We present the Critical Design Strategy (CDS)-a structured method designed to facilitate the examination of visualisation designs through reflection and critical thought. The CDS helps designers think critically and make informed improvements using heuristic evaluation. When developing a visual tool or pioneering a novel visualisation approach, identifying areas for enhancement can be challenging. Critical thinking is particularly crucial for visualisation designers and tool developers, especially those new to the field, such as studying visualisation in higher education. The CDS consists of three stages across six perspectives: Stage 1 captures the essence of the idea by assigning an indicative title and selecting five adjectives (from twenty options) to form initial impressions of the design. Stage 2 involves an in-depth critique using 30 heuristic questions spanning six key perspectives-user, environment, interface, components, design, and visual marks. Stage 3 focuses on synthesising insights, reflecting on design decisions, and determining the next steps forward. We introduce the CDS and explore its use across three visualisation modules in both undergraduate and postgraduate courses. Our longstanding experience with the CDS has allowed us to refine and develop it over time: from its initial creation through workshops in 2017/18 to improvements in wording and the development of two applications by 2020, followed by the expansion of support notes and refinement of heuristics through 2023; while using it in our teaching each year. This sustained use allows us to reflect on its practical application and offer guidance on how others can incorporate it into their own work.

We introduce an authentic learning task, where students create data art visualisations from selected datasets to be showcased in a public exhibition. Our vision is to explore how creativity and visualisation intersect and how combining these elements results in an authentic learning task for computing students. Run over two completed academic years, with a third cohort nearing completion, this initiative offered an active learning environment that fostered student engagement, creativity, and the application of practical skills. We detail the structured approach, outlining eight steps that students perform: topic selection and research, data analysis, researching artistic inspiration, conceptualising designs, proposing solutions, creating visualisations, reflection and curating an exhibition. Our framework equips educators with detailed lectures and activities, enabling them to implement similar tasks in their own teaching. Finally, we present illustrative examples of student outcomes and share reflective insights, showcasing the impact of integrating authentic learning with public-facing creative projects. This approach enhances technical skills while connecting academic learning to real-world professional practice.

We present a path-based design model and system for designing and creating visualisations. Our model represents a systematic approach to constructing visual representations of data or concepts following a predefined sequence of steps. The initial step involves outlining the overall appearance of the visualisation by creating a skeleton structure, referred to as a flowpath. Subsequently, we specify objects, visual marks, properties, and appearance, storing them in a gene. Lastly, we map data onto the flowpath, ensuring suitable morphisms. Alternative designs are created by exchanging values in the gene. For example, designs that share similar traits, are created by making small incremental changes to the gene. Our design methodology fosters the generation of diverse creative concepts, space-filling visualisations, and traditional formats like bar charts, circular plots and pie charts. Through our implementation we showcase the model in action. As an example application, we integrate the output visualisations onto a smartwatch and visualisation dashboards. In this article we (1) introduce, define and explain the path model and discuss possibilities for its use, (2) present our implementation, results, and evaluation, and (3) demonstrate and evaluate an application of its use on a mobile watch.

This paper is a call to action for research and discussion on data visualization education. As visualization evolves and spreads through our professional and personal lives, we need to understand how to support and empower a broad and diverse community of learners in visualization. Data Visualization is a diverse and dynamic discipline that combines knowledge from different fields, is tailored to suit diverse audiences and contexts, and frequently incorporates tacit knowledge. This complex nature leads to a series of interrelated challenges for data visualization education. Driven by a lack of consolidated knowledge, overview, and orientation for visualization education, the 21 authors of this paper-educators and researchers in data visualization-identify and describe 19 challenges informed by our collective practical experience. We organize these challenges around seven themes People, Goals & Assessment, Environment, Motivation, Methods, Materials, and Change. Across these themes, we formulate 43 research questions to address these challenges. As part of our call to action, we then conclude with 5 cross-cutting opportunities and respective action items: embrace DIVERSITY+INCLUSION, build COMMUNITIES, conduct RESEARCH, act AGILE, and relish RESPONSIBILITY. We aim to inspire researchers, educators and learners to drive visualization education forward and discuss why, how, who and where we educate, as we learn to use visualization to address challenges across many scales and many domains in a rapidly changing world: viseducationchallenges.github.io.

