Le processus de décision dans les systèmes complexes : une analyse d’une intervention systémique

The objective of this thesis is to contribute to a better understanding of decision processes in a complex system, by analysing how systemic interventions produce changes in the decision-making process followed by individuals. More precisely, this research analyses the potential effects of the use of a systemic model by decision-makers, on both the constitutive activities and the dimensions of decision processes, while taking into consideration their potential determinants. The research involves an experiment based on one simulated case about the intellectual property system of biotechnological innovations: experimental sessions consist in individual interviews with policy-makers, and the systemic intervention concerns the use of a simulation model based on the system dynamics approach. The results suggest: 1) a multiple, cumulative, conjunctive, and iterative progression; 2) an incremental, based on multiple perspectives, and creative decision-making procedure; 3) the multiplicity of involved actors, with diversified interests and roles; 4) rationalities which are political, limited, contextual, and even socio-cognitive. Moreover, the results show that decision-makers, who benefit from a systemic intervention, tend to consider more analytical elements and scientific disciplines during their decision analysis, and to involve additional internal and external actors.