Abstract
Recent proposals for computer-assisted argumentation have drawn on dialectical models of argumentation. When used to assist public policy planning, such systems also raise questions of political legitimacy. Drawing on deliberative democratic theory, we elaborate normative criteria for deliberative legitimacy and illustrate their use for assessing two argumentation systems. Full assessment of such systems requires experiments in which system designers draw on expertise from the social sciences and enter into the policy deliberation itself at the level of participants.
Similar content being viewed by others
Notes
For an introduction, see Benfer et al. 1990.
One can discern a natural evolution from knowledge systems to argumentation systems in the increasing concern with providing users with the underlying explanation for the system’s conclusion (or advice). Although developers of knowledge systems sought from the start to have their systems explain or justify their conclusions, early expert systems offered little in the way of explanation beyond high-level traces of the inference rules invoked in the chain of reasoning (Jackson 1986). It should be noted, however, that argumentation systems do more than provide detailed explanations of their reasoning. Indeed, in many ways the hallmark of an argumentation system is that it makes explicit use of the structure of the explanation, the interlocking reasons for and against a proposition, in order to determine its conclusions. Applications using some model of argumentation have included systems for: medical domains (Krause et al. 1995; Fox and Das 2000); legal domains (Gordon 1994; Verheij 1998; Bench-Capon et al. 2003); public policy decision support (Gordon and Karacapilidis 1997; Gordon et al. 1997; Karacapilidis et al. 1997); geopolitical risk prediction (Seffers 1998); scientific discourse (McBurney and Parsons 2000, 2001b); software design (Stathis 2000); and autonomous agent dialogues (Parsons et al. 1998; Sierra et al. 1998; Dignum et al. 2000). Carbogim et al. (2000) present a review of such applications.
As Haklay notes in a review of information technology for environmental decision-making, the philosophical and ethical aspects of information systems design are rarely made explicit or even explored (Haklay 2001).
The GMD National Research Center for Information Technology became part of the Fraunhofer Gesellschaft in 2001.
Much of the research in the field of AI and law appears devoted to developing systems which take an orrery role, formalizing the reasoning processes used by decision-makers so as to better understand them (Bench-Capon et al. 2003).
Likewise, systems of autonomous software agents assume decision-making is being undertaken by computational entities, and much of the research effort of second-generation electronic commerce, for instance, is directed at such automated decision-making (Jennings et al. 2001).
E.g., Buchanan and Shortliffe (1984); in Chap. 30 of this work, the authors consider quality evaluation methods for decision support systems. Greenberg (1987) also considers evaluation issues for such systems, focusing his discussion on the validation of the inference rules used by the system. Taylor (1991) briefly discusses evaluation questions as part of an exploration of the wider organizational issues associated with deployment of these systems. Parker (2000) proposes a design methodology based on the types of questions likely to be asked by a user of the system. While promising, this approach seems more appropriate for what we have termed knowledge systems (those encoding expert knowledge) than for argumentation systems.
For example, the SimCoast expert system of the UK’s Centre for Coastal and Marine Sciences was developed to provide assistance to marine coastal environment decision-makers in developing nations (McGlade 1999). However, the expertise encoded in the system embodies a specific Weltanschauung, that of a standardized western scientific ontology, which may not accord with the world views or ontologies of non-scientist users in the developing world. Moreover, Western expertise may actually distort the perception of the local reality, as shown by the example of deforestation in West Africa (Fairhead and Leach 1998). Using developing-country residents as the “experts” for the design phase may well have led to a different system.
There has been considerable research on this variance (see, e.g., Nisbett and Ross 1980; Kahneman et al. 1982). In a recent review of the limited research into how people make important medical decisions, Schneider concluded that patients make decisions quite differently from the ways proposed by normative decision theory or used by experts; however, we have few means to measure the quality of medical decisions. Selecting one procedure or course of treatment usually precludes the selection of alternatives, and so strict comparison of results of alternative decision options at an individual level is impossible. The diversity and complexity of individual circumstances and medical aetiologies make comparisons at an aggregated level also problematic (Schneider 1998).
