Analysis and Optimization of a Combined Make-to-Stock and Make-to-Order Multiproduct Manufacturing System

K. Hadj Youssef, C. VAN DELFT, Y. Dallery

Journal of Applied Mathematics and Decision Sciences

2009, vol. 2009, n°ID 716059

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

We consider a single-stage multiproduct manufacturing facility producing several end-products for delivery to customers with a required customer lead-time. The end-products can be split in two classes: few products with high volume demands and a large number of products with low-volume demands. In order to reduce inventory costs, it seems efficient to produce the high-volume products according to an MTS policy and the low volume products according to an MTO policy. The purpose of this paper is to analyze and compare the impact of the scheduling policy on the overall inventory costs, under customer lead-time service level constraints. We consider two policies: the classical FIFO policy and a priority policy (PR) which gives priority to low volume products over high volume products. We show that for some range of parameters, the PR rule can significantly outperform the FIFO rule. In these ranges, the service level constraints are satisfied by the PR rule with much lower inventory costs.

Applying Regret Theory to Investment Choices: Currency Hedging Decisions

S. Michenaud, B. SOLNIK

CFA Digest

février 2009, vol. 39, n°1, pp.55-56

Départements : Finance

The authors develop a model that has two components of risk: traditional risk (volatility) and regret risk. They apply the model to currency hedging to demonstrate behavior that would be counterintuitive when considering only traditional risk. The model is limited to relatively simple decision constructs because of the intricacy of applying regret theory and is distinctly different from other loss aversion behavioral models.

Approximate Bayesian inference for latent Gaussian models by using integrated nested Laplace approximations

H. Rue, S. Martino, N. CHOPIN

Journal of the Royal Statistical Society: Series B - Statistical Methodology

mars 2009, vol. 71, n°2, pp.319-392

Départements : Economie et Sciences de la décision

Mots clés : Approximate Bayesian inference, Gaussian Markov random fields, Generalized additive mixed models, Laplace approximation, Parallel computing, Sparse matrices, Structured additive regression models

Structured additive regression models are perhaps the most commonly used class of models in statistical applications. It includes, among others, (generalized) linear models, (generalized) additive models, smoothing spline models, state space models, semiparametric regression, spatial and spatiotemporal models, log-Gaussian Cox processes and geostatistical and geoadditive models. We consider approximate Bayesian inference in a popular subset of structured additive regression models, latent Gaussian models, where the latent field is Gaussian, controlled by a few hyperparameters and with non-Gaussian response variables. The posterior marginals are not available in closed form owing to the non-Gaussian response variables. For such models, Markov chain Monte Carlo methods can be implemented, but they are not without problems, in terms of both convergence and computational time. In some practical applications, the extent of these problems is such that Markov chain Monte Carlo sampling is simply not an appropriate tool for routine analysis. We show that, by using an integrated nested Laplace approximation and its simplified version, we can directly compute very accurate approximations to the posterior marginals. The main benefit of these approximations is computational: where Markov chain Monte Carlo algorithms need hours or days to run, our approximations provide more precise estimates in seconds or minutes. Another advantage with our approach is its generality, which makes it possible to perform Bayesian analysis in an automatic, streamlined way, and to compute model comparison criteria and various predictive measures so that models can be compared and the model under study can be challenged Approximate Bayesian inference Gaussian Markov random fields Generalized additive mixed models Laplace approximation Parallel computing Sparse matrices Structured additive regression models

Are There Waves in Merger Activity After All?


International Journal of Industrial Organization

2009, vol. 27, n°6, pp.708-718

Départements : Marketing, GREGHEC (CNRS)

Back to the Origins of Positive Theories: A Contribution to an Analysis of Paradigm Changes in Accounting Research


Accounting in Europe

2009, vol. 6, n°1, pp.107-126

Départements : Comptabilité et Contrôle de Gestion

Mots clés : Research, Business education, Account books, Financial statements, Accountants, Management controls

