A visual exploration workflow as enabler for the exploitation of Linked Open Data

Abstract. Semantically annotating and interlinking Open Data results in Linked Open Data which concisely and unambiguously describes a knowledge domain. However, the uptake of the Linked Data depends on its usefulness to non-Semantic Web experts. Failing to support data consumers to understand the added-value of Linked Data and possible exploitation opportunities could inhibit its diffusion. In this paper, we propose an interactive visual workflow for discovering and ex-ploring Linked Open Data. We implemented the workflow considering academic library metadata and carried out a qualitative evaluation. We assessed the work-flow’s potential impact on data consumers which bridges the offer: published Linked Open Data; and the demand as requests for: (i) higher quality data; and (ii) more applications that re-use data. More than 70 % of the 34 test users agreed that the workflow fulfills its goal: it facilitates non-Semantic Web experts to un-derstand the potential of Linked Open Data.

Multi Visualization and Dynamic Query for Effective Exploration of Semantic Data

Semantic formalisms represent content in a uniform way according to ontologies. This enables manipulation and reasoning via automated means (e.g. Semantic Web services), but limits the user’s ability to explore the semantic data from a point of view that originates from knowledge representation motivations. We show how, for user consumption, a visualization of semantic data according to some easily graspable dimensions (e.g. space and time) provides effective sense-making of data. In this paper, we look holistically at the interaction between users and semantic data, and propose multiple visualization strategies and dynamic filters to support the exploration of semantic-rich data. We discuss a user evaluation and how interaction challenges could be overcome to create an effective user-centred framework for the visualization and manipulation of semantic data. The approach has been implemented and evaluated on a real company archive

A framework for the design of business intelligence dashboard tools

Vast amounts of data are collected on a daily basis, making it difficult for humans to derive at valuable information to make effective decisions. In recent years, the field of Business Intelligence (BI) and Information Visualisation (IV) have become a key driver of an organisation’s success. BI tools supporting decision making need to be accessible to a larger audience on different levels of the organisation. The problem is that non-expert users, or novice users, of BI tools do not have the technical knowledge to conduct data analysis and often rely on expert users to assist. For this reason, BI vendors are shifting their focus to self-service BI, a relatively new term where novice users can analyse data without the traditional human mediator. Despite the proliferation of self-service BI tools, limited research is available on their usability and design considerations to assist novice users with decision making and BI analysis. The contribution of this study is a conceptual framework for designing, evaluating or selecting BI tools that support non-expert users to create dashboards (the BI Framework). A dashboard is a particular IV technique that enables users to view critical information at a glance. The main research problem addressed by this study is that non-expert users often have to utilise a number of software tools to conduct data analysis and to develop visualisations, such as BI dashboards. The research problem was further investigated by following a two-step approach. The first approach was to investigate existing problems by using an in-depth literature review in the fields of BI and IV. The second approach was to conduct a field study (Field Study 1) using a development environment consisting of a number of software components of which SAP Xcelsius was the main BI tool used to create a dashboard. The aim of the field study was to compare the identified problems and requirements with those found in literature. The results of the problem analysis revealed a number of problems in terms of BI software. One of the major problems is that BI tools do not adequately guide users through a logical process to conduct data analysis. In addition, the process becomes increasingly difficult when several BI tools are involved that need to be integrated. The results showed positive aspects when the data was mapped to a visualisation, which increased the users’ understanding of data they were analysing. The results were verified in a focus group discussion and were used to establish an initial set of problems and requirements, which were then synthesised with the problems and requirements identified from literature. Once the major problems were verified, a framework was established to guide the design of BI dashboard tools for novice users. The framework includes a set of design guidelines and usability evaluation criteria for BI tools. An extant systems analysis was conducted using BI tools to compare the advantages and disadvantages. The results revealed that a number of tools could be used by non-experts, however, their usability hinders users. All the participants used in all field studies and evaluations were Computer Science (CS) and Information Systems (IS) students. Participants were specially sourced from a higher education institution such as the Nelson Mandela Metropolitan University (NMMU). A second field study (Field Study 2) was conducted with participants using another traditional BI tool identified from the extant systems analysis, PowerPivot. The objective of this field study was to verify the design guidelines and related features that served as a BI Scorecard that can be used to select BI tools. Another BI tool, Tableau, was used for the final evaluation. The final evaluation was conducted with a large participant sample consisting of IS students in their second and third year of study. The results for the two groups revealed a significant difference between participants’ education levels and the usability ratings of Tableau. Additionally, the results indicated a significant relationship between the participants’ experience level and the usability ratings of Tableau. The usability ratings of Tableau were mostly positive and the results revealed that participants found the tool easy to use, flexible and efficient. The proposed BI Framework can be used to assist organisations when evaluating BI tools for adoption. Furthermore, designers of BI tools can use the framework to improve the usability of these tools, reduce the workload for users when creating dashboards, and increase the effectiveness and efficiency of decision support

