How do food safety regulations influence market price? A theoretical analysis

Purpose This study is in line with the debate concerning the compatibility between the qualitative and quantitative food production objectives. The purpose of this paper is to identify the causal relationship that may exist between public food safety regulations (specifically, the maximum authorised levels of chemical or microbiological contaminants), and the expected price in the spot markets (wholesale markets, for example). Design/methodology/approach The authors propose a theoretical industrial economic model that identifies the causal link which may exist between public food safety regulations (e.g. the maximum authorised levels of chemical or microbiological contaminants), the expected price in domestic markets, and the rate of exclusion of local producers. This general model allows one to characterize the price formation process in markets subject to maximum residue level constraints by focusing on the role of the official inspection systems established by public authorities. Findings The authors show how strengthening official controls does not systematically impact negatively on producers’ participation and does not always decrease supply. Moreover, the authors show that reinforcing the maximum permitted contamination thresholds is not always sufficient for ensuring consumer health. Originality/value The originality of the model is that it shows how all variables (economic and sanitary variables) interact in the formation of agricultural prices and determine the final size of the productive system (number of active producers). The characterisation of the market price as a function of producers’ investment efforts and of the level of official control reliability allows one to determine both the total supply and the proportion of this supply that is contaminated (i.e. does not comply with the maximum threshold of contamination)

Lower total cost for the Two-Variable Sized Bin-Packing Problem

International audienc

Weak Pseudo-Invexity and Characterizations of Solutions in Multiobjective Programming

In this paper, we study Fritz John type optimality for nonlinear multiobjective programming problems under new classes of generalized invex vector functions. Relationships between these classes of vector functions are established by giving several examples. Furthermore, optimality conditions and characterizations of efficient and weakly efficient solutions are obtained under weak pseudoinvexity and by using a concept of generalized Fritz John vector critical point. We have illustrated through various non-trivial examples that the results obtained in this paper extend many previously known results in this area

Fritz John type optimality and duality in nonlinear programming under weak pseudo-invexity

In this paper, we use a generalized Fritz John condition to derive optimality conditions and duality results for a nonlinear programming with inequality constraints, under weak invexity with respect to different (ηi)i assumption. The equivalence between saddle points and optima, and a characterization of optimal solutions are established under suitable generalized invexity requirements. Moreover, we prove weak, strong, converse and strict duality results for a Mond-Weir type dual. It is shown in this study, with examples, that the introduced generalized Fritz John condition combining with the invexity with respect to different (ηi)i are especially easy in application and useful in the sense of sufficient optimality conditions and of characterization of solutions

Nondifferentiable multiobjective programming under generalized dI-invexity

In this paper, we are concerned with a nondifferentiable multiobjective programming problem with inequality constraints. We introduce new concepts of dI-invexity and generalized dI-invexity in which each component of the objective and constraint functions is directionally differentiable in its own direction di. New Fritz-John type necessary and Karush-Kuhn-Tucker type necessary and sufficient optimality conditions are obtained for a feasible point to be weakly efficient, efficient or properly efficient. Moreover, we prove weak, strong, converse and strict duality results for a Mond-Weir type dual under various types of generalized dI-invexity assumptions.Multiobjective programming Semi-directionally differentiable functions Generalized dI-invexity Optimality Duality (Weakly or properly) efficient point