Developers of public mobile satellite communications networks such as Iridium and ICO, for example, had lead times of a decade for designing, manufacturing and deploying the innovative satellite technology they required (McBurney and Parsons 2002a). To guide this work, the intending investors sought the advice of market researchers on the size of the potential market for mobile satellite services. In the particular decade concerned (1989–1999) demand for terrestrial cellular services grew much faster than anyone had forecast at the outset of the period, to the detriment of demand for mobile satellite services at the end of the decade. In major part this growth in terrestrial cellular demand was spurred by technological changes and the spread of cellular network coverage unanticipated in 1989. Was the advice given by the market researchers wrong because it did not predict unanticipated events, or, if anticipated, did not sufficiently emphasize unlikely events? The advice may not have been wrong if the world had been otherwise in the subsequent decade. Most management consultancy is not assessable or assessed for these two reasons (an observation based on the second author’s decade of experience as a management consultant).
In the one quality assessment of decision support systems known to us, Groothuis and Svensson (2000) assessed the quality of decisions made with the help of computer systems in the provision of welfare assistance in The Netherlands, comparing the actual determination reached in a sample of welfare assistance cases with the decision which should have been made under the relevant laws. The results of this assessment showed that decision quality varied according to the extent to which the system provided support for the complex administrative tasks involved. For those cases where the system provided full support, few human errors were made; in other cases, where only limited support was provided, decision errors were more frequent. The authors concluded that this was due to the human decision-makers trusting the advice of the system even when such trust was not warranted, thus revealing weaknesses in the human decision-makers rather than in the decision support systems.
For example, a system designed to support water-flow management through a dam will only be required to recommend responsive actions for 200-year floods on average once every 200 years. There may be insufficient data to design the system or to predict its performance in these circumstances, and possibly only one case every 200 years on which to base a live assessment of that performance. Moreover, if a system is designed for an entirely new activity how does one assess the adequacy of its advice? The various intelligent agent systems currently being deployed by NASA for control of autonomous spacecraft are examples of systems which undertake completely new activities. How is it possible to rate their performance in any other but crude terms, such as overall mission success versus non-success? (NASA 1999).
For a well-known statement of the pluralist model, which draws on James Madison’s Federalist Paper no. 10, see Dahl (1956).
In Hitchcock et al. (2001), the characteristic of sharing information is taken to be one that distinguishes deliberation from negotiation dialogues (in contrast to the definition in Walton and Krabbe 1995). In contrast, because much of the research focus in the area of intelligent multi-agent software systems has been on automated negotiation (Jennings et al. 2001), this self-transformative condition is not satisfied by all agent systems.
For a review of automated negotiation systems, see Jennings et al. (2001).
By contrast, in systems of autonomous software agents using argumentation, such as the team-formation systems of Dignum et al. (2000), the entirety of the dialogue occurs inside the system.
Such questions arise, for example, in the use of intelligent systems in medical domains. See, for example, Emery et al. (1999).
We focus on the Risk Agora because the dialogue rules are explicit in the system formalism. This is not to deny that certain features of the Zeno argumentation framework could be translated into such rules.
Although similar procedural criteria have been proposed for assessment of automatic electronic auction systems (Sandholm 1999), to our knowledge this is the first time such proposals have been made for argumentation-based computer systems.
Cf. Hitchcock’s “externalization” property, which requires that rules in the system “be formulated in terms of verifiable linguistic behavior” (Hitchcock 1991).
For example, Gardenfors (1994) discusses the reasoning processes used by illiterate Uzbeki peasants, and argues that apparent violations of deductive inference rules are, in fact, differential assessments of argument premises according to the perceived experience of the proponent of the premise. A formalism which did not represent this aspect of argument premises would not be able to represent the styles of arguments used by the Uzbekis.
