Health Figures: An Open Source JavaScript Library for Health Data Visualization

The way we look at data has a great impact on how we can understand it, particularly when the data is related to health and wellness. Due to the increased use of self-tracking devices and the ongoing shift towards preventive medicine, better understanding of our health data is an important part of improving the general welfare of the citizens. Electronic Health Records, self-tracking devices and mobile applications provide a rich variety of data but it often becomes difficult to understand. We implemented the hFigures library inspired on the hGraph visualization with additional improvements. The purpose of the library is to provide a visual representation of the evolution of health measurements in a complete and useful manner. We researched the usefulness and usability of the library by building an application for health data visualization in a health coaching program. We performed a user evaluation with Heuristic Evaluation, Controlled User Testing and Usability Questionnaires. In the Heuristics Evaluation the average response was 6.3 out of 7 points and the Cognitive Walkthrough done by usability experts indicated no design or mismatch errors. In the CSUQ usability test the system obtained an average score of 6.13 out of 7, and in the ASQ usability test the overall satisfaction score was 6.64 out of 7. We developed hFigures, an open source library for visualizing a complete, accurate and normalized graphical representation of health data. The idea is based on the concept of the hGraph but it provides additional key features, including a comparison of multiple health measurements over time. We conducted a usability evaluation of the library as a key component of an application for health and wellness monitoring. The results indicate that the data visualization library was helpful in assisting users in understanding health data and its evolution over time.Comment: BMC Medical Informatics and Decision Making 16.1 (2016

Four approaches to teaching programming

Based on a survey of literature, four different approaches to teaching introductory programming are identified and described. Examples of the practice of each approach are identified representing procedural, visual, and object-oriented programming language paradigms. Each approach is then further analysed, identifying advantages and disadvantages for the student and the teacher. The first approach, code analysis, is analogous to reading before writing, that is, recognising the parts and what they mean. It requires learners to analyse and understand existing code prior to producing their own. An alternative is the building blocks approach, analogous to learning vocabulary, nouns and verbs, before constructing sentences. A third approach is identified as simple units in which learners master solutions to small problems before applying the learned logic to more complex problems. The final approach, full systems, is analogous to learning a foreign language by immersion whereby learners design a solution to a non-trivial problem and the programming concepts and language constructs are introduced only when the solution to the problem requires their application. The conclusion asserts that competency in programming cannot be achieved without mastering each of the approaches, at least to some extent. Use of the approaches in combination could provide novice programmers with the opportunities to acquire a full range of knowledge, understanding, and skills. Several orders for presenting the approaches in the classroom are proposed and analysed reflecting the needs of the learners and teachers. Further research is needed to better understand these and other approaches to teaching programming, not in terms of learner outcomes, but in terms of teachers’ actions and techniques employed to facilitate the construction of new knowledge by the learners. Effective classroom teaching practices could be informed by further investigations into the effect on progression of different toolset choices and combinations of teaching approache

The role of metaphor in user interface design

The thesis discusses the question of how unfamiliar computing systems, particularly those with graphical user interfaces, are learned and used. In particular, the approach of basing the design and behaviour of on-screen objects in the system's model world on a coherent theme and employing a metaphor is explored. The drawbacks, as well as the advantages, of this approach are reviewed and presented. The use of metaphors is also contrasted with other forms of users' mental models of interactive systems, and the need to provide a system image from which useful mental models can be developed is presented. Metaphors are placed in the context of users' understanding of interactive systems and novel application is made of the Qualitative Process Theory (QPT) qualitative reasoning model to reason about the behaviour of on-screen objects, the underlying system functionality, and the relationship between the two. This analysis supports reevaluation of the domains between which user interface metaphors are said to form mappings. A novel user interface design, entitled Medusa, that adopts guidelines for the design of metaphor-based systems, and for helping the user develop successful mental models, based on the QPT analysis and an empirical study of a popular metaphor-based system, is described. The first Medusa design is critiqued using well-founded usability inspection method. Employing the Lakoff/Johnson theory, a revised version of the Medusa user interface is described that derives its application semantics and dialogue structures from the entailments of the knowledge structures that ground understanding of the interface metaphor and that capture notions of embodiment in interaction with computing devices that QPT descriptions cannot. Design guidelines from influential existing work, and new methods of reasoning about metaphor-based designs, are presented with a number of novel graphical user interface designs intended to overcome the failings of existing systems and design approaches

