Experiments in the Social Sciences: The relationship between External and Internal Validity

The article identifies a latent debate in the recent literature on the role and worth of experiments in economics and other social sciences concerning the relationship between the external and the internal validity of experimental designs. Our work identifies two incompatible views regarding the relationship between internal and external validity of experiments. While in the methodological literature references to the idea that there is a trade-off between the internal and external validity of experiments abound, this view coexists with the position stating that internal validity is rather a prerequisite of external validity. By identifying the contours of this implicit debate in the recent methodological literature around the use of experiments in the social sciences we call attention upon a series of insufficiently conceptualized issues regarding the central notions of internal and external validity and we question the standard view positing a trade-off between the two. This article stands against common associations of internal validity and external validity with the distinction between field and laboratory experiments and assesses critically the arguments that link the artificiality of experimental settings done in the laboratory with the purported trade-off between internal and external validity

Reactivity in Social Scientific experiments: What is it and how is it different (and worse) than a Placebo effect?

Reactivity, or the phenomenon by which subjects tend to modify their behavior in virtue of their being studied upon, is often cited as one of the most important difficulties involved in social scientific experiments, and yet, there is to date a persistent conceptual muddle when dealing with the many dimensions of reactivity. This paper offers a conceptual framework for reactivity that draws on an interventionist approach to causality. The framework allows us to offer an unambiguous definition of reactivity and distinguishes it from placebo effects. Further, it allows us to distinguish between benign and malignant forms of the phenomenon, depending on whether reactivity constitutes a danger to the validity of the causal inferences drawn from experimental data

The trade-off between efficiency and equality : the role of an economic idea in the political strategy of social democratic parties

Defence date: 13 June 2005Examining board: Prof. José María Maravall (CEACS, Juan March Institute) ; Prof. Adam Przeworski (NYU)(External Co-Supervisor) ; Prof. Martin Rhodes (EUI)(Supervisor) ; Prof. Peter Wagner (EUI)PDF of thesis uploaded from the Library digitised archive of EUI PhD theses completed between 2013 and 201

The trade-off between efficiency and equality : the role of a changing economic idea in the political strategy of the social democracy

Digitised version produced by the EUI Library and made available online in 2020