Uvis: A Formula-Based End-User Tool for Data Visualization

© 2013 IEEE. Existing approaches to data visualization are one of these two: accessible to end-user developers but limited in customizability, or inaccessible and expressive. For instance, commercial charting tools are easy to use, but support only predefined visualizations, while programmatic visualization tools support custom visualizations, but require advanced programming skills. We show that it is possible to combine the learnability of charting tools and the expressiveness of visualization tools. Uvis is an interactive visualization and user interface design tool that targets end-user developers with skills comparable to spreadsheet formulas. With Uvis, designers drag and drop visual objects, set visual properties to formulas, and see the result immediately. The formulas are declarative and similar to spreadsheet formulas. The formulas compute the property values and can refer to data from database, visual objects, and end-user input. To substantiate our claim, we compared Uvis with popular visualization tools. Further, we conducted usability studies that test the ability of designers to customize visualizations with our approach. Our results show that end-user developers can learn the basics of Uvis relatively fast

Stacking-based visualization of trajectory attribute data

Visualizing trajectory attribute data is challenging because it involves showing the trajectories in their spatio-temporal context as well as the attribute values associated with the individual points of trajectories. Previous work on trajectory visualization addresses selected aspects of this problem, but not all of them. We present a novel approach to visualizing trajectory attribute data. Our solution covers space, time, and attribute values. Based on an analysis of relevant visualization tasks, we designed the visualization solution around the principle of stacking trajectory bands. The core of our approach is a hybrid 2D/3D display. A 2D map serves as a reference for the spatial context, and the trajectories are visualized as stacked 3D trajectory bands along which attribute values are encoded by color. Time is integrated through appropriate ordering of bands and through a dynamic query mechanism that feeds temporally aggregated information to a circular time display. An additional 2D time graph shows temporal information in full detail by stacking 2D trajectory bands. Our solution is equipped with analytical and interactive mechanisms for selecting and ordering of trajectories, and adjusting the color mapping, as well as coordinated highlighting and dedicated 3D navigation. We demonstrate the usefulness of our novel visualization by three examples related to radiation surveillance, traffic analysis, and maritime navigation. User feedback obtained in a small experiment indicates that our hybrid 2D/3D solution can be operated quite well

Unfolding -- A library for interactive maps

Visualizing data with geo-spatial properties has become more important and prevalent due to the wide spread dissemination of devices, sensors, databases, and services with references to the physical world. Yet, with existing tools it is often difficult to create interactive geovisualizations tailored for a particular domain or a specific dataset. We present Unfolding, a library for interactive maps and data visualization. Unfolding provides an API for designers to quickly create and customize geo-visualizations. In this paper, we describe the design criteria, the development process, and the functionalities of Unfolding. We demonstrate its versatility in use through a collection of examples. Results from a user survey suggests programmers find the library easy to learn and to use