References
Alexy R (1990) A theory of practical discourse. In: Benhabib S, Dallmayr F (eds) The communicative ethics controversy. MIT Press, Cambridge pp 151–190. Translation by D. Frisby of: “Eine theorie des praktischen Diskurses”. In: Oelmuller W (ed) Normenbegrundung-Normendurchsetzung. Schoningh, Paderborn, Germany, 1978
Alty JL, Coombs MJ (1984) Expert systems: concepts and examples. National Computer Centre Publications, Manchester
Beetham D (1998) Legitimacy. In: Craig E (ed) Routledge encyclopedia of philosophy. Routledge, London. Retrieved 21 July 2004, from <http://www.rep.routledge.com/article/S034SECT5 >
Bell C (1978) Studying the locally powerful: personal reflections on a research career. In: Bell C, Encel S (eds) Inside the whale: ten personal accounts of social research. Pergamon Press, Sydney
Bench-Capon TJM, Freeman J, Hohmann H, Prakken H (2003) Computational models, argumentation theories and legal practice. In: Reed C, Norman T (eds) Argumentation machines: new frontiers in argument and computation. Kluwer, Dordrecht, pp 85–120
Benfer RA, Brent EE, Furbee L (1990) Expert systems. Sage, Newbury Park
Bledsoe CH, Robey KM (1986) Arabic literacy and secrecy among the Mende of Sierra Leone. Man 21(2):202–226
Bohman J (1996) Public deliberation: pluralism, complexity and democracy. MIT Press, Cambridge
Bohman J, Rehg W (eds) (1997) Deliberative democracy: essays on reason and politics. MIT Press, Cambridge
Buchanan BG, Shortliffe EH (1984) Rule-based expert systems: The MYCIN experiments of the stanford heuristic programming project. Addison-Wesley, Reading
Carbogim DV, Robertson DS, Lee JR (2000) Argument-based applications to knowledge engineering. Knowl Eng Rev 15(2):119–149
Cohen J (1989) Deliberation and democratic legitimacy. In: Hamlin A, Pettit P (eds) The good polity. Blackwell, Oxford, pp 17–34
Collins HM, Evans R (2002) The third wave of science studies: studies of expertise and experience. Soc Stud Sci 32:235–296
Dahl RA (1956) A preface to democratic theory. University of Chicago Press, Chicago
Dignum F, Dunin-Kceplicz B, Verbrugge R (2000) Agent theory for team formation by dialogue. In: Castelfranchi C, Lesperance Y (eds) Pre-proceedings of the seventh international workshop on agent theories, architectures, and languages (ATAL-2000), Boston, MA, pp 141–156
Dung PM (1995) On the acceptability of arguments and its fundamental role in nonmonotonic reasoning, logic programming and n-persons games. Artif Intell 77:321–357
Elster J (1986) The market and the forum. In: Elster J, Aanund A (eds) The foundations of social choice theory. Cambridge University Press, Cambridge, pp 103–132
Emery J, Walton R, Coulson A, Glasspool DW, Ziebland S, Fox J (1999) Computer support for recording and interpreting family histories of breast and ovarian cancer in primary care (RAGs): qualitative evaluation with simulated patients. Br Med J 319:32–36
Ess C (1996) The political computer: democracy, CMC, and Habermas. In: Ess C (ed) Philosophical perspectives on computer-mediated communication. SUNY Press, Albany, NY, pp 197–230
Fairhead J, Leach M (1998) Reframing deforestation: global analysis and local realities: studies in West Africa. Routledge, London
Feenberg A (1999) Questioning technology. Routledge, New York
Forester J (1999) The deliberative practitioner: encouraging participatory planning processes. MIT Press, Cambridge, MA
Fox J, Das S (2000) Safe and sound: artificial intelligence in hazardous applications. MIT Press, Cambridge, MA
Gardenfors PG (1994) The role of expectations in reasoning. In: Masuch M, Polos L (eds) Knowledge representation and reasoning under uncertainty: logic at work. Lecture notes in artificial intelligence 808. Springer, Berlin Heidelberg New York, pp 1–16
Goldman AI (1994) Argumentation and social epistemology. J Philos 91:27–49
Goldman AI (1999) Knowledge in a social world, chap 5. Oxford University Press, Oxford, UK
Gordon TF (1994) The pleadings game: an exercise in computational dialectics. Artif Intell Law 2:239–292
Gordon TF (2003) An open, scalable and distributed platform for public discourse. Retrieved 16 July 2004 from <http://www.tfgordon.de/publications/Gordon2003a.pdf. >
