Stefan Napel

The Inter-Institutional Distribution of Power in EU Codecision

This paper analyzes the a priori influence of the European Parliament (EP) and the Council of Ministers (CM) on legislation of the European Union adopted under its codecision procedure. In contrast to studies which use conventional power indices, both institutions are assumed to act strategically. Predicted bargaining outcomes of the crucial Conciliation stage of codecision are shown to be strongly biased towards the legislative status quo. Making symmetric preference assumptions for members of CM and EP, CM is on an average much more conservative because of its internal qualified majority rule. This makes CM by an order of magnitude more influential than EP, in contrast to a seeming formal parity between the two ‘co-legislators’.

Power Measurement as Sensitivity Analysis - A Unified Approach ⁄

This paper proposes a unified framework that integrates the traditional index-based approach and the competing non-cooperative approach to power analysis. It rests on a quantifiable notion of ex post power as the (counter-factual) sensitivity of the expected or observed outcome to individual players. Thus, it formalizes players’ marginal impact on outcomes in both cooperative and non-cooperative games, for both strategic interaction as well as purely random behavior. By taking expectations with respect to preferences, actions, and procedures, one obtains meaningful measures of ex ante power. Established power indices turn out to be special cases.

Equal representation in two-tier voting systems

The paper investigates how voting weights should be assigned to differently sized constituencies of an assembly. The one-person, one-vote principle is interpreted as calling for a priori equal indirect influence on decisions. The latter are elements of a one-dimensional convex policy space and may result from strategic behavior consistent with the median voter theorem. Numerous artificial constituency configurations, the EU and the US are investigated by Monte–Carlo simulations. Penrose’s square root rule, which originally applies to preference-free dichotomous decision environments and holds only under very specific conditions, comes close to ensuring equal representation. It is thus more robust than previously suggested.

Intergenerational Mobility and Macroeconomic History Dependence

That historical inequality can affect long run macroeconomic performance has been argued by a large literature on ‘endogenous inequality’ using models of indivisibilities in occupational choice, in the presence of borrowing constraints. These models are characterized by a continuum of steady states, and absence of mobility in any steady state. We augment such a model with heterogeneity in agents’ abilities in order to generate occupational mobility in steady state. Steady states with mobility are shown to be generically locally unique and finite in number. We provide forms of heterogeneity for which steady state is globally unique, and others where they are non-unique. Agent heterogeneity may also cause competitive equilibrium dynamics to fail to converge, but convergence can be restored in the presence of sufficient ‘inertia’ or occupation switching costs.

The Possibility of a Preference-Based Power Index

This article replies to the claim that preference-based power indices are impossible and that preferences should be ignored when assessing actors’ influence in different interactions (Braham and Holler [2005] ‘The Impossibility of a Preference-based Power Index’, Journal of Theoretical Politics 17: 137-57). The article argues that preferences are an important determinant of potential and actual outcomes of social interaction and thereby a valuable ingredient of power analysis.

Inferior players in simple games

Abstract. Power indices like those of Shapley and Shubik (1954) or Banzhaf (1965) measure the distribution of power in simple games. This paper points at a deficiency shared by all established indices: players who are inferior in the sense of having to accept (almost) no share of the spoils in return for being part of a winning coalition are assigned substantial amounts of power. A strengthened version of the dummy axiom based on a formalized notion of inferior players is a possible remedy. The axiom is illustrated first in a deterministic and then a probabilistic setting. With three axioms from the Banzhaf index, it uniquely characterizes the Strict Power Index (SPI). The SPI is shown to be a special instance of a more general family of power indices based on the inferior player axiom.

Aspiration adaptation in the ultimatum minigame

Abstract Two agents recurrently play a 2×2 version of the ultimatum game. Each player sticks to his past action if it was satisfactory relative to an endogenous aspiration level and otherwise abandons it with positive probability. This type of satisficing behavior is shown to yield efficiency in the limit. It does not favor a specific distribution of surplus and can give an explanation for the incidence of equitable offers in practice. Numerical investigations link a players character as captured by the model parameters to his average bargaining success. Results indicate that it is beneficial to be persistent and stubborn, i.e., slow in adapting aspirations and switching actions in response to major dissatisfaction. Also, it is an advantage to be capricious, i.e., to experience large and frequent perturbations of aspiration level and to discriminate only little between minor and major dissatisfaction.

The Power of a Spatially Inferior Player

Traditional power indices are not suited to take account of explicit preferences, strategic interaction, and particular decision procedures. This paper studies a new way to measure decision power, based on fully specified spatial preferences and strategic interaction in an explicit voting game with agenda setting. We extend the notion of inferior players to this context, and introduce a power index which - like the traditional ones - defines powers as the ability to have pivotal influence on outcomes, not as the (often just lucky) occurrence of outcomes close to a players ideal policy. Though, at the present state, formal analysis is based on restrictive assumptions, our general approach opens an avenue for a new type of power measurement

Strategic versus non-strategic voting power in the EU Council of Ministers: the consultation procedure

This article evaluates the distribution of power within the Council of the European Union from the a priori perspective of constitutional design using two distinct approaches: (1) applying traditional voting power indices; (2) carrying out strategic equilibrium analysis of the EU’s consultation procedure. It clarifies why both approaches lead to different power indications, and investigates the determinants of the differences’ magnitudes. Depending on one’s assumptions about behavior of the consultation procedure’s agenda setter, the European Commission, traditional indices turn out to deliver a good approximation also of relative strategic power in the Council.

On the Democratic Weights of Nations

Which voting weights ought to be allocated to single delegates of differently sized groups from a democratic fairness perspective? We operationalize the one person, one vote principle by demanding every individual’s influence on collective decisions to be equal a priori. The analysis differs from previous ones by considering intervals of alternatives. New reasons lead to an old conclusion: weights should be proportional to the square root of constituency sizes if voter preferences are independent and identically distributed. This finding is fragile, however, in that preference polarization along constituency lines quickly calls for plain proportionality.