Practical Verification of Decision-Making in Agent-Based Autonomous Systems

We present a verification methodology for analysing the decision-making component in agent-based hybrid systems. Traditionally hybrid automata have been used to both implement and verify such systems, but hybrid automata based modelling, programming and verification techniques scale poorly as the complexity of discrete decision-making increases making them unattractive in situations where complex log- ical reasoning is required. In the programming of complex systems it has, therefore, become common to separate out logical decision-making into a separate, discrete, component. However, verification techniques have failed to keep pace with this devel- opment. We are exploring agent-based logical components and have developed a model checking technique for such components which can then be composed with a sepa- rate analysis of the continuous part of the hybrid system. Among other things this allows program model checkers to be used to verify the actual implementation of the decision-making in hybrid autonomous systems

A framework for institutions governing institutions

Norms guide multi-agent systems away from being potentially anarchic towards a coordinated and collaborative society. Institutions provide an explicit, external representation of norms as well as the means to detect violations and other conditions. Each institution can be crafted individually to capture their designers’ goals, but this creates a challenge at higher levels of authority in guiding the institutional design to be coordinated with other institutions and not imposing unacceptable limits on agents’ rights. We propose to use institutions to govern and to revise institutions, following a principle widely encountered in the social world, where treaties, primary legislation, framework agreements and subsidiarity establish a regulatory space by defining norms on the form of a body of regulation. We set out a formal and computational framework, building on the InstAL model and implementation, to construct tiers of institutions, where the norms at each tier are governed by those at the tier above. Thus, agents’ behaviour is governed and monitored by a tier-1 institution, whose norms are governed and monitored by a tier-2 institution, etc.. This allows us to check the compliance of an institution with the tier above. Compliance failure generates the necessary negative examples for automatic norm-revision

Automated multi-level governance compliance checking

An institution typically comprises constitutive rules, which give shape and meaning to social interactions and regulative rules, which prescribe agent behaviour in the society. Regulative rules guide social interaction, in particular when they are coupled with reward and punishment regulations that are enforced for (non-)compliance. Institution examples include legislation and contracts. Formal institutional reasoning frameworks automate ascribing social meaning to agent interaction and determining whether those actions have social meanings that comprise (non-)compliant behaviour. Yet, institutions do not just govern societies. Rather, in what is called multi-level governance, institutional designs at lower governance levels (e.g., national legislation at the national level) are governed by higher level institutions (e.g., directives, human rights charters and supranational agreements). When an institution design is found to be non-compliant, punishments can be issued by annulling the legislation or imposing fines on the responsible designers (i.e., government). In order to enforce multi-level governance, higher governance levels (e.g., courts applying human rights) must check lower level institution designs (e.g., national legislation) for compliance; in order to avoid punishment, lower governance levels (e.g., national governments) must check their institution designs are compliant with higher-level institutions before enactment. However, checking non-compliance of institution designs in multi-level governance is non-trivial. In particular, because institutions in multi-level governance operate at different levels of abstraction. Lower level institutions govern with concrete regulations whilst higher level institutions typically comprise increasingly vague and abstract regulations. To address this issue, in this paper we propose a formal framework with a novel semantics that defines compliance between concrete lower level institutions and abstract higher level institutions. The formal framework is complemented by a sound and complete computational framework that automates compliance checking, which we apply to a real-world case study

Request driven social sensing (demonstration)

Using a scenario of collecting weather data, we present a simulation of a crowdsourcing system for social sensing using mobile sensors, driven by the requests of other users. Users control how and when their mobile sensors are used, and may exhibit cooperative and non–cooperative behaviour. To facilitate social sensing, our system includes an implementation of intelligent data aggregation. The simulator allows the analysis of user control, selfish behaviour, and data aggregation in a realistic setting

Agreeing on role adoption in open organisations

The organisational specification of a multi-agent system supports agents’ effectiveness in attaining their purpose, or prevent certain undesired behaviour from occurring. This requires that agents are able to find out about the organisational purpose and description and decide on its appropriateness for their own objectives. Organisational modeling languages are used to specify an agent system in terms of its roles, organizational structure, norms, etc. Agents take part in organisations by playing one or more of the specified roles for which they have the necessary capabilities. In this paper, we investigate the process of role adoption in the context of the well-known OperA organisational modelling language. In OperA, each organisation has a gatekeeper role responsible for admitting agents to the organisation. Agents playing the role of gatekeeper can interact with agents that want to enter the organisation in order to come to agreement on role adoption. That is, negotiate which roles they will play and under which conditions they will play them. This is possible by evaluating capability requirements for roles. We extend OperA to allow for the specification of role capabilities. This approach will be illustrated using the Blocks World for Teams (BW4T) domain.Infrastructures, Systems and ServicesTechnology, Policy and Managemen

A framework for institutions governing institutions

Norms guide multi-agent systems away from being potentially anarchic towards a coordinated and collaborative society. Institutions provide an explicit, external representation of norms as well as the means to detect violations and other conditions. Each institution can be crafted individually to capture their designers’ goals, but this creates a challenge at higher levels of authority in guiding the institutional design to be coordinated with other institutions and not imposing unacceptable limits on agents’ rights. We propose to use institutions to govern and to revise institutions, following a principle widely encountered in the social world, where treaties, primary legislation, framework agreements and subsidiarity establish a regulatory space by defining norms on the form of a body of regulation. We set out a formal and computational framework, building on the InstAL model and implementation, to construct tiers of institutions, where the norms at each tier are governed by those at the tier above. Thus, agents’ behaviour is governed and monitored by a tier-1 institution, whose norms are governed and monitored by a tier-2 institution, etc.. This allows us to check the compliance of an institution with the tier above. Compliance failure generates the necessary negative examples for automatic norm-revision