Gordon TF, Karacapilidis N (1997) The Zeno argumentation framework. In: Proceedings of the 6th international conference on AI and law. ACM Press, New York, pp 10–18
Gordon TF, Karacapilidis N, Voss H, Zauke A (1997) Computer-mediated cooperative spatial planning. In: Timmermans H (ed) Decision support systems in urban planning. E & FN Spon, London, pp 299–309
Grasso F (2002) Towards a computational rhetoric. Informal Logic 22:195–229
Greenberg HJ (1987) Validation of decision support systems. In: Mitra G (ed) Mathematical models for decision support. NATO ASI Series, Springer, Berlin Heidelberg New York, pp 641–657
Groothuis MM, Svensson JS (2000) Expert system support and juridical quality. In: Breuker J (ed) Proceedings of the 13th international conference on legal knowledge-based systems (JURIX-2000). Enschede, The Netherlands
Habermas J (1984) The theory of communicative action, vol. 1. Reason and the rationalization of society. Heinemann, London, UK, Translation by T. McCarthy of: Theorie des Kommunikativen Handelns, Band I, Handlungsrationalitat und gesellschaftliche Rationalisierung.Suhrkamp, Frankfurt-am-Main, 1981
Habermas J (1990) Moral consciousness and communicative action. MIT Press, Cambridge. Translation by C Lenhardt and SW-Nicholsen of: Moralbewusstsein un kommunikatives Handeln. Suhrkamp, Frankfurt-am-Main, 1983
Habermas J (1993) Justification and application: remarks on discourse ethics. MIT Press, Cambridge, MA. Translation by CP Cronin of: Erläuterung zur Diskursethik. Suhrkamp, Frankfurt-am-Main, 1991
Habermas J (1996) Between facts and norms: contributions to a discourse theory of law and democracy. MIT Press, Cambridge, MA. Translation by W. Rehg of Faktizität und Geltung, Suhrkamp, Frankfurt-am-Main, 1992
Haklay M (2001) Public environmental information systems: challenges and perspectives. PhD Thesis. Department of Geography, University College, London, UK
Hamblin CL (1971) Mathematical models of dialogue. Theoria 37:130–155
Hintikka KJJ (1968) Language-games for quantifiers. Americal philosophical quarterly monograph series 2: studies in logical theory. Blackwell, Oxford, pp 46–72
Hitchcock D (1991) Some principles of rational mutual inquiry. In: van Eemeren F et al. (eds) Proceedings of the 2nd international conference on argumentation. SICSAT, Amsterdam, pp 236–243
Hitchcock D (1992) Relevance. Argumentation 6:251–270
Hitchcock D, McBurney P, Parsons S (2001) A framework for deliberation dialogues. In: Hansen HV, Tindale CW, Blair JA, Johnson RH (eds) Proceedings of the 4th biennial conference of the Ontario society for the study of argumentation (OSSA 2001), Ontario, Windsor
Jackson P (1986) Introduction to expert systems. Addison-Wesley, Wokingham
Jennings NR, Faratin P, Lomuscio AR, Parsons S, Sierra C, Wooldridge M (2001) Automated negotiation: prospects, methods and challenges. Group Decis Negot 10(2):199–215
Johnson R (2000) Manifest rationality: a pragmatic theory of argument. Lawrence Erlbaum Associates, Mahwah, NJ, USA
Kahneman D, Slovic P, Tversky A (eds) (1982) Judgment under uncertainty: heuristics and biases. Cambridge University Press, Cambridge
Karacapilidis N, Papadias D, Gordon T, Voss H (1997) Collaborative environmental planning with GeoMed. Eur J Oper Res 102(2):335–346
Kirwan B, Ainsworth LK (1993) A guide to task analysis. Taylor and Francis, London
Krause P, Ambler S, Elvang-Gorannson M, Fox J (1995) A logic of argumentation for reasoning under uncertainty. Comput Intell 11(1):113–131
Kriesberg L, Northrup TA, Thorson SJ (eds) (1989) Intractable conflicts and their transformation. Syracuse University Press, Syracuse
Kuflik A (1999) Computers in control: rational transfer of authority or irresponsible abdication of autonomy. Ethics Inform Technol 1(3):173–184
Lind EA, Tyler TR (1988) The social psychology of procedural justice. Plenum, New York
Lindley DV (1985) Making decisions, 2nd edn. Prentice-Hall, London
Mackenzie JD (1979) Question-begging in non-cumulative systems. J Philos Log 8:117–133
Märker O, Hagedorn H, Trénel M, Gordon TF (2002) Internet-based citizen participation in the city of Esslingen: relevance – moderation – software. In: Schrenk M (ed) CORP 2000 – who plans Europe’s future? Institute für EDV-gestützte Metbhoden in Architektur und Raumplanung der Technischen Universität Wien, Vienna, Austria
