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Social Networking Continuance: When Habit Leads to Information Overload
No full textIn this paper, we propose an explanatory model of the continuance intention to use social networking sites (SNS). Our aim is to extend the post adoptive model by incorporating Habit and Information Overload as antecedents to SNS continuance intention. A quantitative approach based on an online survey administered to 320 executive managers in France confirms the positive role of habit in generating information overload and in positively affecting SNS continuance intention. The results also show that satisfaction and perceived usefulness do not seem to play any significant role.nonouirechercheInternationa
Méthodologie d’évaluation et d’analyse des conflits dans les espaces ruraux et périurbains
No full textLes données permettant d’analyser la conflictualité sont peu nombreuses, et souvent lacunaires, pour deux raisons principales : le faible intérêt marqué pour ce domaine jusqu’aux années 2000 et la forme complexe prise par les conflits (tribunaux, médiatisation, violence…), ce qui interdit l’usage d’une seule variable représentative. Le chercheur doit donc construire ses propres données. Notre programme d’étude sur les conflits des espaces naturels, ruraux et périurbains sur le territoire français associe plusieurs équipes françaises de l’INRA, de l’Irstea, du CIRAD, de différentes universités et écoles d’agronomie, et a abordé différentes problématiques liées à la conflictualité des espaces naturels, ruraux et périurbains sur le territoire français. La singularité de cette approche réside dans une méthode de repérage des conflits complexe et composite, alliant différentes sources et une méthodologie spécifique pour obtenir l’image la plus fidèle possible de la conflictualité au sein d’une zone ou d’une espace donnés. Pour repérer les conflits d’usage de l’espace, nous en avons donné une définition opérationnelle, dans le but de reconnaître et réunir les éléments et évènements conflictuels, les classer et tracer les profils conflictuels d’une zone donnée. Nos recherches sont menées dans les territoires ruraux et périurbains. Elles concernent les conflits et tensions autour des biens publics de consommation (l’air, les aménités du paysage et les fonctions de la nature), des ressources (l’eau ou l’énergie), des déchets et des pollutions, ainsi que de l’espace de localisation et de voisinage entre individus ou activités.FrançaisnonouirechercheNationa
The ethical stakes in monetary valuation for conservation purposes
No full textThe involvement of economic approaches is increasingly pervasive in conservation practices, from environmental policies to procedures determining the choice of conservation projects. The literature on the ethical weaknesses of economic approaches suggests to question the self-evidence of these interactions. However, economics encompasses a variety of approaches and methods, with unclear ethical underpinnings. This article contributes to these debates through a focused clarification of the ethical presuppositions of monetary valuations methods. This choice reflects that monetary valuation studies are expanding and provide numerous opportunities of interactions with conservation biologists. Identifying and understanding their ethical presuppositions is therefore pivotal for conservation biologists. For that purpose, we provide a glossary of the ethical concepts underpinning the current monetary valuation methods. We show that using a given monetary valuation method commits to endorse specific ethical stances. We then develop a practical case study: the conservation of a population of the endangered plant Leucanthemum burnatii Briq. & Cav. in a semi-natural site in the French Alps. We describe the steps that a conservation biologist could follow to decide whether she should seize opportunities to work with economists implementing monetary valuations in this setting. These stepping stones structure the approach that conservation biologists can deploy to identify the ethical stakes of conservation/economics interactions. This approach can also prove useful for conservation biologists to reflexively clarify their own ethical motivations. By appropriating this approach, conservation biologists can equip themselves to enter public debates to legitimize the usage of scientific results to improve collective decision-making on conservation issues.nonouirechercheInternationa
The liquidity regimes and the prepayment option of a corporate loan in the finite horizon case
No full textWe investigate the prepayment option related to a corporate loan. The default intensity of the firm is supposed to follow a Cox-Ingersoll-Ross (CIR) process and the short interest rate is assumed constant. A liquidity term that represents the funding costs of the bank is introduced and modeled as a continuous time discrete state Markov jump process. The prepayment option is an American option with the payoff being an implicit function of the parameters of the problem. We give a verification result that allows to compute the price of the option. Numerical results are completely consistent with the theory; it is seen that the exercise domain may entirely disappear during such a liquidity crisis meaning that it is not optimal for the borrower to prepay. The method allows to quantify and interpret these findings.nonnonouirechercheInternationa
‘License to Expose?’ Occupational Exposure Limits, Scientific Expertise and State in Contemporary France
No full textnonouirechercheInternationa
When Behavioral Portfolio Theory Meets Markowitz Theory