Three Categories of Context-Aware Systems

With regard to context-aware systems: some optimize system-internal processes, based on the context state at hand; others maximize the user-perceived effectiveness of delivered services, by providing different service variants depending on the situation of the user; still others are about offering value-sensitivity when the society demands so. Even though those three perspectives cover a broad range of currently relevant applications there are no widely accepted and commonly used corresponding concepts and terms. This is an obstacle to broadly understand, effectively integrate, and adequately assess such systems. We address this problem, by considering a (component-based) methodological derivation of technical (software) specifications based on underlying enterprise models. That is because context states are about the enterprise environment of a (software) system while the delivery of context-aware services is about technical (software) functionalities; hence, we need a perspective on both. We consider the SDBC (Software Derived from Business Components) approach that brings together enterprise modeling and software specification. On that basis: (a) We deliver a base context-awareness conceptualization; (b) We partially align it to agent technology because adapting behaviors to environments assumes some kind of pro-activity that is only fully covered by agent systems, in our view. We partially illustrate our proposed conceptualization and particularly - the agent technology implications, by means of a case example featuring land border security.Green Open Access added to TU Delft Institutional Repository ‘You share, we take care!’ – Taverne project https://www.openaccess.nl/en/you-share-we-take-care Otherwise as indicated in the copyright section: the publisher is the copyright holder of this work and the author uses the Dutch legislation to make this work public.Information and Communication TechnologySystem Engineerin

Shifting school populations in the Long Beach Unified School District. - Page 69

Abstract. We propose a programming framework for the implementation of norm-aware multi-agent systems. The framework integrates the N-2APL norm-aware agent programming language with the 2OPL organisation programming language. Integration of N-2APL and 2OPL is achieved using a tuple space which represents both the (brute) state of the multi-agent environment and the detached norms and sanctions comprising its normative state. To the best of our knowledge, this is the first implementation of an integrated framework for norm-aware MAS in which autonomous agents deliberate about whether to conform to the norms imposed by a normative organisation. The use of a tuple space makes it straight-forward to integrate other system components. To illustrate the flexibility of our framework, we briefly describe its application in a novel normative application, a mixed reality game called GeoSense. We show how GeoSense game rules can be expressed as conditional norms with deadlines and sanctions, and how agents can deliberate about their individual goals and the norms imposed by the game.

Mood, Personality, and Behavior Changes During Treatment with Statins: A Case Series

Psychiatric adverse drug reactions (ADRs) have been reported with statin use, but the literature regarding statin-associated mood/behavioral changes remains limited. We sought to elicit information germane to natural history and characteristics of central nervous system/behavioral changes in apparent connection with statin and/or cholesterol-lowering drug use, and delineate mechanisms that may bear on an association. Participants (and/or proxies) self-referred with behavioral and/or mood changes in apparent association with statins completed a survey eliciting cholesterol-lowering drug history, character and impact of behavioral/mood effect, time-course of onset and recovery in relation to drug use/modification, co-occurrence of recognized statin-associated ADRs, and factors relevant to ADR causality determination. Naranjo presumptive ADR causality criteria were assessed. Participants (n = 12) reported mood/behavior change that commenced following statin initiation and persisted or progressed with continued use. Reported problems included violent ideation, irritability, depression, and suicide. Problems resolved with drug discontinuation and recurred with rechallenge where attempted. Eight met presumptive criteria for “probable” or “definite” causality; others had additional factors not considered in Naranjo criteria that bear on casual likelihood. (1) Simvastatin 80 mg was followed in 5 days by irritability/depression culminating in suicide in a man in his 40s (Naranjo criteria: possible causality). (2) Simvastatin 10 mg was followed within 2 weeks by depression in a woman in her 50s (probable causality). (3) Atorvastatin 20 mg was followed in ~1 month by depression and irritability/aggression in a male in his 50s (probable causality). (4) Atorvastatin 10 mg was followed in several months by aggression/irritability and depression culminating in suicide in a man in his 40s (possible causality). (5) Fenofibrate + rosuvastatin (unknown dose), later combined with atorvastatin were followed in 1 month by aggression/irritability in a male in his 30s (probable causality). (6) Lovastatin (unknown dose and time-course to reaction) was followed by depression, dyscontrol of bipolar disorder, and suicide attempts in a male in his 40s (possible causality). (7) Atorvastatin 20 mg was followed within 2 weeks by cognitive compromise, and nightmares, depression, and anxiety culminating in suicide in a man in his teens (definite causality). (8) Simvastatin 10 mg was followed (time-course not recalled) by depression, aggression/irritability culminating in suicide in a man in his 60s (possible causality). (9) Simvastatin 20 mg then atorvastatin 10 mg were followed (time-course not provided) by irritability/aggression in a man in his 60s (definite causality). (10) Atorvastatin 10 then 20 then 40 mg were followed shortly after the dose increase by violent ideation and anxiety in a man in his 30s (probable causality). (11) Atorvastatin 20 mg and then simvastatin 20 mg were followed in 2 weeks by aggression/irritability in a man in his 50s (definite causality). (12) Lovastatin, rosuvastatin, atorvastatin, and simvastatin at varying doses were followed as quickly as 1 day by aggression, irritability, and violent ideation in a man in his 40s (definite causality). Most had risk factors for statin ADRs, and co-occurrence of other, recognized statin ADRs. ADRs had implications for marriages, careers, and safety of self and others. These observations support the potential for adverse mood and behavioral change in some individuals with statin use, extend the limited literature on such effects, and provide impetus for further investigation into these presumptive ADRs. Potential mechanisms are reviewed, including hypothesized mechanisms related to oxidative stress and bioenergetics