EuroRVVV: EuroVis Workshop on Reproducibility, Verification, and Validation in Visualization
Permanent URI for this community
Browse
Browsing EuroRVVV: EuroVis Workshop on Reproducibility, Verification, and Validation in Visualization by Issue Date
Now showing 1 - 20 of 42
Results Per Page
Sort Options
Item A Survey on Visualization in Industrial Ergonomics(The Eurographics Association, 2013) Heft, W.; Spitzhirn, M.; Rosenthal, P.; P. Rosenthal and R. S. Laramee and M. Kirby and G. L. KindlmannThe field of ergonomics is widely used in industry and other fields close to human work. This paper presents an overview about the state of the art in virtual ergonomics with regard to visualization issues. We consider some of the most popular ergonomics tools and their analysis functions like visibility and accessibility of objects or the ergonomic stress of specific extremities. Advantages and disadvantages are discussed with respect to aspects of intuitive and reliable information display.Item A Study Of Discretization Errors In Volume Rendering Integral Approximations(The Eurographics Association, 2013) Etiene, Tiago; Kirby, Robert M.; Silva, Cláudio T.; P. Rosenthal and R. S. Laramee and M. Kirby and G. L. KindlmannWe present a study of the influence of different approximation schemes on the convergence rate of volume rendering integral (VRI) numerical approximations. We experimentally evaluate the impact of numerical integration techniques on the rate of convergence to the correct solution of the VRI on a single ray.We report that the discretization of both the inner and outer integrals have influence on the overall convergence rate. Then, we present results related to the (traditional) pre-integrated and second-order pre-integrated algorithms. In practice, we observed that pre-integrated lookup tables provide second and third order convergence rates for the VRI approximation, respectively. Our results also suggest that the convergence rate drops one order of magnitude for the second-order algorithm when lookup tables are numerically computed using low sample rates. Also, the convergence of both algorithms drops to linear when the attenuation within ray segment is neglected.Item Gaze into Hierarchy: A Practice-oriented Eye Tracking Study(The Eurographics Association, 2013) Müller, N. H.; Liebold, B.; Pietschmann, D.; Ohler, P.; Rosenthal, P.; P. Rosenthal and R. S. Laramee and M. Kirby and G. L. KindlmannThe visualization of hierarchical data is a wide field and plenty of different approaches have been proposed for various applications and purposes. A comprehensive survey on hierarchy visualizations was recently presented by Schulz et al. [SHS11]. Although every approach has its own claimed advantages, for practitioners it is often unclear what these mean in the specific context and which method to use.Item Using User-Centered Techniques for the Design and Evaluation of Interactive Visualizations to Support Urban and Regional Planning: Case Study Bogota 21(The Eurographics Association, 2013) Prieto, D. Fernandez; Zeckzer, D.; Hernández, J. T.; P. Rosenthal and R. S. Laramee and M. Kirby and G. L. KindlmannUser-centered techniques and evaluations are very important for the design of interactive visualizations. We applied the UCIV4 Planning Approach (User-Centered Interactive Visualizations for Planning) within the project ''Bogotá 21''. This approach proposes three activities that aim at gathering information about users and perform early evaluations as part of the end of each phase of the process. This paper presents the lessons learned from applying this user-centered approach to the ''Bogotá 21'' project and provides recommendations for improving future instantiations of this and approach and the included evaluations.Item Reproducibility Made Easy(The Eurographics Association, 2015) Freire, Juliana; W. Aigner and P. Rosenthal and C. ScheideggerEver since Francis Bacon, a hallmark of the scientific method has been that experiments should be described in enough detail that they can be repeated and perhaps generalized. When Newton said that he could see farther because he stood on the shoulders of giants, he depended on the truth of his predecessors' observations and the correctness of their calculations. In modern terms, this implies the possibility of repeating results on nominally equal configurations and then generalizing the results by replaying them on new data sets, and seeing how they vary with different parameters. In principle, this should be easier for computational experiments than for natural science experiments, because not only can computational processes be automated but also computational systems do not suffer from the ''biological variation'' that plagues the life sciences. Unfortunately, the state of the art falls far short of this goal. Most computational experiments are specified only informally in papers, where experimental results are briefly described in figure captions; the code that produced the results is seldom available; and configuration parameters change results in unforeseen ways.Item On the Reproducibility of our Biomolecular Visualization(The Eurographics Association, 2015) Scharnowski, Katrin; Krone, Michael; Reina, Guido; Ertl, Thomas; W. Aigner and P. Rosenthal and C. ScheideggerWe reflect on the reproducibility of our work presented at EuroVis 2014 [SKR 14], which applies deformable models to compare molecular surfaces. We discuss both negative and positive aspects of our work in terms of reproducibility and put the aspects in a wider, more general context, in particular for the more critical points.Item Should we Dream the Impossible Dream of Reproducibility in Visual Analytics Evaluation?