the reasons for new product failure is poor market research. We demonstrate that a joint measure of explicit attitude (deliberate evaluation which is accessible to introspection) and implicit attitude (indirect and automatic evaluation) increases market research reliability and therefore reduces risks associated with product innovation.Compte tenu du taux d'échec élevé des produits nouveaux, lancer une innovation représente un risque majeur. Une raison de ces nombreux échecs est la médiocre qualité des études marketing. Nous montrons qu'une double mesure de l'attitude, explicite (évaluation délibérée accessible à l'introspection) et implicite (évaluation automatique et indirecte) permet d'augmenter la fiabilité des études et de diminuer ainsi les risques liés à l'innovation
Stock Spams: Another Kind Of Stock Prices Manipulation
No full textInternational audienceThis research investigates the market reaction to an information-based manipulation called stock spams. The impact is focused on the liquidity variable which is measured by Amivest ratio. Using the event study methodology on a sample of penny stocks for the period February 2006 through October 2008, our findings suggest positive and significant abnormal liquidities for stocks targeted by manipulators during the event window. Robustness checks were performed using a non-parametric test. These results support the thesis that this kind of manipulation is a very flourishing business that manipulators exploit by simply purchasing stocks at low prices and selling them at higher prices
Sustainable purchasing and supply management: a structured literature review of definitions and measures at the dyad, chain and network levels
No full textInternational audienceThis paper provides a structured literature review of sustainability in purchasing and supply management, moving beyond the traditional environmental and social sustainability. The paper reviews the concept of sustainability at three levels of inter-organizational analysis - i.e. dyad, supply chain and network. The paper distils the nature and scope of existing research and synthesizes measures used to research sustainability across organizational boundaries. This literature review systematically analyzes existing literature. In particular, the review focuses on definitions and measures of sustainable purchasing and supply management to obtain an accurate view of current research. This paper uncovers two distinct trends in the type of research carried out. First, internal or dyadic issues are in focus and second, a tendency to deal with environmental, as opposed to social, sustainability. Despite the need to look beyond the dyad given the risks associated with the extended network, few studies do so in any of the sustainability dimensions. This review is limited by the method employed focusing on definitions and measures. Although the review considers supply chain and network research, it does so purely from a purchasing perspective, thus excluding issues such as logistics and transport. The paper identifies areas open to future research and provides practical insights into how sustainable purchasing and supply are measured. It also synthesizes existing measures of sustainability at different levels and organizes these into a taxonomy. The paper examines studies across multiple levels of analysis and integrates multiple fields of knowledge to show how research on sustainability in purchasing and supply is structured
The effects of unbalancing operation time variability on the performance of unreliable lines
No full textInternational audiencePurpose - The purpose of this paper is to investigate the performance of unpaced unreliable production lines that are deliberately unbalanced in terms of their coefficients of variation (CVs). Design/methodology/approach - A series of simulation experiments were carried out for five and eight station lines with mean buffer space set at one, two, four and six units. CVs were allocated in 12 different configurations for each of these lines. Findings - The results show that the best unbalanced CV patterns in terms of throughput rates or idle times as compared to a balanced line counterpart are those where the steadiest stations are concentrated near the centre of the line. On the other hand, either concentrating the steadier operators towards the centre or close to the end of the line gives best average buffer level results. Practical implications - The results provide guidelines for production line managers when designing unpaced unbalanced lines depending on their performance aims. Originality/value - The investigation of the effects of unbalancing CVs in unreliable lines has not previously been studied and can provide insights into how best to place workstations with differing variability along the line
Unpaced serial production lines with two simultaneous sources of imbalance - Their operating characteristics
No full textThis paper investigates the behaviour of unpaced serial production lines with two concurrent imbalance sources, namely, lines that are simultaneously unbalanced with respect to either their work time means (MTs) and variability - as depicted by the coefficients of variation of processing times (CVs), their MTs and buffer capacities (BCs), or their CVs and BCs. The lines were simulated under stable operating conditions with different values of line length, buffer capacity, coefficient of variation, degree of imbalance, as well as a variety of imbalance patterns. Making use of a number of statistical methods, idle time and average buffer level output data were analysed and compared to a balanced line counterpart. Conclusions concerning the relationships among the exogenous and endogenous variables were made. For the MT and CV imbalance, the configuration providing the lowest idle time turned out to be an inverted bowl pattern for MT, along with a bowl-shaped arrangement for CV, whereas the best configuration that generally generates low average buffer levels was found to be an MT decreasing order, together with a CV bowl allocation. As for unbalanced MTs and BCs, it was found that in terms of idle time the best unbalanced pattern is an MT bowl configuration, coupled with a distribution of buffer capacity as evenly as possible. On the other hand, for average buffer level the best pattern was a monotone decreasing MT order, together with an ascending buffer size order. As regards CV and BC imbalance, the most superior pattern with respect to idle time was identified as a bowl-shaped CV configuration, combined with a buffer placement whereby more buffer capacity is concentrated at the beginning of the line, but for average buffer level the most favourable pattern was a bowl-shaped CV assignment, together with a buffer arrangement under which the buffers are concentrated towards the end of the line
Intrinsic motivations, self-esteem, and luxury goods consumption
No full textInternational audienceDespite the dramatic growth of the luxury market over the past two decades, luxury consumer research remains fragmentary and scant. To address this knowledge gap, this study investigates consumers' intrinsic motivations for purchasing luxury goods. Data were collected from 587 consumers and analyzed using structural equation modeling. The results show that consumers who are primarily intrinsically motivated tend to purchase luxury products for superior quality and self-directed pleasure. The findings also demonstrate that self-esteem, an important concept in psychology and consumer behavior but rarely studied in luxury research, relates strongly to self-directed pleasure
The impact of stock spams on volatility
No full textInternational audienceThis article is dedicated to study the impact of stock spams through the analysis of the variations of volatility. Our sample contains 110 firms quoted on emerging market, namely the penny stock market. The results, based on event study methodology and Generalized Autoregressive Conditional Heteroscedastic (GARCH) modelling, show positive and significant changes in volatility; a widening of the variation (lowest price–highest price) was noticed following the consignment of messages by the spammers. The sending of stock spams affected the behaviour of investors, thus indicating that the spamming activity is a lucrative business
The behaviour of unpaced production lines with unequal means processing times, viriability, or buffer capacities
No full textIn this paper we study the operating behaviour and performance of reliable, unpaced and unbalanced serial production lines with either imbalanced service time means, unequal coefficients of variation, or uneven buffer capacities. The lines were simulated with various values of line length, buffer storage size, degree of imbalance, coefficient of variation, along with a number of imbalance configurations. The primary measures of efficiency were idle time and average buffer level. Output data from the discrete event simulation of such lines under their steady-state mode of operation were analyzed using a set of statistical methods. Various relationships between the independent and response variables, rankings of configurations and comparisons with balanced lines were obtained. For the mean processing times imbalance, it turned out that a bowl-shaped arrangement provides smaller idle time amounts and lower average buffer levels than those of a balanced line counterpart. As regards the variability imbalance, it was found that the best configurations are respectively, a bowl allocation and a monotone decreasing order, with the first resulting in decreased idle times and the second leading to lower average buffer levels than those of a balanced line. As far as the buffer size imbalance is concerned, it was concluded that the most advantageous patterns that generate lower idle times and average buffer levels as compared to a balanced line are to respectively distribute total available buffer capacity as evenly as possible along the buffers and to allocate more buffer capacity towards the end of the line