Graphical norms via conceptual graphs

Abstract By virtue of their nature, organisations impose rules of behaviour upon their constituent members. Such rules, which may be represented using obligations, permissions and prohibitions, form soft constraints, since actions contrary to these rules can and do occur.

2016

In this paper we will introduce a method for creating computational models of normative systems deduced from sources of norms in natural language. The authors show how to make formal interpretations of normative sources in natural language that result in a computational model, which includes explicit references to all sentences of sources of norms that are considered relevant by the interpreters to constitute a computational model. The models produced can easily be held in sync with these sources. The method presented is focused on the translation of laws in natural language into an executable computational form that can be easily validated by legal experts that have to decide on the desired interpretation of the source text. The model is tested in a prototype of a reasoner build in a newly developed domain specific language: FLINT. The model is based on Hohfeld’s fundamental legal concepts.

In this paper we introduce a new methodology to represent norms. The representation integrates heterogeneous models of norms like rules in deontic logic and nodes and external references in legal ontologies. The new methodology is inspired by Ferrara's notion of social object as "inscribed action." The representation is scalable, incremental and usable despite the vagueness and dynamics of norm change. We show how the evolution of norms is represented using incremental revisions without loosing the identity of norms over time.

2016

In this paper, the authors present their work on the development of a formal method for the interpretation of norms. This research is a continuation of the work reported in the eKNOW 2015 conference where we focused on a formal method to relate a set of norms described in natural language to the specification of a service based on these norms. In this paper, we focus on the modeling of the explicit interpretation of norms. These interpretation models are aimed to become components in our agent-role based simulations that allow to reason about the effect of norms in social reality. The method has been tested in a governmental organization for the specification of digital services. The method preserves the original concepts in sources of norms described in natural language, and delivers a translation of these norms to formal computational models. These models can be used to support institutional reasoning, i.e., reasoning about institutional facts and normative positions. Keywords-AI ...

Proceedings of the 9th international conference on Artificial intelligence and law - ICAIL '03, 2003

In this paper we discuss different types of permissions and their roles in deontic logic. We study the distinction between weak and strong permissions in the context of input/output logic, combining the logic with constraints, priorities and hierarchies of normative authorities. In this setting we observe that the notion of prohibition immunity no longer applies, and we introduce a new notion of permission as exception and a new distinction between static and dynamic norms. We show that strong permissions can dynamically change a normative system by adding exceptions to obligations, provide an explicit representation of what is permitted to the subjects of the normative system and allow higher level authorities to limit the changes that lower level authorities can do to the normative system.

The Review of Socionetwork Strategies

The paper at hand introduces and discusses a diagrammatic method to represent legal norms first developed by the second author. It is shown how this method can be used to represent not only norms and argument forms originating from classic legal methodology (legal subsumption, analogy, appeal to the contrary), but also more complex legal-theoretical phenomena, especially legal antinomies. Beyond its didactic virtues, the diagram is a useful theoretical tool for investigating how norms interact with each other and how singular actions can be considered as satisfying or violating a given norm.

FLAP, 2018

This special issue contains the journal version of four contributions to the Handbook of Normative Multi-Agent Systems (NorMAS), which will appear at College Publications. The NorMAS initiative aims at providing a comprehensive coverage of both the state of the art and future research perspectives in the interdisciplinary field of normative multi-agent systems. It is meant to be an open community effort and a service to current and future students and researchers interested in this field. We invite the readers to buy the forthcoming handbook for a full view. Please visit the website for more information and feel free to send us comments, suggestions and proposals: http://normativemas.org/ The articles in this special issue and the chapters in the handbook give a survey of the area and may also contain a more personal view. For the survey part, at least the work reported in the NorMAS conference series is discussed. Instead of just a historical overview, the authors also address new developments, open topics and emerging areas. The handbooks appeal to all disciplines, including logic, computer science, law, philosophy, and linguistics. The articles in this special issue discuss the obtained results and open challenges in modeling normative multiagent systems during the last two decades. More information can be found in the handbook on deontic logic and normative systems, or the website http://deonticlogic.org/ The first paper in this special issue formally analyses the issue of modeling norm specification and verification in multiagent systems (MAS). In particular, for Alechina et al., violation conditions of regulative norms may correspond to conditions on states, actions, or arbitrary temporal patterns. They may be specified semantically or expressed syntactically in a suitable temporal logic, or in a programming language. Verification problems for norms or rather for normative systems involve verifying consistency of norms, verifying whether violation conditions hold, and finally verifying whether a system where norms are enforced satisfies some system objective.

ArXiv, 2018

Most of the knowledge Representation formalisms developed for representing prescriptive norms can be categorized as either suitable for representing either low level or high level norms.We argue that low level norm representations do not advance the cause of autonomy in agents in the sense that it is not the agent itself that determines the normative position it should be at a particular time, on the account of a more general rule. In other words an agent on some external system for a nitty gritty prescriptions of its obligations and prohibitions. On the other hand, high level norms which have an explicit description of a norm's precondition and have some form of implication, do not as they exist in the literature do not support generalized inferences about violation like low level norm representations do. This paper presents a logical formalism for the representation of high level norms in open societies that enable violation inferences that detail the situation in which the no...

The Semantic Web–ASWC …, 2006

Defeasible reasoning is a rule-based approach for efficient reasoning with incomplete and conflicting information. Such reasoning is useful in many Semantic Web applications, like policies, business rules, brokering, bargaining and agent negotiations. Nevertheless, defeasible logic is based on solid mathematical formulations and is, thus, not fully comprehensible by end users, who often need graphical trace and explanation mechanisms for the derived conclusions. Directed graphs can assist in confronting this drawback. They are a powerful and flexible tool of information visualization, offering a convenient and comprehensible way of representing relationships between entities. Their applicability, however, is balanced by the fact that it is difficult to associate data of a variety of types with the nodes and the arcs in the graph. In this paper we try to utilize digraphs in the graphical representation of defeasible rules, by exploiting the expressiveness and comprehensibility they offer, but also trying to leverage their major disadvantage, by defining two distinct node types, for rules and atomic formulas, and four distinct connection types for each rule type in defeasible logic and for superiority relationships. The paper also briefly presents a tool that implements this representation methodology.

2005

Abstract. Defeasible reasoning is a rule-based approach for efficient reasoning with incomplete and inconsistent information. Such reasoning is useful for many applications in the Semantic Web, such as policies and business rules, agent brokering and negotiation, ontology and knowledge merging, etc. However, the syntax of defeasible logic may appear too complex for many users.