(The Eurographics Association, 2015) Smuc, Michael; Schreder, Günther; Mayr, Eva; Windhager, Florian; W. Aigner and P. Rosenthal and C. ScheideggerEspecially in the field of Visual Analytics, where a lot of design decisions have to be taken, researchers strive for reproducible results. We present two different evaluation approaches aiming for more general design knowledge: the isolation of features and the abstraction of results. Both approaches have potentials, but also problems with respect to generating reproducible results. We discuss whether reproducibility is possible or even the right aim in the evaluation of Visual Analytics methods.Item On the Reproducibility of VisRuption: A Tool for Intuitive and Efficient Visualization of Airline Disruption Data(The Eurographics Association, 2015) Müller, Nicholas Hugo; Pfeiffer, Linda; Ohler, Peter; Rosenthal, Paul; W. Aigner and P. Rosenthal and C. ScheideggerManaging the vast amount of resources and processes of large airlines with several hundred aircraft and several thousand operated flights per day is a very complex task and makes computer-aided operation irreplaceable. Moreover, there is a multitude of disruptions which can occur every day during airline operation and can result in very expensive delays or cancellations [CTA04,MHR10,Now09]. In our paper at EuroVis 2013 [RPMO13], we have presented a design study about the tool VisRuption for providing an intuitive and efficient access to airline disruption data.Item A Mixed Approach for the Evaluation of a Guided Exploratory Visualization System(The Eurographics Association, 2015) Boukhelifa, Nadia; Bezerianos, Anastasia; Lutton, Evelyne; W. Aigner and P. Rosenthal and C. ScheideggerWe summarise and reflect upon our experience in evaluating a guided exploratory visualization system. Our system guides users in their exploration of multidimensional datasets to pertinent views of their data, where the notion of pertinence is defined by automatic indicators, such as the amount of visual patterns in the view, and subjective user feedback obtained during their interaction with the tool. To evaluate this type of system, we argue for deploying a collection of validation methods that are: user-centered, observing the utility and effectiveness of the system for the end-user; and algorithm-centered, analysing the computational behaviour of the system. We report on observations and lessons learnt from working with expert users both for the design and the evaluation of our system.Item Frontmatter: EuroRV3 2015 EuroVis Workshop on Reproducibility, Verification, and Validation in Visualization(Eurographics Association, 2015) Rosenthal, Paul; Aigner, Wolfgang; Scheidegger, Carlos; -Item Choosing the Right Sample? Experiences of Selecting Participants for Visualization Evaluation(The Eurographics Association, 2015) Kriglstein, Simone; Pohl, Margit; W. Aigner and P. Rosenthal and C. ScheideggerConducting and reporting evaluation studies has become more and more popular over the last few years in the information visualization community. A big challenge is to describe such studies in a way such that the investigations are repeatable and comparable with other studies. This not only includes the description of methodology, tasks, and procedure of the study but also information about the participants - including the reasons for their selection - to make the work reproducible and to assess its validity. In this paper we give a short overview about our research that we conducted in the past to show in which context and situations which types of test persons (e.g., students or experts) were considered.Item Reproducibility, Verification, and Validation of Experiments on the Marschner-Lobb Test Signal(The Eurographics Association, 2015) Vad, Viktor; Csébfalvi, Balázs; Rautek, Peter; Gröller, Eduard; W. Aigner and P. Rosenthal and C. ScheideggerThe Marschner-Lobb (ML) test signal has been used for two decades to evaluate the visual quality of different volumetric reconstruction schemes. Previously, the reproduction of these experiments was very simple, as the ML signal was used to evaluate only compact filters applied on the traditional Cartesian lattice. As the Cartesian lattice is separable, it is easy to implement these filters as separable tensor-product extensions of well-known 1D filter kernels. Recently, however, non-separable reconstruction filters have received increased attention that are much more difficult to implement than the traditional tensor-product filters. Even if these are piecewise polynomial filters, the space partitions of the polynomial pieces are geometrically rather complicated. Therefore, the reproduction of the ML experiments is getting more and more difficult. Recently, we reproduced a previously published ML experiment for comparing Cartesian Cubic (CC), Body-Centered Cubic (BCC), and Face-Centered Cubic (FCC) lattices in terms of prealiasing. We recognized that the previously applied settings were biased and gave an undue advantage to the FCC-sampled ML representation. This result clearly shows that reproducibility, verification, and validation of the ML experiments is of crucial importance as the ML signal is the most frequently used benchmark for demonstrating the superiority of a reconstruction scheme or volume representations on non-Cartesian lattices.Item Debugging Vega through Inspection of the Data Flow Graph(The Eurographics Association, 2015) Hoffswell, Jane; Satyanarayan, Arvind; Heer, Jeffrey; W. Aigner and P. Rosenthal and C. ScheideggerVega is a declarative visualization grammar that decouples specification from execution to allow users to focus on the visual representation rather than low-level implementation decisions. However, this representation comes at the cost of effective debugging as its execution is obfuscated. By presenting the developer with Vega's data flow graph along with interactive capabilities, we can bridge the