TRANSLATING VISUALIZATION INTERACTION INTO NATURAL LANGUAGE

Richly interactive visualization tools are increasingly popular for data exploration and analysis in a wide variety of domains. Recent advancements in data collection and storage call for more complex analytical tasks to make sense of readily available datasets. More complicated and sophisticated tools are needed to complete those tasks. However, as these visualization tools get more complicated, it becomes increasingly difficult to learn interaction sequences, recall past queries asked from a visualization, and correctly interpret visual states to forage the data. Moreover, the high interactivity of such tools increases the challenge of connecting low-level acquired information to higher-level analytical questions and hypotheses to support, reason, and eventually present insights. This makes studying the usability of complex interactive visualizations, both in the process of foraging and making sense of data, an essential part of visual analytic research. This research can be approached in at least two major ways. One can focus on studying new techniques and guidelines for designing interactive complex visualizations that are easy to use and understand. One can also focus on keeping the capabilities of existing complex visualizations, yet provide supporting capabilities that increases their usability. The latter is an emerging area of research in visual analytics, and is the focus of this dissertation. This dissertation describes six contributions to the field of visual analytics. The first contribution is an architecture of a query-to-question supporting system that automatically records user interactions and presents them contextually using natural written language. The architecture takes into account the domain knowledge of experts/designers and uses natural language generation (NLG) techniques to translate and transcribe a progression of interactive visualization states into a log of text that can be visualized. The second contribution is query-to-question (Q2Q), an implemented system that translates low-level user interactions into high-level analytical questions and presents them as a log of styled text that complements and effectively extends the functionality of visualization tools. The third contribution is a demonstration of the beneficial effects of accompanying a visualization with a textual translation of user interaction on the usability of visualizations. The presence of the translation interface produces considerable improvements in learnability, efficiency, and memorability of visualization in terms of speed and the length of interaction sequences that users perform, along with a modest decrease in error ratio. The fourth contribution is a set of design guidelines for translating user interactions into natural language, taking into account variation in user knowledge and roles, the types of data being visualized, and the types of interaction supported. The fifth contribution is a history organizer interface that enables users to organize their analytical process. The structured textual translations output from Q2Q are input into a history organizer tool (HOT) that imposes reordering, sequencing, and grouping of the translated interactions. HOT provides a reasoning framework for users to organize and present hypotheses and insight acquired from a visualization. The sixth contribution is a demonstration of the efficiency of a suite of arrangement options for organizing questions asked in a visualization. Integration of query translation and history organization improves users' speed, error ratio, and number of reordering actions performed during organization of translated interactions. Overall, this dissertation contributes to the analysis and discovery of user storytelling patterns and behaviours, thereby paving the way to the creation of more intelligent, effective, and user-oriented visual analysis presentation tools

A framework for the design of business intelligence dashboard tools

Vast amounts of data are collected on a daily basis, making it difficult for humans to derive at valuable information to make effective decisions. In recent years, the field of Business Intelligence (BI) and Information Visualisation (IV) have become a key driver of an organisation’s success. BI tools supporting decision making need to be accessible to a larger audience on different levels of the organisation. The problem is that non-expert users, or novice users, of BI tools do not have the technical knowledge to conduct data analysis and often rely on expert users to assist. For this reason, BI vendors are shifting their focus to self-service BI, a relatively new term where novice users can analyse data without the traditional human mediator. Despite the proliferation of self-service BI tools, limited research is available on their usability and design considerations to assist novice users with decision making and BI analysis. The contribution of this study is a conceptual framework for designing, evaluating or selecting BI tools that support non-expert users to create dashboards (the BI Framework). A dashboard is a particular IV technique that enables users to view critical information at a glance. The main research problem addressed by this study is that non-expert users often have to utilise a number of software tools to conduct data analysis and to develop visualisations, such as BI dashboards. The research problem was further investigated by following a two-step approach. The first approach was to investigate existing problems by using an in-depth literature review in the fields of BI and IV. The second approach was to conduct a field study (Field Study 1) using a development environment consisting of a number of software components of which SAP Xcelsius was the main BI tool used to create a dashboard. The aim of the field study was to compare the identified problems and requirements with those found in literature. The results of the problem analysis revealed a number of problems in terms of BI software. One of the major problems is that BI tools do not adequately guide users through a logical process to conduct data analysis. In addition, the process becomes increasingly difficult when several BI tools are involved that need to be integrated. The results showed positive aspects when the data was mapped to a visualisation, which increased the users’ understanding of data they were analysing. The results were verified in a focus group discussion and were used to establish an initial set of problems and requirements, which were then synthesised with the problems and requirements identified from literature. Once the major problems were verified, a framework was established to guide the design of BI dashboard tools for novice users. The framework includes a set of design guidelines and usability evaluation criteria for BI tools. An extant systems analysis was conducted using BI tools to compare the advantages and disadvantages. The results revealed that a number of tools could be used by non-experts, however, their usability hinders users. All the participants used in all field studies and evaluations were Computer Science (CS) and Information Systems (IS) students. Participants were specially sourced from a higher education institution such as the Nelson Mandela Metropolitan University (NMMU). A second field study (Field Study 2) was conducted with participants using another traditional BI tool identified from the extant systems analysis, PowerPivot. The objective of this field study was to verify the design guidelines and related features that served as a BI Scorecard that can be used to select BI tools. Another BI tool, Tableau, was used for the final evaluation. The final evaluation was conducted with a large participant sample consisting of IS students in their second and third year of study. The results for the two groups revealed a significant difference between participants’ education levels and the usability ratings of Tableau. Additionally, the results indicated a significant relationship between the participants’ experience level and the usability ratings of Tableau. The usability ratings of Tableau were mostly positive and the results revealed that participants found the tool easy to use, flexible and efficient. The proposed BI Framework can be used to assist organisations when evaluating BI tools for adoption. Furthermore, designers of BI tools can use the framework to improve the usability of these tools, reduce the workload for users when creating dashboards, and increase the effectiveness and efficiency of decision support