Mayo DG, Hollander RD (eds) (1991) Acceptable evidence: science and values in risk management. Oxford University Press, Oxford
McBurney P, Parsons S (2000) Risk Agoras: dialectical argumentation for scientific reasoning. In: Boutilier C, Goldszmidt M (eds) Proceedings of the 16th conference on uncertainty in artificial intelligence (UAI-2000). Morgan Kaufmann, Stanford, CA, USA, pp 371–379
McBurney P, Parsons S (2001a) Intelligent systems to support deliberative democracy in environmental regulation. Inf Commun Technol Law 10(1):33–43
McBurney P, Parsons S (2001b) Representing epistemic uncertainty by means of dialectical argumentation. Ann Math Artif Intell 32 (1–4):125–169
McBurney P, Parsons S (2002a) Using belief functions to forecast demand for mobile satellite services. In: Srivastava RP, Mock T (eds) Belief functions for business decisions. Physica, New York, pp 281–315
McBurney P, Parsons S (2002b) Games that agents play: a formal framework for dialogues between autonomous agents. J Log Lang Inform 11(3):315–334
McCarthy T (1999) Legitimacy and diversity: dialectical reflections on analytic distinctions. In: Rosenfeld M, Arato A (eds) Habermas on law and democracy. University of California Press, Berkeley, USA, pp 115–153
McGlade J (1999) Indigenous knowledge and the coastal environment: the SimCoast system. Presentation to ESRC/GEC seminar on environmental knowledge: uncertainty, authority and responsibility, Centre for the Study of Environmental Change, University of Lancaster, Lancaster, UK, 22 November 1999
Michelman FI (1988) Law’s republic. Yale Law Rev 97(8):1493–1537
Michelman FI (1989) Conceptions of democracy in American constitutional argument: the case of pornography regulation. Tennessee Law Rev 56:291–319
Moor J (1979) Are there decisions computers should never make? Nat Sys 1:217–229
Morgan MG (1993) Risk analysis and risk management. Sci Am July:32–41
NASA (1999) Computer program assumes spacecraft command. Press release, National Aeronautics and Space Administration, Pasadena, CA, USA. Available from: http://www.jpl.nasa.gov/releases/99/remote.html. Cited 17 May 1999
Nisbett R, Ross L (1980) Human inference: strategies and shortcomings of social judgment. Prentice-Hall, Englewood Cliffs
Parker C (2000) Requirements analysis and evaluation of decision support systems: the question approach. In: Reid J, Lalmas M (eds) Proceedings of the British computer society/institution of electrical engineering workshop on the evaluation of information management systems. Department of Computer Science, Queen Mary College, University of London, London, September 2000
Parsons S, Sierra C, Jennings NR (1998) Agents that reason and negotiate by arguing. J Log Comput 8(3):261–292
Pera M (1994) The discourses of science. University of Chicago Press, Chicago
Prakken H, Vreeswijk G (2001) Logics for defeasible argumentation. In: Gabbay D (ed) Handbook of philosophical logic, 2nd edn, vol 4. Kluwer, Dordrecht, The Netherlands, pp 218–319
Rawls J (1996) Political liberalism. Columbia University Press, New York
Reed C (1998) Generating arguments in natural language. PhD Thesis, University College, University of London
Reed C, Norman T (eds) (2003) Argumentation machines: new frontiers in argument and computation. Kluwer, Dordrecht
Rehg W (1997a) Reason and rhetoric in Habermas’s theory of argumentation. In: Jost W, Hyde MJ (eds) Rhetoric and hermeneutics in our time: a reader. Yale University Press, New Haven, pp 358–377
Rehg W (1997b) Legitimacy and deliberation in epistemic conceptions of democracy: between Habermas and Estlund. Mod Schoolman 74:355–374
Rehg W (1999) Intractable conflicts and moral objectivity: a dialogical, problem-based approach. Inquiry 42:229–258
Rescher N (1977) Dialectics: a controversy-oriented approach to the theory of knowledge. State University of New York Press, Albany
Rittel HWJ, Webber MM (1973) Dilemmas in a general theory of planning. Policy Sci 4:155–169
Sandholm TW (1999) Distributed rational decision making. In: Weiss G (ed) Multiagent systems: a modern introduction to distributed artificial intelligence. MIT Press Cambridge, pp 201–258
