Argumentation Graphs with Constraint-Based Reasoning for Collaborative Expertise
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Open Archive Toulouse Archive Ouverte OATAO is an open access repository that collects the work of Toulouse researchers and makes it freely available over the web where possible This is an author’s version published in: http://oatao.univ-toulouse.fr/21334 To cite this version: Doumbouya, Mamadou Bilo and Kamsu-Foguem, Bernard and Kenfack, Hugues and Foguem, Clovis Argumentation graphs with constraint-based reasoning for collaborative expertise. (2018) Future Generation Computer Systems, 81. 16-29. ISSN 0167-739X Any correspondence concerning this service should be sent to the repository administrator: [email protected] Argumentation graphs with constraint-based reasoning for collaborative expertise Mamadou Bilo Doumbouya a,b , Bernard Kamsu-Foguem a,*, Hugues Kenfack b, Clovis Foguem c,d a Université de Toulouse, Laboratoire de Génie de Production (LGP), EA 1905, ENIT-INPT, 47 Avenue d'Azereix, BP 1629, 65016, Tarbes Cedex, France b Université de Toulouse, Faculté de droit, 2 rue du Doyen Gabriel Marty, 31042 Toulouse cedex 9, France c Université de Bourgogne, Centre des Sciences du Goût et de l'Alimentation (CSGA), UMR 6265 CNRS, UMR 1324 INRA, 9 E Boulevard Jeanne d'Arc, 21000 Dijon, France d Auban Moët Hospital, 137 rue de l’hôpital, 51200 Epernay, France h i g h l i g h t s • Reasoning underlying the remote collaborative processes in complex decision making. • Abstract argumentation framework with the directed graphs to represent propositions • Conceptual graphs for ontological knowledge modelling and formal visual reasoning. • Competencies and information sources for the weighting of shared advices/opinions. • Constraints checking for conflicts detection according to medical–legal obligations. a b s t r a c t Collaborative processes are very important in telemedicine domain since they allow for making right de- cisions in complex situations with multidisciplinary staff. When modelling these collaborative processes, some inconsistencies can appear. In semantic modelling (conceptual graphs), these inconsistencies are verified using constraints. In this work, collaborative processes are represented using an argumentation Keywords: system modelled in a conceptual graph formalism where inconsistencies could be particular bad attack Argumentation theory relation between arguments. To overcome these inconsistencies, two solutions are proposed. The first one Decision making is to weight the arguments evolving in the argumentation system on the basis of the competencies of the Conceptual graphs health professionals and the credibility of the sources justifying their advice (arguments), and the second Inconsistencies one is to model some law concepts as constraints in order to check their compliance of the collaborative Weighting process. Medical deontology 1. Introduction medical professionals by using argumentation [5] and conceptual graphs. In these previous works, we did not take into consideration Conceptual graphs introduced by [1] have been used in several the notion of constraints which is essential in medicine. Indeed, in works for knowledge representation, modelling and visualisation. situations where consents must be given such as medical proce- Very often, the knowledge base building process can lead to incon- dures, patients and other subjects have to deal with constraints [6]. sistencies. To overcome these issues, constraints can be used and These constraints defined in [6] are categorised as information applied to the concerning knowledge base. constraints and they are in number of three [6]: (i) constraints An effective integration of constraints in collaborative processes from the concept of a disease, (ii) constraints from the diffusion of must therefore become a central feature of consistent develop- medical innovation, (iii) constraints from withholding information. ment efforts in argumentative reasoning. In fact, in our previous These are few examples of constraints in the medical domain. works [2–4], we have modelled collaborative processes between We have noticed that during collaborative medical processes modelled with the Dung argumentation system [2,4] inconsis- tencies can appear (for example bad attack relation due to the * Corresponding author. E-mail addresses: [email protected] (M.B. Doumbouya), [email protected] non-compliance with medical deontology concepts or arguments (B. Kamsu-Foguem), [email protected] (H. Kenfack), given by a medical professional that should not attack another [email protected] (C. Foguem). argument). Given that the collaborative processes are modelled using the Dung argumentation framework, itself represented in conceptual graph formalism which can support the expression of semantic constraints in order to check if there are