In this article, we analyse factors that explain the success of the empirical methodology of ‘positive accounting theory’ (PA) in accounting research. In fewer than ten years, between 1960 and 1967–1968, PA became dominant in the main accounting journals, and normative theories disappeared from academic publishing. The reasons for this success are not clearly established. The propagators of PA (Ball and Brown, 1968; Watts and Zimmerman, 1986) advocate the fertility of their approach, while others (e.g. Mattessich, 1995; Mouck, 1988; Whittington, 1987; Williams, 1989) denounce their ostracism and systematic denigration of rival approaches. Both proponents and opponents of PA consider the emergence of positive theories as a radical severance; however, we suggest that the move from normative to positive theories occurred gradually. Even if they took advantage of the reform that took place in US business schools during the 1950s, the proponents of PA also benefited from a decoupling between the academic world and accounting practice initiated by their predecessors

Behavior in the loss domain: An experiment using the probability trade-off consistency condition


Journal of Economic Psychology

août 2009, vol. 30, n°4, pp.540-551

Départements : GREGHEC (CNRS)

Abstract: In gambles with two or more outcomes, the two versions of prospect theory, i.e., original prospect theory and cumulative prospect theory, make use of different composition rules and therefore yield different valuations of gambles. We test these composition rules in the loss domain using the probability trade-off consistency condition. The probability trade-off consistency condition offers a convenient and efficient way to compare gambles under risk and decision makers' behavior. Experimental findings suggest that the rank dependent version of prospect theory, or cumulative prospect theory, cannot be rejected in the loss domain while original prospect theory is clearly rejected when a certainty effect is taken into account.

Belief-free equilibria in games with incomplete information

J. Hörner, S. LOVO


mars 2009, vol. 77, n°2, pp.453-487

Départements : Finance, GREGHEC (CNRS)

We define belief-free equilibria in two-player games with incomplete information as se- quential equilibria for which players' continuation strategies are best-replies, after every history, independently of their beliefs about the state of nature. We characterize a setof payoffs that includes all belief-free equilibrium payoffs. Conversely, any payoff in the interior of this set is a belief-free equilibrium payoff.Keywords: repeated game with incomplete information; Harsanyi doctrine; belief-free equilibria.

Benchmarking the Impact of Customer Share in Key-Supplier Relationships

A. Eggert, W. ULAGA, S. Hollmann

Journal of Business and Industrial Marketing

2009, vol. 24, n°3/4, pp.154-160

Départements : Marketing

Mots clés : Relationship marketing, Buyer-seller relationships, Benchmarking

Purpose – Business marketers increasingly pursue greater shares of their customers' business. While the merits of such a strategy are straightforward from a supplier perspective, this paper aims to explore its consequences from the customer's point-of-view. Design/methodology/approach – Drawing on resource-dependence theory, value and dependence are established as fundamental characteristics of buyer-seller relationships. Data envelopment analysis is used as a benchmarking tool to integrate these characteristics into a common efficiency score indicating the customer-perceived attractiveness of a sourcing relationship. A post-DEA-regression-analysis explores the link between sourcing attractiveness and relative customer share. Findings – This research suggests a quadratic relationship between sourcing attractiveness and relative customer share. The perceived level of sourcing attractiveness improves until the local maximum is reached and declines beyond a relative customer share of 61.33 per cent. Research limitations/implications – Additional fraction of variability (R2) in sourcing attractiveness explained by customer share displays a modest, yet substantial, level. Studies on customer share in comparable contexts found similarly low levels. Practical implications – Sourcing attractiveness provides an interesting metric for assisting managers in their decision-making. Instead of comparing supplier relationships across the board, the proposed approach allows to compare relationships against their best-in-class benchmark. Findings suggest that the vast majority of supplier relationships still offers avenues for further improving the existing supply bases. Pushing the share of customer beyond its optimum level, however, will have negative consequences for the customer-perceived attractiveness of the sourcing relationship. Originality/value – The paper contributes to a better understanding of the consequences of customer share marketing from the customer's perspective.

Buying or selling a horse in France, an introduction to the legal context proposed to the attention of US equine lawyers


Kentucky Journal of Equine, Agriculture and Natural Resources Law

automne 2009, vol. 2, n°1

Départements : Droit et fiscalité

Capital Market Imperfections and the Sensitivity of Investment to Stock Prices


Journal of Financial and Quantitative Analysis

juin 2009, vol. 44, pp.551-578

Départements : Finance, GREGHEC (CNRS)