GDN 2012 | An International Meeting on Group Decision and Negotiation
Recife, Brazil, 20 - 24 May, 2012
Keynote Speakers
Gregory E. Kersten
Concordia University, Canada
To bid or to bargain? Comparisons of multi-attribute auctions and multi-bilateral negotiations
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Gregory E. Kersten is a professor of decision and negotiation systems and Senior Concordia Research Chair at the John Molson School of Business, Concordia University. He is also an adjunct research professor at the Carleton University Sprott School of Business. His research and teaching interests include individual and group decision-making, negotiation analysis, knowledge-based systems and knowledge management, decision and negotiation support, web-based system development and electronic commerce. He was a founding member and the first Director of the Decision Analysis Lab (DAL), Carleton University Sprott School of Business, the first Director of the Information Systems and the CIT at the John Molson School of Business, Concordia University, a member of the Ottawa-Carleton Institute for Computer Science, and the Director of the E-negotiation, media and transaction research program (2002-07). In 1996 he set up the InterNeg Group involved in on-line training and development of e-negotiation systems. In 2005 this virtual organization became the InterNeg Research Centre at Concordia University of which he is the Director. He is a vice-chairperson of the INFORMS Group Decision and Negotiation Section, senior and a departmental editor of the Group Decision and Negotiation Journal. In 2006 he received the GDN Award.

To bid or to bargain? Comparisons of multi-attribute auctions and multi-bilateral negotiations

The apparent superiority of auctions over negotiations can be easily refuted if the definition of negotiation follows those used in sociology and management. One possibility is to allow the parties to discuss, propose side deals, make commitments, threats, or add issues. This would allow at least one side to achieve more than they would have achieved if they were allowed to make only bids. There are also other reasons for the persistence of negotiation mechanisms in the marketplace. The inability for the full specification of the entity (product or service) prior to the exchange that requires the parties discuss some of its aspects during the process. The need to consider the entity’s many attributes, which cannot be reduced to price, requires exchange of information on all the relevant attributes, rather than price only. Differences among the participating parties in terms of their reputation, trustworthiness, operational flexibility, and ability to use new technologies need to be considered when their offers are evaluated.
Comparison of auctions and negotiations can be done on formal and experimental bases; both are presented. Earlier comparisons focused on single-attribute processes. In this talk multi-attribute (multi-issue) auctions and negotiations are presented and compared. Auctions are based on a novel procedure which does not require attribute measurement and aggregation, for example, into a utility. This allows bids with the same format as offers in negotiations. The auction procedure does not require an exchange of preferences making it similar to negotiation process. It does provide, however, an automated feedback regarding the progress of the process. This feedback is similar to the “negotiation in good faith” rule which includes the requirement that the negotiators cannot make an offer that is worse for their counterparts than the offer they made earlier. The negotiation procedure mirrors the auction with an addition of offers and messages that both sides can exchange.
We have implemented both procedures in the Invite platform. The platform’s design and architecture allows designing systems that implement different protocols but have very similar interfaces. Multi-attribute auction system (Imaras) and multi-bilateral negotiation system (Imbins) are briefly mentioned and their use discussed. These systems have been used in several lab and online experiments. The experimental settings and results are also discussed.
The talk concludes with recommendations regarding the design and use of auctions and negotiations exchange mechanisms. Some answers to the “bid or bargain” question are also given.

Hannu Nurmi
University of Turku, Finland
Voting Rules in Context
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Hannu Nurmi is the professor of political science and director of the Centre of Public Choice Research at University of Turku, Finland. From 1991 till 1996 he was the dean of faculty of social sciences in University of Turku. From 2003 till 2008 he was an Academy Professor of Academy of Finland. He has worked in the United States as a Senior Fulbright Fellow at Johns Hopkins University and as a Visiting Professor at University of Minnesota. In United Kingdom he has been a British Academy Wolfson Fellow at University of Essex. He is the author or co-author of about 200 scholarly articles and ten books. He serves on the editorial board of ten scholarly journals and, together with Manfred J. Holler, edits a book series Politics, Philosophy and Economics for Oldenbourg publishing house. Nurmi is a member of the Finnish Academy of Sciences and Letters.

Voting Rules in Context

The fi rst thing to be said about voting rules is that they come in a wide variety of forms. This raises the question about their underlying motivations: what are they supposed to do and do they actually reach their goals? We briefly discuss the most common voting rules and review their most important properties. We also outline a characterization of voting rules in terms of a specifi c goal (desired consensus) state and a distance measure so that each rule can be seen as minimizing the distance between the observed opinions and the goal state (using the distance measure as a yardstick).
Even a cursory glance at voting rules reveals that somewhat different rules are devised for diff erent contexts. In the best-known ones individuals are elected to offices. In these settings the alternative set along with voter opinions are usually exogenously given and the question addressed by the choice theory is what kinds of desiderata can be imposed on choices of candidates and to what extent various rules satisfy those desiderata. A rich literature exists on these issues. Our special focus is on how relevant are the theoretical results in guiding the choice of voting rule.
However, equally important as the candidate choices are settings where policy choices are at issue. In these a new factor, agenda, enters the scene. Two common agenda rules - the amendment and successive systems - split the policy alternative set into basically binary choices thereby vesting the agenda-setter with considerable influence over the outcomes.
The third type of setting involves aggregation of expert judgments taking explicitly into account di erent levels of expertise of the decision makers. This research focus has its origin in Condorcet's jury theorem and has over the past decades spanned a literature that will also be briefly reviewed.