Administrative justice concerns the relationships between individuals and the state. It includes redress and complaints on decisions of a child's education, social care, licensing, planning, environment, housing and homelessness. However, if someone has a complaint or an issue, it is challenging for people to understand different possible redress paths and explore what path is suitable for their situation. Explanatory visualisation has the potential to display these paths of redress in a clear way, such that people can see, understand and explore their options. The visualisation challenge is further complicated because information is spread across many documents, laws, guidance and policies and requires judicial interpretation. Consequently, there is not a single database of paths of redress. In this work we present how we have co-designed a system to visualise administrative justice paths of redress. Simultaneously, we classify, collate and organise the underpinning data, from expert workshops, heuristic evaluation and expert critical reflection. We make four contributions: (i) an application design study of the explanatory visualisation tool (Artemus), (ii) coordinated and co-design approach to aggregating the data, (iii) two in-depth case studies in housing and education demonstrating explanatory paths of redress in administrative law, and (iv) reflections on the expert co-design process and expert data gathering and explanatory visualisation for administrative justice and law.

Multiple-view visualization (MV) is a layout design technique often employed to help users see a large number of data attributes and values in a single cohesive representation. Because of its generalizability, the MV design has been widely adopted by the visualization community to help users examine and interact with large, complex, and high-dimensional data. However, although ubiquitous, there has been little work to categorize and analyze MVs in order to better understand its design space. As a result, there has been little to no guideline in how to use the MV design effectively. In this paper, we present an in-depth study of how MVs are designed in practice. We focus on two fundamental measures of multiple-view patterns: composition, which quantifies what view types and how many are there; and configuration, which characterizes spatial arrangement of view layouts in the display space. We build a new dataset containing 360 images of MVs collected from IEEE VIS, EuroVis, and PacificVis publications 2011 to 2019, and make fine-grained annotations of view types and layouts for these visualization images. From this data we conduct composition and configuration analyses using quantitative metrics of term frequency and layout topology. We identify common practices around MVs, including relationship of view types, popular view layouts, and correlation between view types and layouts. We combine the findings into a MV recommendation system, providing interactive tools to explore the design space, and support example-based design.

Abstract We report on an in‐depth corpus linguistic study on ‘multiple views’ terminology and word collocation. We take a broad interpretation of these terms, and explore the meaning and diversity of their use in visualisation literature. First we explore senses of the term ‘multiple views’ (e.g., ‘multiple views’ can mean juxtaposition, many viewport projections or several alternative opinions). Second, we investigate term popularity and frequency of occurrences, investigating usage of ‘multiple’ and ‘view’ (e.g., multiple views, multiple visualisations, multiple sets). Third, we investigate word collocations and terms that have a similar sense (e.g., multiple views, side‐by‐side, small multiples). We built and used several corpora, including a 6‐million‐word corpus of all IEEE Visualisation conference articles published in IEEE Transactions on Visualisation and Computer Graphics 2012 to 2017. We draw on our substantial experience from early work in coordinated and multiple views, and with collocation analysis develop several lists of terms. This research provides insight into term use, a reference for novice and expert authors in visualisation, and contributes a taxonomy of ‘multiple view’ terms.

Visualizations are nowadays appearing in popular media and are used everyday in the workplace. This democratisation of visualization challenges educators to develop effective learning strategies, in order to train the next generation of creative visualization specialists. There is high demand for skilled individuals who can analyse a problem, consider alternative designs, develop new visualizations, and be creative and innovative. Our three-stage framework, leads the learner through a series of tasks, each designed to develop different skills necessary for coming up with creative, innovative, effective, and purposeful visualizations. For that, we get the learners to create an explanatory visualization of an algorithm of their choice. By making an algorithm choice, and by following an active-learning and project-based strategy, the learners take ownership of a particular visualization challenge. They become enthusiastic to develop good results and learn different creative skills on their learning journey.

Sketching designs has been shown to be a useful way of planning and considering alternative solutions. The use of lo-fidelity prototyping, especially paper-based sketching, can save time, money and converge to better solutions more quickly. However, this design process is often viewed to be too informal. Consequently users do not know how to manage their thoughts and ideas (to first think divergently, to then finally converge on a suitable solution). We present the Five Design Sheet (FdS) methodology. The methodology enables users to create information visualization interfaces through lo-fidelity methods. Users sketch and plan their ideas, helping them express different possibilities, think through these ideas to consider their potential effectiveness as solutions to the task (sheet 1); they create three principle designs (sheets 2,3 and 4); before converging on a final realization design that can then be implemented (sheet 5). In this article, we present (i) a review of the use of sketching as a planning method for visualization and the benefits of sketching, (ii) a detailed description of the Five Design Sheet (FdS) methodology, and (iii) an evaluation of the FdS using the System Usability Scale, along with a case-study of its use in industry and experience of its use in teaching.