No full textThe Behavioral Portfolio Theory (BPT) developed by Shefrin and Statman is often confronted to the Markowitz's Mean Variance Theory (MVT). Although the BPT optimal portfolio is theoretically not mean variance efficient, some recent studies show that under the assumption of normally distributed returns, MVT and some models incorporating features of BPT can generate similar asset allocations. In this paper, we compare the asset allocations generated by BPT and MVT without restrictions. Using US stock prices from the CRSP database for the 1995-2011 period, we empirically determine the BPT optimal portfolio. We show that the Shefrin and Statman's optimal portfolio is MV efficient in more than 70% of cases. However, our results also indicates that MV investors will typically not select the BPT portfolio as this portfolio is always associated with a high return and an important level of risk. We show that the risk aversion coefficient of the BPT portfolio is up to 60 times smaller than the risk aversion degree of usual MV investors.nonnonouirechercheInternationa
Corporate social disclosure and legitimation strategy : a longitudinal study of Pechiney
No full textThis paper deals with corporate social disclosure (CSD). It consists in a longitudinal study of Pechiney CSD practices. Our research aims at identifying the determinants of such practices. Particularly, we document the link between CSD practices and public's concern.Theoretical framework is derived from legitimacy theory. Based on seminal work of Lindblom (1994), Deegan, Rankin & Tobin, (2002), we argue that CSD can be considered as a legitimation strategy. Indeed, CSD is a means used by firms to inform its stakeholders and also to manage public impressions as demonstrated by Neu, Warsame & Pedwell (1998).Regarding methodology, a content analysis of newspapers and annual reports allows the measurement of respectively public impression and CSD, on a period covering the second half of the 20th century.According to our questioning, the results confirm a strong link between on the one hand public opinion and on the other hand environmental and social disclosure. So, our theoretical framework seems relevant in explaining the use of CSD as a legitimation strategy.Beyond this finding, our analysis of verbatim shows that, contrary to a widespread belief, CSD is not a new phenomenon.Considering the number of studies dealing with CSD, our main contribution consists in offering a deep investigation based on a case study of a French company. Some perspectives proceed from this work. For instance, we suggest to extend the scope of determinants including events related to firm's story.ouinonouirechercheInternationa
The computational complexity of dominance and consistency in CP-nets
No full textWe investigate the computational complexity oftesting dominance and consistency in CP-nets. Upuntil now, the complexity of dominance has beendetermined only for restricted classes in which thedependency graph of the CP-net is acyclic. However, there are preferences of interest that definecyclic dependency graphs; these are modeled withgeneral CP-nets. We show here that both dominance and consistency testing for general CP-netsare PSPACE-complete. The reductions used in theproofs are from STRIPS planning, and thus establish strong connections between both areas.ouinonouirechercheInternationa
Ageing and the Demand for Life Insurance : An Empirical Investigation using French Panel Data
No full textThe age structure of the French population has been experiencing dramatic changes over the past decades and is likely to do so in a near future. The increasing proportion of elder people may modify the saving behaviour of French households. The level of saving, as well as its composition, may be altered by ageing of the French population. This paper investigates the relationship between age structure and the demand for life insurance products using an econometric estimation of French survey data (Patrimoine 1998 of the National Institute of Statistics and Economic Studies (INSEE)). More precisely, we try to identify the significant demographic, economic and financial factors influencing this demand (age, income, household wealth, marital status, occupational status and education…). Following a methodology developed in a companion article, this paper begins with a characterisation of household accumulation profile in France. The paper then estimates a Probit model to exhibit the determinants of the probability of life insurance holding, and an ordinary least squares procedure to explain the amount of wealth held in life insurance, according to the previously identified significant variables. The results suggest a robust relationship between demographic structure and the demand for life insurance.ouinonouirechercheInternationa
Generalized stochastic target problems for pricing and partial hedging under loss constraints - Application in optimal book liquidation
No full textWe consider a singular with state constraints version of the stochastic target problems studied in Soner and Touzi (2002) and more recently Bouchard, Elie and Touzi (2008), among others. This provides a general framework for the pricing of contingent claims under risk constraints. Our extended version perfectly suits to market models with proportional transaction costs and to order book liquidation issues. Our main result is a PDE characterization of the associated pricing function. As an example of application, we discuss the evaluation of VWAP-guaranteed type book liquidation contracts, for a general class of risk functions.ouinonouirechercheInternationa