Visualization of Guidelines on Computer Networks to Support Processes of Design and Quality Control

Industrial companies supply products intended to satisfy customers’ needs and requirements. To be competitive and to maintain good economic performance, efficient systems are needed to communicate information and exchange knowledge. Such systems are often referred to as quality systems as they intend to support development as well as standardized work regarding the quality of the product and increase satisfaction of the company’s customers and other stakeholders (employees, owners, sub-suppliers, society). Many companies try to structure and improve their quality systems by applying the international quality standard ISO 9000, which can result in extensive documentation. The guidelines and instructions of quality management systems are traditionally documented and presented as paper documents, alternatively on an intranet (a company’s internal computer network) suitable for printouts. These however, do not correspond to some company’s requirements for usability in daily work and as support to interest and engage the personnel in development work. An assumption was that visualizing guidelines using different kinds of multimedia technologies such as hyperlinked and animated pictorial illustrations might be relevant to support quality control and design processes in industrial companies. Two objectives were set up: The first was to explore how the usability of guidelines could be improved by changing the interface design of the guidelines; The second was to explore how the visualization process of guidelines could support participative design by applying evaluations and interpretations in a dialogue form between two individuals or among a group of individuals. The methodology that has been used to generate research questions as well as methods is based on theories of action research and experiential learning. Various methods have been used and combined in order to collect information and to ensure the reliability of the findings based on it. Three industrial companies participated in a first case study. They had conventional quality systems, which they wanted to replace or improve. The companies set up design teams to establish principles for visualizations of their quality systems on their intranets. Cooperating with the author, the design teams created and evaluated computer supported prototypes. These prototypes were made available via the Internet and discussed within each design team. The teams exchanged ideas and comments to enhance their prototypes. The results showed that a quality system should be visualized by an overview of the physical production plant. Information about different processes and instructions are represented by hyperlinked symbols within or next to the plant layout. A second field study aimed to clarify how industrial companies with certified quality systems according to ISO 9001 visualized their guidelines and instructions of construction, production, and installation. The quality manager at each company evaluated the existing system and explained their needs of developing the system by means of computer supported visualization on their intranet. The information was collected through telephone interviews and on site visits. The results showed that the companies would like to improve the visualization of information by decreasing text and increasing pictorial descriptions, such as flowcharts and animations. They also experienced that a quality system on the companies’ intranets was or should be an enhancement in order to disseminate and update the information. A third case study performed in collaboration with Saab Automobile showed results that corresponded with the other studies. The company wanted to replace their conventional information system of ergonomic design guidelines for cars, and design a new system based on interactivity and multimedia. The results showed that a pictorial overview of the car with different areas hyperlinked to further information was preferred. The specific information in the ergonomic guidelines was illustrated with icons, pictures, animations, and some text. In a comparison with the conventional system, subjects performed working tasks faster and with a more positive attitude in the new system. A fourth case study was performed within the GM company group, which showed the need of a formalized working process throughout work with human simulation tools as well as possibilities to document the information generated. A human simulation system prototype was modeled in collaboration with the companies and was presented on an intranet. The results indicated a great potential to enhance the communication within and between the companies, increased accessibility to knowledge, and increased quality on performed work. To summarize, the studies in this thesis show a need among industrial companies to visualize guidelines in information and quality systems by means of multimedia and an interactive design process. Such an approach supports knowledge acquisition and communication, and has a potential to ensure high quality in a company’s processes and products. Furthermore, the users’ attitudes tend to become more positive to the information presented compared to a conventional system