Gerhard Lakemeyer

Continuous requirements management for organisation networks: a (dis)trust-based approach

Recently, viewpoint resolution methods which make conflicts productive for requirements engineering have gained popularity in organisational information systems. However, when extending such methods beyond organisational boundaries to inter-organisational social networks, sociological research indicates that a delicate balance of trust in individuals, confidence in the network as a whole, and watchful distrust becomes a key success factor. We capture these relationships in the so-called TCD (Trust–Confidence–Distrust) approach and demonstrate how this approach can be supported by a dynamic requirements engineering environment that combines the structural analysis of strategic dependencies and rationales, with the interaction between planning, tracing, and communicative action. An example drawn from an ongoing case study in entrepreneurship networks illustrates our approach, complemented by a brief sketch of a prototypical implementation of a simulation environment based on our methodology.

Requirements modeling for organization networks: a (dis)trust-based approach

Recently, viewpoint resolution methods which make conflicts productive have gained popularity in requirements engineering for organizational information systems. However, when extending such methods beyond organizational boundaries to social networks, sociological research indicates that a delicate balance of trust in individuals, confidence in the network as a whole, and watchful distrust becomes a key success factor. We capture these relationships in the so-called TCD (Trust-Confidence-Distrust) approach and demonstrate how this approach can be supported by a dynamic requirements engineering environment that combines the structural analysis of strategic dependencies and rationales, with the interaction between planning, tracing, and communicative action. An example drawn from an ongoing case study in entrepreneurship networks illustrates our approach.

Deliberation in a metadata-based modeling and simulation environment for inter-organizational networks

In the emerging field of database centric business process management, inter-organizational networks of people, information and communication systems are often described by the interplay between individual goals and actions and the strategic dependencies among individuals and subgroups. Our research aims at improving requirements engineering for such networks by not just representing these goals and dependencies statically, but also by studying the dynamic interactions between both. In previous work, we proposed the prototype environment SNet for the representation and dynamic simulation of agent-based designs for inter-organizational networks. A key feature of SNet was the automatic translation of extended i* models into the action language ConGolog. While this allowed the simulation of agent networks specified in i*, the resulting agents were purely reactive. In this paper, we explicitly incorporate deliberation into the agent design of SNet. At the level of i* deliberation is represented in terms of goals which are satisfiable by different tasks or agents. Utilities are modeled, in part, using the existing concept of softgoals, which are given a quantitative interpretation. At the level of ConGolog, decision-theoretic features are built into the interpreter, which drives the simulations, and the process of delegating tasks to other agents is explicitly represented.

Deliberation in a modeling and simulation environment for inter-organizational networks

Inter-organizational networks of people, information and communication systems are often described by the interplay between individual goals and actions and the strategic dependencies among individuals and subgroups. Our research aims at improving requirements engineering for such networks by not just representing these goals and dependencies statically, but also by studying the dynamic interactions between both. In previous work, we proposed the prototype environment SNet for the representation and dynamic evaluation of agent-based designs for inter-organizational networks. A key feature of SNet was the automatic translation of extended i* models into the action language ConGolog. While this allowed the simulation of agent networks specified in i*, the resulting agents were purely reactive, which limits the usefulness of the system, in particular as a decision-support tool for network members, who need to evaluate the utility of different courses of action. In this paper we propose to remedy the situation by explicitly incorporating deliberation into the agent design of SNet. At the level of i*, deliberation is represented in terms of goals which are satisfiable by different tasks or agents. Utilities are modeled, in part, using the existing concept of softgoals, which are given a quantitative interpretation. At the level of ConGolog, decision-theoretic features are built into the interpreter, which drives the simulations, and the process of delegating tasks to other agents is explicitly represented.

SNet reloaded: roles, monitoring and agent evolution

In previous work, we proposed the prototype environment SNet for the representation and dynamic evaluation of agent-based designs for inter-organizational networks. A key feature of SNet is the automatic translation of extended i* models into the action language ConGolog. In order to run realistic simulations, the resulting agents are deliberative in that they can choose between different courses of action according to some utility measure. When applying SNet to modelling an existing entrepreneurship network, we discovered a number of deficiencies of our current proposal, in particular, the lack of a role concept, the ability to monitor the execution of plans that depend on other agents contributions and the ability to model agents that evolve over time. In this paper we will sketch the example domain and discuss how these new features can be incorporated in the SNet framework.

Comparing three formal analysis approaches of the tropos family

Tropos is a software development methodology founded on concepts used to model early requirements, the i* framework. In addition to a methodological framework, research addresses also formal analysis support. In previous work, we proposed the prototype environment SNet based on the Trust-Confidence-Distrust (TCD) approach for the representation and dynamic evaluation of agent-based designs for inter-organizational networks. There are two major ingredients: i* for modeling the domain statically and ConGolog for analysing it dynamically via simulations. In this paper, we compare our approach with two other approaches that enrich i*/Tropos models to allow for more formal analyses, Formal Tropos and Secure Tropos. While the intended use of these is quite different from SNet, there are a number of commonalities, which will be highlighted as well as the differences that suggest a combined use, including complementary forms of analysis such as model checking versus simulation.

Modelling Actor Evolution in Agent-Based Simulations

Agent-based simulations have proven to be suitable to investigate many kinds of problems, especially in the field of social science. But to provide useful insights, the behaviour of the involved, simulated actors needs to reflect relevant features of the real world. In this paper, we address one particular aspect in this regard, namely the correct reflection of an actors evolution during a simulation. Very often some knowledge exists about how an actor can evolve, for example, the typical development stages of entrepreneurs when investigating entrepreneurship networks. We propose to model this knowledge explicitly using evolution links between roles enriched with suitable conditions and extend i* , an agent- and goal-oriented modelling framework, thereby. We provide a mapping to the simulation environment ConGolog that serves as an intermediary approach between not providing change of behaviour at all and very open approaches to behaviour adaptation such as learning.

Using BPEL Process Descriptions for Building Up Strategic Models of Inter-organizational Networks

abstract In previous work, we proposed the prototype environment SNet for the representation and dynamic evaluation of agent-based designs for inter-organizational networks. A key feature of SNet is the automatic translation of extended i* models into the action language ConGolog. An issue we have not yet considered is how to arrive at the foundational and hopefully realistic i* model. Currently there is no support to incorporate information from already existing descriptions of business processes in an enterprise. BPEL is expected to play an important role in the future by enabling interoperability of different partners’ business processes – not only in the web service domain. Once standardized a wide-spread availability of BPEL-based process descriptions can be expected. In this paper we suggest how to map BPEL descriptions into i* descriptions, thus opening the door to generating SNet simulations of business processes from BPEL descriptions.

Analyzing agent-based simulations of inter-organizational networks

Modeling and simulation is intended to support the understanding and governance of inter-organizational networks. But the analysis of the outcome of such agent-based simulations requires advanced support. Due to the complexity of emergent behavior, the modeler must firstly decide about the validity of the simulation model. Secondly, the runs must be interpreted in order to receive support on the right managerial choices. In this paper we give a list of questions addressing both issues, validation and support, for the field of inter-organizational networks and investigate four different kinds of analysis - time series analysis, association rule mining, clustering, and social network analysis - in regard to their potential for providing support.