Dirk van der Linden

How Cognitively Effective is a Visual Notation? On the Inherent Difficulty of Operationalizing the Physics of Notations

The Physics of Notations [9] (PoN) is a design theory presenting nine principles that can be used to evaluate and improve the cognitive effectiveness of a visual notation. The PoN has been used to analyze existing standard visual notations (such as BPMN, UML, etc.), and is commonly used for evaluating newly introduced visual notations and their extensions. However, due to the rather vague and abstract formulation of the PoN’s principles, they have received different interpretations in their operationalization. To address this problem, there have been attempts to formalize the principles, however only a very limited number of principles was covered. This research-in-progress paper aims to better understand the difficulties inherent in operationalizing the PoN, and better separate aspects of PoN, which can potentially be formulated in mathematical terms from those grounded in user-specific considerations.

User Involvement in Applications of the PoN

In a previous paper [12] we argued for more user-centric analysis of modeling languages’ visual notation quality. Here we present initial findings from a systematic literature review on the use of the Physics of Notations (PoN) to further that argument. Concretely, we show that while the PoN is widely applied, these applications rarely actively involve intended users of a visual notation in setting the requirements for the notation, nor in evaluating its improvement or design according to the PoN’s criteria. We discuss the potential reasons for this lack of user involvement, and what can be gained from increasing user involvement.

Evaluating the Evaluators

This position paper presents the preliminary findings of a systematic literature review of applications of the Physics of Notations: a recently dominant framework for assessing the cognitive effectiveness of visual notations. We present our research structure in detail and discuss some initial findings, such as the kinds of notations the PoN has been applied to, whether its usage is justified and to what degree users are involved in eliciting requirements for the notation before its application. We conclude by summarizing and briefly discussing further analysis to be done and valorization of such results as guidelines for better application.

Pushing Boundaries of RE: Requirement Elicitation for Non-human Users

With the advance of modern technologies, computer-based systems for animals are gaining popularity. In particular, there is an explosion of products and gadgets for pets: wellness monitoring applications (e.g., FitBark and PetPace), automatic food dispensers, cognitive enrichment apps, and many more. Furthermore, the discipline of Animal-Computer Interaction has emerged, focusing on a user-centric development of technologies for animals, making them stakeholders in the development process. Animal-centric technologies have already been developed to support activities of rescue and assistance dogs, to provide environmental and cognitive enrichment for animals in captivity, and to support conservation and animal behavior research. Going beyond human stakeholders poses new exciting challenges for requirement engineering and can be used to significantly expand its boundaries under broader theoretical and methodological frameworks. This paper highlights these challenges and proposes a research agenda for developing methodologies for requirement elicitation and analysis for a user-centric development of computerized systems for non-human users.

A Framework for Improving the Verifiability of Visual Notation Design Grounded in the Physics of Notations

This paper proposes a systematic framework for applying the Physics of Notations (PoN), a theory for the design of cognitively effective visual notations. The PoN consists of nine principles, but not all principles lend themselves equally to a clear and unambiguous operationalization. As a result, many visual notations designed according to the PoN apply it in different ways. The proposed framework guides what information is required of a reported PoN application to ensure that the application of each principle is verifiable. The framework utilizes an evidence-driven design rationale model to structure information needed to assess principles requiring user involvement or cognitive theories. This approach aims to reduce ambiguity in some of the principles by making design choices explicit, and highlighting the level of evidence presented to support it. We demonstrate the proposed framework in a showcase of a recently published visual notation which has been designed with the PoN in mind.

Agile with Animals: Towards a Development Method

The advance of modern technologies opens new exciting opportunities for computer-based systems for animals. There is an explosion of products and gadgets for animals, such as wellness monitoring applications (e.g., FitBark and PetPace), automatic food dispensers, digital enrichment, and many more. The emerging discipline of Animal-Computer Interaction marks a new era in the development for non-human users, stressing a user-centric approach.As most available elicitation techniques in RE are verbal and little reusable requirements data yet exists, this calls for developing new approaches which can be adapted to non-human users. This paper takes a step in this direction by proposing a development model which incorporates iterative prototyping, animal welfare as a central value, and a direct involvement of animal experts at all stages of the development process.

Towards a Marketplace of Visual Elements for Notation Design

New visual languages and extensions of existing notations are increasingly introduced for various purposes. There are many frameworks and theories that aid designers in creating cognitively effective visual notations. They usually provide general guidelines, which are not easily operationalized without extensive user involvement. However, often such user involvement is difficult to achieve, especially in scientific settings where finding enough participants with the needed background knowledge is far from trivial. In this paper we propose the idea of creating a searchable marketplace of visual elements, in which designers could share and exchange elements of visual notations. A key feature of such marketplace would be the ability to certify such elements via procedures grounded in empirical research. We discuss a proposed structure of the marketplace, and the challenge that the need for certification poses to its design.

What practitioners really want: requirements for visual notations in conceptual modeling

This research was aimed at eliciting the requirements of practitioners who use conceptual modeling in their professional work for the visual notations of modeling languages. While the use of conceptual modeling in practice has been addressed, what practitioners in fact require of the visual notation of the modeling languages they use has received little attention. This work was thus motivated by the need to understand to what extent practitioners’ requirements are acknowledged and accommodated by visual notation research efforts. A mixed-method study was conducted, with a survey being offered over the course of several months to LinkedIn professional groups. The requirements included in the survey were based on a leading design theory for visual notations, the Physics of Notations. After preprocessing, 104 participant responses were analyzed. Data analysis included descriptive coding and qualitative analysis of purposes for modeling and additional requirements beyond the scope of visual design. Statistical and factorial analysis was used to explore potential correlations between the importance of different requirements as perceived by practitioners and the demographic factors (e.g., domain, purpose, topics). The results indicate several correlations between demographic factors and the perceived importance of visual notation requirements, as well as differences in the perceived relative importance of different requirements for models used to communicate with modeling experts as compared to non-experts. Furthermore, the results show an evolution from trends identified in studies conducted in the previous decade. The identified correlations with practitioners’ demographics reveal several research challenges that should be addressed, as well as the potential benefits of more purpose-specific tailoring of visual notation design. Furthermore, the shift in practitioner demographics as compared to those found in earlier work indicates that the research and development of conceptual modeling efforts needs to stay up-to-date with the way practitioners employ conceptual modeling.

K9-Blyzer: Towards Video-Based Automatic Analysis of Canine Behavior

Automatic analysis of animal behavior has the potential to revolutionize the work of animal science and ACI researchers. Many tracking and behavior analysis systems exist for different species, such as birds, insects and mice, but behavior analysis in the canine domain still remains a challenging task. In this research-in-progress paper we describe K9-Blyzer (Canine Behavior Analyzer), which is a tool for automatic video analysis of canine behavior. We present preliminary results of automatic analysis of dog-robot interactions, point out some envisioned extensions of the tool and discuss the potential applications of the tool for the field of ACI.

On the Requirement from Practice for Meaningful Variability in Visual Notation

This research-in-progress paper proposes the need for a move towards more meaningful variability of visual notations. Evidence accumulated via an online survey on the requirements practitioners have for visual notations, indicate the need for variability of a modeling language’s visual notation. Widely used modeling languages in practice such as UML and BPMN do not support redesign of the visual notation of core constructs without modifying or extending the underlying abstract syntax and semantics (e.g., UML stereotypes, BPMN extensions). The expressed need to vary commonly used visual notations depending on particular users or contexts, while not changing the underlying modeling language itself, poses a set of research challenges discussed here.