This paper (which is mainly expository) sets up graphical models for causation, having a bit less than the usual complement of hypothetical counterfactuals. Assuming the invariance of error distributions may be essential for causal inference, but the errors themselves need not be invariant. Graphs can be interpreted using conditional distributions, so that we can better address connections between the mathematical framework and causality in the world. The identification problem is posed in terms of conditionals. As will be seen, causal relationships cannot be inferred from a data set by running regressions unless there is substantial prior knowledge about the mechanisms that generated the data. There are few successful applications of graphical models, mainly because few causal pathways can be excluded on a priori grounds. The invariance conditions themselves remain to be assessed.

Experiments offer more reliable evidence on causation than observational studies, which is not to gainsay the contribution to knowledge from observation. Experiments should be analyzed as experiments, not as observational studies. A simple comparison of rates might be just the right tool, with little value added by “sophisticated” models. This article discusses current models for causation, as applied to experimental and observational data. The intention-to-treat principle and the effect of treatment on the treated will also be discussed. Flaws in per-protocol and treatment-received estimates will be demonstrated.

populism, and social policy in Latin America. He has also edited Learning from Foreign Models

Abstract 1 Deregulation through temporary employment has generated important inequalities in the Spanish labour market. The paper presents a theoretical model as well as empirical evidence to explain this process. The main thrust of the model is seeing labour market structures as always being the result of micro-level strategies of employers and employees over employment rents. The employment-rent approach defended in the paper focuses on the impact of deregulation through temporary employment on the employment-rent optimisation strategies of both employers and employees at the micro-level. Drawing on recent developments in labour economics, the paper identifies two main micro-level effects of deregulation, the so-called ‘incentive ’ and ‘buffer ’ mechanisms. These two mechanisms are expected to reinforce each other until an equilibrium state in the segmentation process is reached. The employment-rent model is tested using data from the Spanish Labour Force Survey for the period 1987-97, as well as data on wages drawn from the Survey on Class Structure, Class Consciousness and Class Biography (1991). The evidence proves consistent with the predictions of the model. The Spanish experience illustrates the extent to which institutional (de)regulation can have a crucial impact on labour market structures in contemporary capitalism.

The economic approach to human behaviour under scrutiny: an overview of arguments for the autonomy of social action Abstract. The article reviews and re-examines some arguments against the treatment of social action within the economic approach as an extension of economic behaviour/ rationality and thus against its denial of the speci®c, irreducible nature of the extra-economic. A major argument is that social action is a sui generis phenomenon that cannot be reduced with theoretical impunity to its economic modalities. Social action is characterized by substantial autonomy relative to economic behaviour/ rationality. Arguments about the autonomous character of social action seek to remedy the indiscriminate extension of the economic approach beyond the ®eld of economy to all human behaviour construed as consistent utility maximization. These arguments adduce certain classes of factors (socio-psychological, socio-cultural, socio-systemic and others) contributing toward the autonomy of social action. In addition, the economic-approach treatment of the human actor as Homo economicus is reversed by conceiving the economy as a domain of social action of which economic behaviour is a special case. Key words. Autonomy ± Economic rationality ± Social action This article scrutinizes the economic (or rational action) approach to social action (for recent advocacy and overviews in sociology, see

Critical realism has emerged as an alternative to positivist and interpretive research during the past decade. Yet, the number of empirical studies based on this perspective has so far been limited. This indicates a need for a more explicit method for critical realist data analysis. To address this, we extend former research on critical realist methodology by presenting a framework for identifying and understanding causal structures in critical realist studies, termed mechanisms. The framework consists of steps involved in identifying structural components of a mechanism, how these components interact to produce to an outcome, and contextual influences on this outcome. We illustrate the application of the framework through an example of the identification of IS innovation mechanisms in a case study in the airline industry. Overall, we argue that the mechanism approach can improve empirical studies in the IS field, by providing ontological depth, creative thinking and more precise explanations.

This paper contributes to the debate on the virtues and vices of counterfactuals as a basis for causal inference. The goal is to put the counterfactual approach in an epistemological perspective. We discuss a number of issues, ranging from its non-observable basis to the parallelisms drawn between the counterfactual approach in statistics and in philosophy. We argue that the question is not to oppose or to endorse the counterfactual approach as a matter of principle, but to decide what modelling framework is best to adopt depending on the research context.