Keith W. Hipel
University of Waterloo, Canada
Strategic investigations of water conflicts in the Middle East
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Keith W. Hipel is University Professor of Systems Design Engineering and Coordinator of the Conflict Analysis Group at the University of Waterloo in Canada. He is Senior Fellow at the Centre for International Governance Innovation and former Vice President of the Canadian Academy of Sciences. His major research interests are the development of conflict resolution, multiple objective decision making and time series analysis techniques from a systems thinking perspective with applications in water resources management, hydrology, environmental engineering and sustainable development. Dr. Hipel has received widespread recognition for his interdisciplinary research in systems engineering via Fellow designations from IEEE, Royal Society of Canada, International Council on Systems Engineering, Canadian Academy of Engineering, Engineering Institute of Canada, and American Water Resources Association. He is the recipient of the Norbert Wiener Award from the IEEE Systems, Man, and Cybernetics Society and Docteur Honoris Causa from École Centrale de Lille in France.

Strategic investigations of water conflicts in the Middle East

The great import of methodologies from group decision and negotiation, and the Graph Model for Conflict Resolution in particular, for resolving a wide variety of conflicts is put into perspective by this study involving the use of the Graph Model to systematically investigate conflicts over water in the Middle East. Because of the relative scarcity of fresh water at many locations around the globe, widespread pollution of water by industrial and agricultural activities, and disruption of the hydrological cycle via climate change and land-use alterations, conflicts over the quality and fair distribution of water resources are increasing in number and intensity, both within and among nations. Indeed, neighboring countries’ relations over water can range from highly cooperative to explicitly hostile, up to and including war. Following an overview of the types of water conflicts and formal techniques for addressing them, strategic analyses are executed using the Graph Model for three connected water conflicts that occurred along the Euphrates River in 1975, 1990, and 1998. The goal is to gain strategic insight into the causes and eventual resolutions of these disputes, and to learn how similar situations can be effectively managed in the future. The three conflicts involve Turkey, the upstream country of both the Euphrates and Tigris Rivers, and one or both of Syria and Iraq, which lie downstream. The analyses demonstrate the importance to conflict resolution of coalitions and third-party interventions.

Pascale Zaraté
Toulouse Polytechnique Institute - IRIT, France
Cooperative Decision Support Systems
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Pascale Zaraté is a Professor at Toulouse 1 Capitole University. She conducts her researches at the IRIT laboratory ( She holds a Ph.D. in Computer Sciences / Decision Support from the LAMSADE laboratory at the Paris Dauphine University, Paris (1991). She also holds a Master degree in Computer Science from the Paul Sabatier University, Toulouse, France (1986); as well as a Bachelors degree Toulouse, France (1982). Pascale Zaraté’s current research interests include: Decision Support Systems; distributed and asynchronous decision making processes; knowledge modelisation; cooperative knowledge based systems; cooperative decision making. She is the editor in chief of the International Journal of Decision Support Systems Technologies (Ed IGI Global). Since 2000, she is head of the Euro Working Group on DSS (
She published several studies and works 1 book, edited 2 books, edited 11 special issues in several international journals, 2 proceedings of international conferences, 22 papers in several international journals, 2 papers in national journals, 5 chapters in collective books, 26 papers in international conferences.

Cooperative Decision Support Systems

Decision Support Systems are designed in order to support decision makers in organisations. This support is strictly linked to an improvement of the efficiency of the made decisions rather than the effectiveness. The decision making process is then seen as an interaction between the man and the machine and the automation of this kind of process is not feasible. We show in this work how the introduction of Information and Communication Technologies (ICT) changed the decision making processes in organisations. The decisional context evolves from a mono decision maker to multi decision makers, each of them having to interact and to cooperate with the others. Based on this hypothesis we studied this new decision making processes: multi actors working in asynchronous and distributed situations. These processes are then defined as cooperative. We then show how the Decision Support Systems are not adapted to these new needs and we make the proposal of a new kind of framework called Cooperative Decision Support Systems able to support these processes of decision making. This framework is based on the proposed architecture by Sprague and Carlsson.

Rudolf Vetschera
University of Vienna, Austria
Beyond phase models: Innovative methods to analyze negotiation dynamics
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Rudolf Vetschera is a professor of organization and planning at the faculty of Business, Economics and Statistics, University of Vienna, Austria. He holds a PhD in economics and social sciences from the University of Vienna, Austria. Before his current position, he was full professor of Business Administration at the University of Konstanz, Germany. He has published three books and more than ninety papers in reviewed journals and collective volumes . His main research area is in the intersection of organization, decision theory, and information systems, in particular electronic negotiations, decisions under incomplete information, and the impact of information technology on decision making and organizations.

