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Below you can find a list of publications that have come out of our research unit. 

Team Reasoning from an Evolutionary Perspective:
Categorization and Fitness

Leyla Ade & Oliver Roy

The question of the evolutionary stability of team reasoning has been answered in multiple, even opposing ways. We provide a general, conceptual categorization of these existing answers along four dimensions: (1) the unit of selection, (2) the notion of fitness for team reasoners, (3) the stage of decision-making, and (4) the ludic ecology. Beyond affording a better assessment of the different modeling choices underlying the existing results, the categorization highlights important conceptual questions for the evolutionary foundations of team reasoning. We illustrate this by looking in more detail into what should count as fitness for team reasoners.

Historical Social Research (2023)


International Organizations as Group Actors.
How Institutional Procedures Create Organizational Independence without Delegation to Institutional Agents

Thomas Gehring

Can international organizations (IOs) gain independence from their member states, even if their decisions arise from member state bodies? While organizational independence is a precondition for the autonomy and agency of IOs, International Relations theory cannot yet grasp IO independence in the absence of institutional agents like secretariats. Drawing on collective actor theories with a strong micro-foundation from philosophy and sociology, this article demonstrates how organizational rules and procedures gradually shape organizational processes and produce collective effects that do not arise from the aggregation of member state activities. Member-dominated IOs can produce collective beliefs about relevant parts of the outside world that differ from the aggregated beliefs of member states. They can comprise institutionalized organizational goals and criteria that indicate collective intentions of organizational action and differ from the aggregate preferences of member states. They can comprise decision-making procedures that foster organizational decisions according to collective beliefs and intentions and reduce or abolish the relevance of bargaining and preference aggregation. Finally, they can act in ways that do not immediately rely on implementation action by the member states or by other lower-level actors. I conclude that analyzing the sources of independence of member-dominated IOs from their members sheds light on the nature and effects of IOs as group actors.

Historical Social Research (2023)


Group Actors. Why Social Science Should Care About Collective Agency

Thomas Gehring & Johannes Marx


This paper examines conceptual issues of the emergence and effects of collective agency. Collective agency seems to challenge the methodological individualist assumption that only individuals can act, but treating group actors, such as parliamentary committees or court chambers, as mere shortcuts for complex interactions among group members raises important theoretical, empirical, and normative issues. First, the paper discusses some fundamental issues of collective agency. We argue that analyses of collective agency must provide generative mechanisms that demonstrate how it arises from the interaction of group members. Second, the paper introduces major approaches to collective agency from analytical philosophy and sociology. They locate the source of collective agency in the formation of collective intentions through the adjustment of group members' attitudes, in the organization of group decision processes, or in the transfer of resources to the group level, which empowers a collective actor to act in its own right. Against this backdrop, this paper offers an integrative concept of collective agency characterized in terms of the degree of autonomy and the level of resources controlled by a collective actor. Third, this paper introduces the contributions to this special issue, which tackle a broad variety of issues, including the formation and consequences of collective intentions in small and unorganized groups, collective agency issues of institutionalized groups and organizations, collective agency of large and unorganized groups without defined memberships, and normative issues of collective agency.

Historical Social Research (2022)

The Treaty Management Organization Established under the UNFCCC and the Paris Agreement: An International Actor in Its Own Right?

Thomas Gehring and Linda Spielmann

A peculiar treaty management organization operates under the UNFCCC and the Paris Agreement that does not fit established categories of international law and political science. Unlike traditional international organizations (IOs), it lacks the formal status of an IO, comprises only a limited secretariat with predominantly servicing functions, and is not even denominated as an organization. We argue that it has nevertheless become an international actor, mainly due to activities of its Conference of the Parties and several specialized organizational schemes. Theoretically, we develop an analytical framework that shows how even heavily member-dominated IOs can become international actors and what this means for global environmental governance. IOs gain the capability to influence international politics by their own action if authorized to make decisions with external effects. They gain autonomy if organizational rules and procedures shape organizational decision-making and create specific organizational rationales. Empirically, we demonstrate that the organizational component of the UNFCCC and the Paris Agreement has acquired both considerable action capability and autonomy. It is authorized to flesh out the skeletal provisions of the constituent treaties through far-reaching COP decisions and to decide continuously in several specialized organizational schemes, especially on climate funding, cooperation mechanisms, and compliance management. Organizational decisions are heavily influenced by autonomy-creating organizational factors, such as path dependence, fundamental organizational norms and dense sets of decision criteria. We conclude that this organization, and the organizational components of other multilateral environmental agreements, point at important organizational effects, which merit further attention.

International Environmental Agreements: Politics, Law and Economics (2022)


Simulation of Group Agency – From Collective Intentions to Proto-Collective Actors

Noichl, Maximilian, and Johannes Marx


This paper investigates the conditions under which cooperative team reasoning arises and stabilizes in complex social structures. Team reasoning is a theory that explains cooperative behavior in social settings of strategic choice, even in situations where classical game theory fails. By simulating the emergence of cooperation via team reasoning, this paper analyzes the performance of team reasoners compared to classically rational agents and individual reasoners. Simulation results are provided regarding the efficacy of team reasoning in mixed-game settings. It is shown that cooperative team reasoning is viable and stabilizing under favorable conditions such as the share of coordination games played, but sensitive to the amount and abilities of their interacting counterparts. Finally, the paper provides first ideas on how the current framework might be extended toward collective actors that gain further stability through processes of self-formalization and inner-organizational redistribution.