One of the goals of network administrators is to identify and block sources of attacks from a network steam. Various tools have been developed to help the administrator identify the IP or subnet to be blocked, however these tend to be non-visual. Having a good perception of the wider network can aid the administrator identify their origin, but while network maps of the Internet can be useful for such endeavors, they are difficult to construct, comprehend and even utilize in an attack, and are often referred to as being “hairballs”. We present a visualization technique that displays pathways back to the attacker; we include all potential routing paths with a best-efforts identification of the commercial relationships involved. These two techniques can potentially highlight common pathways and/or networks to allow faster, more complete resolution to the incident, as well as fragile or incomplete routing pathways to/from a network. They can help administrators re-profile their choice of IP transit suppliers to better serve a target audience.

With the rise of digital content and web-based technologies, archaeologists and heritage organisations are increasingly striving to produce digital records of archaeology and heritage sites. The large numbers and geographical spread of these sites means that it would be too time-consuming for any one team to survey them. To meet this challenge, the Heritage Together project has developed a web platform through which members of the public can upload their own photographs of heritage assets to be processed into 3D models using an automated photogrammetry work flow. The web platform is part of a larger project which aims to capture, create and archive digital heritage assets in conjunction with local communities in Wales, UK, with a focus on megalithic monuments. Heritage Together is a digital community and community-built archive of heritage data, developed to inspire local communities to learn more about their heritage and to help to preserve it.

Parallel coordinates are a well-known and valuable technique for the analysis and visualization of high dimen-sional data sets. However, while Inselberg emphasizes that the strength of parallel coordinates as a methodology is rooted in exploration and interactivity, the set of interac-tion techniques is currently limited. Axes can be re-ordered and brushing (simple, angular or multi-dimensional) can be performed. In this paper, we propose a force-directed algorithm and related interaction techniques to support the exploration of parallel coordinate plots through a physi-cal metaphor. Our parallel-coordinates visualization of-fers novel user interaction beyond the standard techniques by allowing the user to rotate the axis according to force-directed polylines. The new interaction provides the user with a more immersive experience for data exploration that results in greater intuition of the data, especially in cases where many polylines overlap. We demonstrate our ap-proach, then present the results of a qualitative evaluation of the system. 1

As international businesses adopt social media and virtual worlds as mediums for conducting international business, so there is an increasing need for interpreters who can bridge the language barriers, and work within these new spheres. The recent rise in migration (within the EU) has also increased the need for professional interpreters in business, legal, medical and other settings. Project IVY attempts to provide bespoke 3D virtual environments that are tailor made to train interpreters to work in the new digital environments, responding to this increased demand. In this paper we present the design and development of the IVY Virtual Environment. We present past and current design strategies, our implementation progress and our future plans for further development.

Abstract Close collaboration with other scientific fields is an important goal for the visualization community. Yet engaging in a scientific collaboration can be challenging. The physical sciences, namely astronomy, chemistry, earth sciences and physics, exhibit an extensive range of research directions, providing exciting challenges for visualization scientists and creating ample possibilities for collaboration. We present the first survey of its kind that provides a comprehensive view of existing work on visualization for the physical sciences. We introduce novel classification schemes based on application area, data dimensionality and main challenge addressed, and apply these classifications to each contribution from the literature. Our survey helps in understanding the status of current research and serves as a useful starting point for those interested in visualization for the physical sciences.

Parallel coordinates is a popular and well-known multivariate data visualization technique. However, one of their inherent limitations has to do with the rendering of very large data sets. This often causes an overplotting problem and the goal of the visual information seeking mantra is hampered because of a cluttered overview and non-interactive update rates. In this paper, we propose two novel solutions, namely, angular histograms and attribute curves. These techniques are frequency-based approaches to large, high-dimensional data visualization. They are able to convey both the density of underlying polylines and their slopes. Angular histogram and attribute curves offer an intuitive way for the user to explore the clustering, linear correlations and outliers in large data sets without the over-plotting and clutter problems associated with traditional parallel coordinates. We demonstrate the results on a wide variety of data sets including real-world, high-dimensional biological data. Finally, we compare our methods with the other popular frequency-based algorithms.

Studies show that roughly one-third of searches that are performed on the Web require the user to initiate subsequent searches. Bates theorized that with every search the user will encounter new information, which in turn leads to new ideas and directions. This process causes a change, not simply in the query terms being used but also to the nature of the information retrieval task itself; Bates called this the evolving search. She also noted that evolving searches utilize many different information sources, generate substantial quantities of data and require easy methods to save and recall data. Although current search tools are exceptionally efficient at locating highly ranked pages, the tools do not encourage or support the user in an evolving search. In this paper we present techniques that aid users to find, view and manage data produced from their evolving searches. In particular, we introduce the EvoBerry environment, which we have developed for use with evolving searches. EvoBerry includes methods to visualize additional search result information (such as length of page or file type), manage the user's session and browsing history, compare result sets, and store and bookmark items for future reference.