Beyond phase models: Innovative methods to analyze negotiation dynamics

Hardly any empirical paper on negotiations published during the last decade failed to point out the importance of developing a thorough understanding of the inherent dynamics of negotiation processes – and most of these papers also deferred this topic to future research. However, there has also been considerable progress in this field during the last years.
One important contribution to our understanding of negotiation processes was the development of phase models of negotiations, which already began in the 1990ies. Phase models typically focus on the communication content exchanged during different parts of a negotiation, and identify changes in the use of different tactics and strategies over time. They mainly operate on qualitative data, which refers to the relationship building aspect of negotiation processes.
In this survey, we will focus on methods which take a more quantitative approach to analyzing negotiation processes. Most of the methods we discuss deal with substantive aspects of the negotiation process, in particular the offers that are exchanged and concessions being made by the parties. Following the classification by Koeszegi and Vetschera (2010), we consider methods at the macro level of entire negotiations, the meso level of parts of negotiations, and the micro level of single interactions.
At the macro level, we will discuss methods based on grammar complexity, which provide a compact representation of the structuredness of negotiation dynamics. Grammar-based methods allow to identify and analyze sequences and patterns of actions/interactions by negotiators.
At the meso level, we present the use of standardized interpolated negotiation paths. This approach considers the offer process in utility space, and allows for the aggregation and comparison of concession patterns across multiple negotiations.
At the micro level, we will discuss the Actor-Partner Interdependence Model. This model provides a powerful statistical estimation method, which models the interaction process between interdependent actors (like the parties in a negotiation process), and allows to deal with the estimation problems that can arise from the independence of observations.
We will illustrate the application of these methods, and the results that can be obtained by applying them, with data from a recent set of negotiation experiments in which we studied the impact of different support techniques on the processes of electronic negotiations.

Plenary Panel GDN: Historical background and future developments
Melvin Shakun, New York University, USA (Keynote Bio)
Marc Kilgour, Wilfrid Laurier University, Canada (Keynote Bio)
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Melvin F. Shakun is Professor Emeritus of Operations Research and Statistics, Leonard N. Stern School of Business, New York University. He is Editor-in-Chief of Group Decision and Negotiation, an international journal he founded in 1992 published by Springer publishers in cooperation with the Institute for Operations Research and the Management Sciences (INFORMS) and its Section on Group Decision and Negotiation (GDN). He is also Editor of the Springer book series, Advances in Group Decision and Negotiation.Professor Shakun is Chair of the INFORMS Section on GDN and a General Chair of the international annual meeting of the Section. He has broad experience in management consulting. Current research includes the Connectedness Paradigm, CATNAPS -- Connectedness And Technology for Negotiation And Problem Solving, Connectedness Capitalism, Humans and Computer Agents in Negotiation, Leadership and GDN.

D. Marc Kilgour is Professor of Mathematics at Wilfrid Laurier University in Waterloo, Canada, Research Director: Conflict Analysis of the Laurier Centre for Military Strategic and Disarmament Studies, and Adjunct Professor of Systems Design Engineering at University of Waterloo. His research lies at the intersection of mathematics, engineering, and social science, and he has addressed problems in international security, arms control, environmental management, negotiation, arbitration, voting, fair division, elections, social choice, and coalition formation. He pioneered the development of decision support systems for strategic conflict and their application to negotiation support. His research and lifetime contributions have earned many international awards and distinctions. With Colin Eden, he co-edited the Handbook of Group Decision and Negotiation, which was officially launched at GDN 2010. He is believed to be the only person to have attended all twelve of the GDN series conferences.

Plenary Panel GDN: Historical background and future developments

The growing field of Group Decision and Negotiation has been called “the empirical, formal, computational, and strategic analysis of group decision-making and negotiation, especially from the viewpoints of Management Science and Operations Research.” Supported by the sequence of GDN conferences, the journal Group Decision and Negotiation, and the recently-published Handbook of Group Decision and Negotiation, the field has advanced across a broad front, and now includes essential contributions from many disciplines including business administration, business strategy, systems engineering, computer science, mathematics, and law, as well as economics, psychology, and other social sciences.
This panel will relate the multi-faceted history of Group Decision and Negotiation to current and emerging problems and issues. The fundamental principles for negotiation and group decision-making remain valid, and can still be seen in current practice, as well as in the trends in support systems for these activities, and in the accelerating development of on-line or computer-based arbitration and negotiation systems. The continuing relevance and recent transformation of issues such as knowledge, language, strategy, framing, fairness and justice will also be emphasized. Group Decision and Negotiation is a thriving interdisciplinary field, in which researchers share the common focus of negotiation and collaboration as complex multi-participant, multi-criteria, ill-structured, dynamic, and often evolutionary processes.