Historical Social Research (2023)

Member-dominated international organizations
as actors: a bottom-up theory of
corporate agency

Thomas Gehring & Kevin Urbanski

This article introduces an innovative theoretical conception of the corporate agency of international organizations (IOs). Existing rationalist and constructivist accounts attribute IO agency to the influence of intra-organizational agents. Drawing on general conceptions of corporate agency in International Relations, sociology, and philosophy, we elucidate how IOs can develop corporate agency, even if the member states prepare and adopt all organizational decisions themselves. In line with recent studies on international political authority, we replace the IO-as-bureaucracy model with the more comprehensive concept of IOs-as-governors. To establish the micro-foundations of IO agency, we adopt a bottom-up perspective and outline how, and under which conditions, IO agency arises from the interaction of constituent actors. Irrespective of any specific institutional design, IOs become actors in their own right whenever they gain action capability and autonomy. They acquire action capability whenever their members pool governance resources like the right to regulate certain activities or to manage common funds and authorize IOs to deploy these resources. IOs gain autonomy whenever they affect organizational decisions. Both dimensions of IO agency are variable and open to empirical enquiry. To illustrate our argument, we refer to the United Nations Security Council and other IOs with member-driven decision processes.

International Theory (2022)


Rational Choice Explanations in Political Science

Catherine Herfeld & Johannes Marx

In this paper, Herfeld & Marx describe and assess how political scientists use rational choice theories to offer causal explanations. We observe that the ways in which rational choice theories are considered to be successful in political science differ, depending on the explanandum in question. Political scientists use empirical variants of rational choice theories to explain the political behavior of individual agents and analytical variants to explain the behavior of collective actors. Both variants are used for distinct explananda, which ask for different modes of explanation that raise in turn different explanatory demands towards rational choice theories. We argue that when political scientists discuss the explanatory usefulness of rational choice theories, they should assess them in light of the demands they are supposed to meet. This would enable a more nuanced and problem-oriented appraisal of rational choice theories in political science.


Accepted for publication in the Oxford Handbook of Philosophy of Political Science

Read the Paper (coming soon...)

Deliberation, Single-Peakedness, and Coherent Aggregation

Soroush Rad & Olivier Roy

Rational deliberation helps to avoid cyclic or intransitive group preferences by fostering meta-agreements, which in turn ensures single-peaked profiles. This is the received view, but this paper argues that it should be qualified. On one hand we provide evidence from computational simulations that rational deliberation tends to increase proximity to so-called single-plateaued preferences. This evidence is important to the extent that, as we argue, the idea that rational deliberation fosters the creation of meta-agreement and, in turn, single-peaked profiles does not carry over to single-plateaued ones, and the latter but not the former makes coherent aggregation possible when the participants are allowed to express indifference between options. On the other hand, however, our computational results show, against the received view, that when the participants are strongly biased towards their own opinions, rational deliberation tends to create irrational group preferences, instead of eliminating them. These results are independent of whether the participants reach meta-agreements in the process, and as such they highlight the importance of rational preference change and biases towards one’s own opinion in understanding the effects of rational deliberation.

Legislative Organization, Electoral Vulnerability and Constituency Focus in the British House of Commons and the German Bundestag

David Beck & Thomas Saalfeld

In this paper, which reflects work in progress both empirically and conceptually, we examine the extent to which British and German legislators use questions for written answer to voice concerns relating to their electoral districts. We find considerable variations in the use of written questions across the two chambers collectively, among the members of each chamber and across individual legislators’ career trajectories. Our focus is the extent to which the number of written questions relating to electoral districts varies across legislators’ parliamentary careers. We are investigating, for example, whether the distribution of written questions across legislators’ careers reflects a declining interest in local matters and an increasing focus on national policies as they adapt to the rules of the legislative game and reduce their initial electoral vulnerability. We compare data from two parliaments because we seek to explore the behavioral implications of trends that some political sociologists have considered to be almost universal in established liberal democracies, namely the professionalization of political elites and their growing independence from their democratic principals among voters and party activists. While we cannot derive any generalizations from the study of MPs in two parliaments, we are able to reduce the risk of overgeneralization. At the same time, the binational comparison still allows the development of sufficiently sensitive validation strategies for the automated content analysis of the texts of parliamentary questions. Using multi-variate panel regressions for three legislative periods between 2001 and 2015 in the UK and two periods between 2002 and 2009 in Germany, we do not find any significant decline of the number of parliamentary questions with a constituency focus across legislative careers in either of the chambers. Based on data for the UK, we find that electoral vulnerability is a strong, consistent and significant predictor that also moderates the effect of parliamentary experience.

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