Light-weight ontologies for scrutable user modelling

This thesis is concerned with the ways light-weight ontologies can support scrutability for large user models and the user modelling process. It explores the role that light-weight ontologies can play, and how they can be exploited, for the purpose of creating and maintaining large, scrutable user models consisting of hundreds of components. We address problems in four key areas: ontology creation, metadata annotation, creation and maintenance of large user models, and user model visualisation, with a goal to provide a simple and adaptable approach that maintains scrutability. Each of these key areas presents a number of challenges that we address. Our solution is the development of a toolkit, LOSUM, which consists of a number of tools to support the user modelling process. It incorporates light-weight ontologies to fulfill a number of roles: aiding in metadata creation, providing structure for large user model visualisation, and as a means to reason across granularities in the user model. In conjunction with this, LOSUM also features a novel visualisation tool, SIV, which performs a dual role of ontology and user model visualisation, supporting the process of ontology creation, metadata annotation, and user model visualisation. We evaluated our approach at each stage with small user studies, and conducted a large scale integrative evaluation of these approaches together in an authentic learning context with 114 students, of whom 77 had exposure to their learner models through SIV. The results showed that students could use the interface and understand the process of user model construction. The flexibility and adaptability of the toolkit has also been demonstrated in its deployment in several other application areas

Cognitive dimensions usability assessment of textual and visual VHDL environments

Visual programming languages promise to make programming easier with simpler graphical methods, broadening access to computing by lessening the need for would-be users to become proficient with textual programming languages, with their somewhat arcane grammars and methods removed from the problem space of the user. However, after more than forty years of research in the field, visual methods remain in the margins of use and programming remains the bailiwick of people devoted to the endeavor. VPL designers need to understand the mechanisms of usability that pertain to complex systems like programming language environments. Effective research tools for studying usability, and sufficiently constrained, mature subjects for investigation are scarce. This study applies a usability research tool, with its origins in applied psychology, to a programming language surrogate from the hardware description language class of notations. The substitution is reasonable because of the great similarity between hardware description languages and programming languages. Considering VHDL (the VHSIC Hardware Description Language) is especially worthwhile for several reasons, but primarily because significant numbers of digital designers regularly employ both textual and visual VHDL environments to meet the same real-world design challenges. A comparative analysis of Cognitive Dimensions assessments of textual and visual VHDL environments should further understanding of the usability issues specifically related to visual methods – in many cases, the same visual methods used in visual programming languages. Furthermore, with this real-world ‘field lab’ better understood, it should be possible to design experiments to pursue the formalization of the CDs framework as a theory

Reusable and Sharable Learning Objects Supporting Students’ Learning of Data Structures in University Courses

Data structures are a conceptually demanding topic which confronts many computer science students early in their course. The topic has a strong conceptual basis and often proves difficult for many to grasp. This paper reports on a project which has developed a range of learning objects to help students learn about the different data structures and the algorithms by which they are controlled. Called VIDSAA, the suite of learning objects provides a visual representation which enables students to observe and interact with a large number of data structure algorithms as they are run and to observe and view the outcomes. The objects have been designed to enable students to explore and investigate the data structures as a means of developing their knowledge and understanding. The paper describes the design and development strategies that underpinned the development of the learning objects and showcases the resulting products. It discusses a project to explore how teachers and students might use the objects and the support they provide for learning

Reusable and Sharable Learning Objects Supporting Students’ Learning of Data Structures in University Courses

Data structures are a conceptually demanding topic which confronts many computer science students early in their course. The topic has a strong conceptual basis and often proves difficult for many to grasp. This paper reports on a project which has developed a range of learning objects to help students learn about the different data structures and the algorithms by which they are controlled. Called VIDSAA, the suite of learning objects provides a visual representation which enables students to observe and interact with a large number of data structure algorithms as they are run and to observe and view the outcomes. The objects have been designed to enable students to explore and investigate the data structures as a means of developing their knowledge and understanding. The paper describes the design and development strategies that underpinned the development of the learning objects and showcases the resulting products. It discusses a project to explore how teachers and students might use the objects and the support they provide for learning