Rosa Borge, Open University of Catalunya (UOC)
One of the main problems in studies of political participation based on cross-sectional survey data is the question of causality. It is difficult to discern with certainty the impact on participation of key explanatory factors such as political mobilization, information, knowledge and political interest, political efficacy or, lately, the use of Internet. Several methodological problems have hindered sound causal inferences: confounding factors affecting both Internet use and participation, omitted variables, the impossibility of establishing a before-and-after sequence, self-selection of politically active citizens into Internet use, and reverse causality.
Two currently popular methods for properly examining the causal direction and effect of Internet usages are to use panel surveys or carry out experiments. By following these two methods it is possible to verify the effect of the explanatory variables before and after they take place, while the rest of the variables and self-selection processes are being controlled. We will review some of the most important studies that have analysed the effect of the Internet on participation using panel data and experiments. Their findings complement and nuance those of cross-sectional studies, and sometimes serve to arbitrate between conflicting results from cross-sectional data. However, in order to contribute to the accumulation of knowledge in the study of the role of the Internet in participation, they should pay attention to the problems found in cross-sectional studies and aim to form part of a body of related studies. Although most of the studies examined here clearly did, the extraordinary rise in experimental studies is bringing about very specific results difficult to extrapolate and compare with cross-sectional results.