A metrics definition framework for i*

Measuring is a central task in the any engineering discipline, and modelling is not an exception. The need for measuring properties over i* models arises in different contexts. We have analysed this need over i* models of organizations, projects, systems and architectures. As a result, we have proposed a framework which includes: (a) a metamodel of i* that defines the elements that build the model; (b) a framework for the definition of metrics; (c) a collection of metrics (currently under construction) of different nature built with the framework. In this work, we present these basic concepts and discuss the applicability of the approach.Peer ReviewedPostprint (published version

Using i* to represent OSS ecosystems for risk assessment

Open Source Software (OSS) is a strategic asset for organisations thanks to its short time-to-market, the opportunity for a reduced development effort and total cost of ownership, and its customization capabilities. OSS-based solutions include projects that are developed and co-evolve within the same organisation, OSS communities, companies, and regulatory bodies, forming an articulated strategic business ecosystem. The adoption of OSS in commercial projects leads to numerous challenges in the wide spectrum of available OSS solutions and risks emerging from the intrinsic structure of an OSS project. In this position paper we devise the use of i* models for understanding the strategic perspective of OSS ecosystems, representing actors, intentional dependencies and responsibilities. We argue that these models can play a crucial role in the analysis of organisational risks inherent to OSS component adoption and in the definition of risk mitigation activities.Postprint (published version

The i* framework for goal-oriented modeling

The final publication is available at Springer via http://dx.doi.org/10.1007/978-3-319-39417-6i* is a widespread framework in the software engineering field that supports goal-oriented modeling of socio-technical systems and organizations. At its heart lies a language offering concepts such as actor, dependency, goal and decomposition. i* models resemble a network of interconnected, autonomous, collaborative and dependable strategic actors. Around this language, several analysis techniques have emerged, e.g. goal satisfaction analysis and metrics computation. In this work, we present a consolidated version of the i* language based on the most adopted versions of the language. We define the main constructs of the language and we articulate them in the form of a metamodel. Then, we implement this version and a concrete technique, goal satisfaction analys is based on goal propagation, using ADOxx. Throughout the chapter, we used an example based on open source software adoption to illustrate the concepts and test the implementation.Peer ReviewedPostprint (author's final draft

Model interchange and tool interoperability in the i* framework: a proof of concept

Peer ReviewedPostprint (published version

Using roles for OSS adoption strategy models

Increasing adoption of Open Source Software (OSS) in information system engineering has led to the emergence of different OSS adoption strategies that affect and shape organizations’ business models. OSS adoption strategies can be operationalized by i* models describing the consequences of choosing each strategy. When an organization decides to adopt an OSS component, it becomes a part of the OSS ecosystem around this component. Therefore, OSS adoption strategy models need to be structured in the way to explicitly describe the role of the adopter organization within the OSS ecosystem, which may be quite different depending on the level of compromise that the organization prefers. Making visible the roles played by the different agents involved in the OSS ecosystem, the involvement of the organization in the OSS community arises naturally. This paper includes a set of roles that emerge in an OSS ecosystem and their responsibilities, and describes the issues behind the fact of using the i* role and plays constructs.Postprint (author's final draft

Fostering the adoption of i* by practitioners: some challenges and research directions

The i* framework is a widespread formalism in the software engineering discipline that allows expressing intentionality of system actors. From the time it was issued, in the mid-nineties, a growing research community has adopted it either in its standard form or formulating variations in order to adapt it to some particular purpose. New methods, techniques and tools have made evolve the framework in a way that it may be currently considered quite mature from the scientific perspective. However, the i* framework has not been transferred to practitioners at the same extent yet: industrial experiences using i* are not many and have been mainly conducted by i* experts that are part of that very research community. Therefore, it may be argued that some steps are needed for boosting the adoption of i* by practitioners. In this chapter, we identify some scientific challenges whose overcoming could represent a step towards this goal. For each challenge, we present the problem that is addressed, its current state of the art and some envisaged lines of research.Preprin

Towards a framework for improving goal-oriented requirement models quality

Goal-orientation is a widespread and useful approach to Requirements Engineering. However, quality assessment frameworks focused on goal-oriented processes are either limited or remain on the theoretical side. Requirements quality initiatives range from simple metrics applicable to requirements documents, to general-purpose quality frameworks that include syntactic, semantic and pragmatic concerns. In some recent works, we have proposed a metrics framework for goal-oriented models, but the approach did not cover the cycle of quality assessment. In this paper we present a semiotic-based quality assessment proposal built upon the i* framework and the SEQUAL proposal. We propose a simplification of SEQUAL which can be applied to i* models by defining semantic, pragmatic and social metrics. As a result, we obtain suites of metrics that can be applied to i* goal-oriented requirements models. This theoretical work is put into practice by using iStarML, a XML representation of i* models, over which XQuery sentences compute the proposed metrics.Peer ReviewedPostprint (published version

Towards interoperability of i* models using iStarML

Goal-oriented and agent-oriented modelling provides an effective approach to the understanding of distributed information systems that need to operate in open, heterogeneous and evolving environments. Frameworks, firstly introduced more than ten years ago, have been extended along language variants, analysis methods and CASE tools, posing language semantics and tool interoperability issues. Among them, the i* framework is one the most widespread. We focus on i*-based modelling languages and tools and on the problem of supporting model exchange between them. In this paper, we introduce the i* interoperability problem and derive an XML interchange format, called iStarML, as a practical solution to this problem. We first discuss the main requirements for its definition, then we characterise the core concepts of i* and we detail the tags and options of the interchange format. We complete the presentation of iStarML showing some possible applications. Finally, a survey on the i* community perception about iStarML is included for assessment purposes.Preprin