Brushing is a collection of techniques to dynamically query and directly select elements on the visual display. Such interaction allows the user to explore the visualization, to interactively select a subset of points and see how these changes are updated in other related views. Traditionally, the artefacts that are 'brushed' are the plotted elements in the visualization (e.g. the points on a scatter-plot, or the bars of a bar chart). In this paper, we discuss the concept of ubiquitous brushing (UB), which brings together various different types of selection (whether in data space, screen space or views). Not only can users brush over elements in the display but also they can brush over various meta-information such as menus, legends or axis to affect the highlighted elements. The paper discusses the basic idea and demonstrates how subsequent UB operations can be compound together to provide useful dynamic filter operations

There are many tools that provide the user with an abundance of sliders, buttons and options to change; such tools are popular in exploratory visualization. As the user changes the parameters so the display dynamically updates and responds appropriately to changes made. These multiparameter systems can be difficult to use, as the user is often unaware of the outcome of any action before it occurs. Specifically it may be unclear whether to increase or decrease a parameter value to get a desired result. Multiple view systems can help, as the user can try out various scenarios and compare the results side-by-side, although if unrestricted the user may be swamped by numerous and often unnecessary views. In this paper we present the novel idea of 'bracketing', where a principal view is supported with two additional views from slightly different parameterizations. The idea is inspired by exposure bracketing in photography. This provides a middle ground: it offers a way to see adjacent-parameterizations, while allowing yet restraining multiple views. Moreover, we demonstrate how bracketing can be exploited in many applications and used in various ways (within parameter, visual and temporal domains).

Recently researchers have been interested in non-visual forms of presentation. Sound, touch, smell, as well as vision can be used to depict information. One important medium is sound; it can encode information for the blind or partial sighted, used to display information when it is impossible to use a screen, and the hardware is cheap and widely available. Researchers have investigated sonifying various data sources with different data types and configurations. We present a novel path-based model that can be used to describe each of these different sonifications. In summary, the path dictates the sonification tour, the data is mapped into sound via a transfer function, and the quantity of information being sonified is determined by both the span and how the abstract path is registered to the data.

When searching on the Web, users often reformulate their queries after viewing the results and viewing some of the pages. After one or two reformulations the user may implicitly realize patterns and relationships between the multiple search results. We believe that these patterns can be used to identify interesting results. We have developed the prototype Search Engine Similarity (SES) tool which explicitly visualizes the similarity between multiple searches. We describe an experiment to determine whether explicitly visualizing the relationships between multiple searches will let users browse more effectively. Our results show that explicit difference visualizations can enhance the search process for some tasks.

Different acoustic variables such as pitch, volume, timbre and position can be used to represent quantitative, qualitative and categorical aspects of the information. Such sonifications are particularly useful for those with visual impairments; they are also beneficial in circumstances where visual representations would be impossible to use or to enrich a graphical realization. We demonstrate methods of representing an audible pie chart representation such that the hearer understands the information through an equivalent representation. We implement and evaluate five designs. In each, the user is positioned at the center of the chart and perceives the information through positional sound sources.

We introduce a novel visual bracketing method that provides detail-in-context views where the inner part contains the Focus bracketed by the context information at a lower semantic level. We demonstrate two designs for Web search result visualization that obviate the need to frequently select the next button for viewing multiple search results.

Models for visualization are important, helping the developer and user to understand the visualization process; to follow the connections and the data paths through the system; and to reference and compare the functionality and the limitations of different systems or techniques. Display models specifically classify the data by what type of output can be created. Bertin, J. (1962) described a symbolic reference model that he used to describe images and displays. We review his and other 'display orientated models' describing important aspects of these methods and ideas. We then translate Bertin's scheme into an algebraic form as a method to describe visualizations.

Visualization enables 'seeing the unseen', and provides new insight into the underlying data. However, users far too easily believe or rely on a single representation of the data; this view may be a favourite method, the simplest to perform, or a method that has always been used. A single representation may generate a misinterpretation of the information or provide a situation where the user is missing the 'richness' of the data content. By displaying the data in multiple ways a user may understand the information through different perspectives, overcome possible misinterpretations and perform interactive investigative visualization through correlating the information between views. Thus, the use of multiple views of the same information should be encouraged. We believe the visualization system itself should actively encourage the generation of multiple views by providing appropriate tools to aid in this operation. We present and categorise issues for encouraging multiple views and provide a framework for the generation, management and manipulation of such views.