gap between specification and execution to enable direct inspection of the connections between each component. This inspection can augment the developer's mental model of the specification, enabling the developer to more easily identify areas of interest and implement changes to the resulting visualization.Item On the Reproducibility of Line Integral Convolution for Real-Time Illustration of Molecular Surface Shape and Salient Regions(The Eurographics Association, 2015) Lawonn, Kai; Krone, Michael; Ertl, Thomas; Preim, Bernhard; W. Aigner and P. Rosenthal and C. ScheideggerIn this paper, we discuss the reproducibility of our work presented at EuroVis 2014 [LKEP14], which describes an illustrative rendering method tailored to molecular surfaces.We distinguish between the reproducibility of the data sets that were used for figures and performance analysis and the reproducibility in the sense of re-implementing the method. For the latter, we focus on each step of the algorithm and discuss the implementation challenges. We give further details and explain the most difficult parts. Additionally, we discuss how the models that were used can be recreated and the availability of the underlying data. Finally, we discuss the current state of reproducibility of our method and reflect on the problem of offering the source code of a research project in general.Item OphthalVis - Making Data Analytics of Optical Coherence Tomography Reproducible(The Eurographics Association, 2016) Rosenthal, Paul; Ritter, Marc; Kowerko, Danny; Heine, Christian; Kai Lawonn and Mario Hlawitschka and Paul RosenthalIn this paper, we discuss the issues of the current state of the art in optical coherence tomography with respect to reproducibility. We present our findings about the internal computations and data storage methods of the currently used devices. The gained knowledge was used to implement a tool to read a variety of OCT file formats and reproduce the visualizations used in daily clinical routine.Item EuroRV3 2016: Frontmatter(Eurographics Association, 2016) Kai Lawonn; Mario Hlawitschka; Paul Rosenthal;Item Uncertainty and Reproducibility in Medical Visualization(The Eurographics Association, 2016) Linsen, Lars; Al-Taie, Ahmed; Ristovski, Gordan; Preusser, Tobias; Hahn, Horst K.; Kai Lawonn and Mario Hlawitschka and Paul RosenthalThe medical visualization pipeline is affected by various sources of uncertainty. Many errors may occur and several assumptions are made in the various processing steps from the image acquisition to the rendering of the visualization output, which induce uncertainty. High uncertainty leads to low robustness of the algorithms impacting reproducibility of the results. We present how uncertainty can be mathematically described in the medical context. Moreover, in medical applications, the visualization is typically based on a segmentation of the medical images. We propose a method to capture uncertainty in image segmentation and present extensions to ensemble and multi-modal image segmentation.Item An Introduction to Evaluation in Medical Visualization(The Eurographics Association, 2016) Smit, Noeska; Lawonn, Kai; Kai Lawonn and Mario Hlawitschka and Paul RosenthalMedical visualization papers often deal with data that is interpreted by medical domain experts in a research or clinical context. Since visualizations are by definition designed to be interpreted by a human observer, often an evaluation is performed to confirm the utility of a presented method. The exact type of evaluation required is not always clear, especially to new researchers. With this paper, we hope to clarify the different types of evaluation methods that exist and provide practical guidelines to choose the most suitable evaluation method to increase the value of the work.Item Classifying Medical Projection Techniques based on Parameterization Attribute Preservation(The Eurographics Association, 2016) Kreiser, Julian; Ropinski, Timo; Kai Lawonn and Mario Hlawitschka and Paul RosenthalIn many areas of medicine, visualization researchers can help by contributing to to task simplification, abstraction or complexity reduction. As these approaches, can allow a better workflow in medical environments by exploiting easier communication through visualization, it is important to question their reliability and their reproducibility. Therefore, within this short paper, we investigate how projections used in medical visualization, can be classified with respect to the handled data and the underlying tasks. Many of these techniques are inspired by mesh parameterization, which allows for reducing a surface from R3 to R2. This makes complex structures often easier to understand by humans and machines. In the following section, we will classify different algorithms in this area (see Table 1) and discuss how these mappings benefit medical visualization.Item Experiences on Validation of Multi-Component System Simulations for Medical Training Applications(The Eurographics Association, 2016) Law, Yuen C.; Weyers, Benjamin; Kuhlen, Torsten W.; Kai Lawonn and Mario Hlawitschka and Paul RosenthalIn the simulation of multi-component systems, we often encounter a problem with a lack of ground-truth data. This situation makes the validation of our simulation methods and models a difficult task. In this work we present a guideline to design validation methodologies that can be applied to the validation of multi-component simulations that lack of ground-truth data. Additionally we present an example applied to an Ultrasound Image Simulation for medical training and give an overview of the considerations made and the results for each of the validation methods. With these guidelines we expect to obtain more comparable and reproducible validation results from which other similar work can benefit.