Schmidt-Belz B, Rinner C, Gordon TF (1998) GeoMed for urban planning—first user experiences. In: Proceedings of the 6th ACM international symposium on advances in geographic information systems. Washington, DC, USA
Schneider F (undated) Democracy goes on-line: Inernet-based citizen participation in the zoning plan. from <http://www.mediakomm.net/documents/kongress/esslingen/schneider_en.pdf. >. Cited 16 July 2004
Schneider CE (1998) The practice of autonomy: patients, doctors and medical decisions. Oxford University Press, Oxford
Schumpeter JA (1976) Capitalism, socialism and democracy. Harper, New York
Seffers GI (1998) Crisis system for president: DARPA’s project Genoa would speed US decision-making. Defense News 13(13):1
Sierra C, Jennings NR, Noriega P, Parsons S (1998) A framework for argumentation-based negotiation. In: Singh MP, Rao A, Wooldridge MJ (eds) Intelligent agents IV: agent theories, architectures, and languages. Proceedings of the 4th international ATAL workshop, lecture notes in artificial intelligence no. 1365, Springer, Berlin Heidelberg New York, pp 177–192
Stathis K (2000) A game-based architecture for developing interactive components in computational logic. Electron J Funct Log Program 2000(5)
Taylor A (1991) Organizational and social implications. In: Bench-Capon T (ed) Knowledge-based systems and legal applications. Academic, London, pp 309–327
Tindale CW (1999) Acts of arguing. State University of New York Press, Albany
Tonnelier CAG, Fox J, Judson PN, Krause PJ, Pappas N, Patel M (1997) Representation of chemical structures in knowledge-based systems: the StAR system. J Chem Inf Comput Sci 37:117–123
Toulmin SE (1958) The uses of argument. Cambridge University Press, Cambridge
Tyler TR (1990) Why people obey the law. Yale University Press, New Haven
Vaughan D (1996) The challenger launch decision: risky technology, culture, and deviance at NASA. University of Chicago Press, Chicago, IL, USA
Verheij B (1998) ArguMed: a template-based argument mediation system for lawyers. In: Hage JC, Bench-Capon TJM, Koers AW, de Vey Mestdagh CNJ, Grutters CAFM (eds) Proceedings of the 11th conference of legal knowledge-based systems (JURIX-98). Gerard Noodt Instituut, Nijmegen, The Netherlands, pp 113–130
Verheij B (1999) Automated argument assistance for lawyers. In: Proceedings of the 7th international conference on artificial intelligence and law. ACM Press, New York City, pp 43–52
Walton DN (1995) A pragmatic theory of fallacy. University of Alabama Press, Tuscaloosa
Walton DN (2000) The place of dialogue theory in logic, computer science and communication studies. Synthese 123:327–346
Walton DN, Krabbe ECW (1995) Commitment in dialogue: basic concepts of interpersonal reasoning. SUNY Series in Logic and Language. State University of New York Press, Albany
Warnke G (1999) Legitimate differences. University of California Press, Berkeley
Weber M (1978) Economy and society, 2 vols. Translated by Roth G, Wittich C (eds), University of California Press, Berkeley, CA, USA
Webler T, Tuler S, Krueger R (2001) What is a good public particpation process? Five perspectives from the public. Environ Manage 27:435–450
Weizenbaum J (1976) Computer power and human reason: from judgment to calculation. Freeman, San Francisco
Wynne B (1989) Sheepfarming after Chernobyl: a case study in communicating scientific information. Environment 31(2):10–39
Acknowledgements
This work was partly funded by the British Engineering and Physical Sciences Research Council (EPSRC) through a PhD studentship. We gratefully acknowledge this support. We are also grateful for discussions on these topics with Trevor Bench-Capon, Rod Girle, Muki Haklay, David Hitchcock and Bart Verheij. We also thank Thomas Gordon and R. Prescott Loui for their feedback on an earlier draft of this paper.
Author information
Authors and Affiliations
Corresponding author
Rights and permissions
About this article
Cite this article
Rehg, W., McBurney, P. & Parsons, S. Computer decision-support systems for public argumentation: assessing deliberative legitimacy. AI & Soc 19, 203–228 (2005). https://doi.org/10.1007/s00146-004-0313-2
Received:
Accepted:
Published:
Issue Date:
DOI: https://doi.org/10.1007/s00146-004-0313-2