inconsistencies or not. The solution proposed in this work is to use some laws gov- erning remote medical collaboration that will be modelled as con- straints because the laws are obligations and must be respected. Moreover, given that in collaborative medical processes the stake- holders give some advice, the line of reasoning is to weight pieces of advice and then use these weighted pieces of advice as con- straints. In our work, the bad attacks represent the attack that starts from one argument to another with greater weight or attacks that do not comply with the guidelines of medical deontology. The detected bad attacks are ignored or removed from the graph of attacks [7,8], then the acceptability semantics are computed on the remaining attacks by using the algorithms proposed in [3]. The challenge in this paper is to model these constraints in conceptual graphs formalism in a real case study of remote collab- oration between medical professionals. The novelty in this work is the fact of combining argumentation and conceptual graphs while Fig. 1. Graph of attacks. taking in consideration constraints; the whole applied to remote medical practice such as teleexpertise which is a medical practice that involves at least two medical professionals who collaborate by Definition 3. Acceptability semantics. sharing patients' information and experiences aimed at managing Let AF D (A; R) be an argumentation framework and B ⊆ A a (diagnosis and treatments) a patient. The advantage of our solution conflict-free set. is to bring assistive tools to judicial experts in case of litigation after an act of teleexpertise while providing consistent collaborations • B is an admissible extension iff it defends any element in B. between remote medical professionals. • B is a preferred extension iff B is a maximal (w.r.t. set ⊆) In the coming sections, we will recall some basic notions of con- admissible set. ceptual graphs and constraints, talk about some related works and • B is a stable extension iff 8 a 2 A n B; 9 b 2 by a case study we will propose a modelling of some constraints B such that (a; b) 2 R. directly in CoGui software1 [9]. We end this paper by a results and • B is a complete extension iff B is admissible and 8 a 2 A, if a discussions section and a conclusion section. is acceptable compared to B, then a 2 B. • B is a grounded extension iff B is complete and @ C such that 2. Background C ⊂ B. 2.1. Argumentation framework Example 3. Referring to Fig. 1: • Admissible extensions: f;g, feg, fd; eg, fbg, fb; dg, fb; eg, Given that we are dealing with Dung argumentation frame- fb; d; eg, fcg, fb; cg, fc; dg, fb; c; dg, fc; eg, fb; c; eg, fc; d; eg, work [5], a brief explanation of the generalities of the concepts fb; c; d; eg. that we are going to refer to in this paper will permit better • Preferred extension: fb; c; d; eg. understanding of our proposal. Property 1. Arguments status D Definition 1. An argumentation framework is a couple F (A; R), Let AF D (A; R) be an argumentation framework and "1;:::;"n where A is a set of arguments and R ⊆ A×A is the attack relation. its extensions under a given semantics. Let a 2 A. The couple (a; b) 2 R means that a attacks b. It is said that an • 2 Tn argument a 2 A is defended (in F) by a set S ⊆ A if, 8 b 2 A a is skeptically accepted iff a 1"i. • 9 2 such that (b; a) 2 R, 9 c 2 S such that (c; b) 2 R. a is credulously accepted iff "i, such that a "i. • 62 Sn a is rejected iff a 1"i. Example 1. Let AF D (A; R) be an argumentation framework with A D fa; b; c; d; eg and R D f(a; b); (a; c); (a; d); (b; a); (c; a); (e; a)g. 2.2. Conceptual graphs, projection operation and constraints Graphically AF is represented by Fig. 1 depicting a graph of attacks. In argumentation framework, it is important to remember that In this section, we will recall the background of conceptual there exist some key concepts helping in the decision-making graphs and constraints drawn from [10]. The argumentation sys- process. These concepts are: conflict-free sets, acceptability se- tem [5] used in this work is well explained in our previous mantics and arguments status [5]. works [2–4,11]. Definition 2. Conflict-free set. 2.2.1. Conceptual graphs Let AF D (A; R) be an argumentation framework and B ⊆ A. B Conceptual graphs have been introduced by [1] in 1984. It is a is conflict-free if there are no α; β 2 B such that (α; β) 2 R. formalism for knowledge representation and reasoning. A concep- tual graph is a bipartite oriented graph: Example 2. Referring to Fig. 1, {d,e} is conflict-free while {a,b,c} is • Bipartite: two kinds of nodes: concepts and relations; not. • Nodes are linked by oriented arcs or numbered arcs; • An arc always links a concept to a relation; 1 Conceptual Graphs Graphical User Interface. • A concept node can be isolated (not linked). Fig. 2. Two possible representations of conceptual graph.