Arzu Coltekin

Arzu Coltekin
University of Applied Sciences and Arts Northwestern Switzerland | FHNW · Institute of Interactive Technologies

About

145
Publications
42,827
Reads
How we measure 'reads'
A 'read' is counted each time someone views a publication summary (such as the title, abstract, and list of authors), clicks on a figure, or views or downloads the full-text. Learn more
3,013
Citations

Publications

Publications (145)
Article
Full-text available
Various forms of extended reality might empower remote collaboration in ways that the current de facto standards cannot facilitate. Especially when combined by a digital twin of the remote physical object, mixed reality (MR) opens up interesting new ways to support spatial communication. In this study, we explore the use of a digital twin to facili...
Article
Full-text available
There is evidence in literature that collaborative work while using digital tools could benefit from visualizing the real time eye movements of a selected participant, or possibly, several participants. In this study, we examine alternative gaze interaction and visualization design prototypes in a digital collaboration scenario, in which assumed co...
Article
Advancements in extended reality (XR) have inspired new uses and users of advanced visualization interfaces, transforming geospatial data visualization and consumption by enabling interactive 3D geospatial data experiences in 3D. Conventional metrics (e.g., mental rotations test (MRT)) are often used to assess and predict the appropriateness of the...
Conference Paper
Full-text available
Visual saliency is a common computational method to detect attention-drawing regions in images, abiding by top-down and bottom-up processes of visual attention. Computer vision algorithms generate saliency maps, which often undergo a validation step in eye-tracking sessions with human participants in controlled labs. However, due to the covid-19 pa...
Chapter
In this paper, with the overarching goal to make new technologies more useful and usable to older adults, we examine the benefits and shortcoming of conversational user interfaces (CUIs) for older adults, including those with mild cognitive impairment, and dementia-family diseases. We focus on virtual assistants and companions, and approach the que...
Article
Full-text available
Human visual Attention modelling is a persistent interdisciplinary research challenge, gaining new interestin recent years mainly due to the latest developments in deep learning. That is particularly evident insaliency benchmarks. Novel deep learning-based visual saliency models show promising results in capturinghigh-level (top-down) human visual...
Chapter
We explore gestures as interaction methods in virtual reality (VR). We detect hand and body gestures using human pose estimation based on off-the-shelf optical camera images using machine learning, and obtain reliable gesture recognition without additional sensors. We then employ an avatar to prompt users to learn and use gestures to communicate. F...
Article
Full-text available
In this paper we discuss the potential of interactive video as an interface to geospatial information, and demonstrate our findings in a case study driven by goals of promoting a region for tourism and for preventing brain drain. Use of video is controversial due to various technical and human-centric debates; on the one hand, they offer unique qua...
Chapter
Full-text available
Visualizations (i.e., thinking in images internally in the human mind) or externally expressing a concept via graphical means—such as documenting an observation in a hand-drawn or digital visuospatial sketch, or creating a visual output from data—have always been an integral part of scientific inquiry and communication. One might argue that the ‘gr...
Article
Full-text available
After demonstrating that rainbow colors are still commonly used in scientific publications, we comparatively evaluate the rainbow and sequential color schemes on choropleth and isarithmic maps in an empirical user study with 544 participants to examine if a) people intuitively associate order for the colors in these schemes, b) they can successfull...
Article
Full-text available
Immersive analytics, at the intersection of visual analytics and virtual reality has recently gained some traction. Taking a similar approach, VaRt-DataExplorer project is concerned with exploration of data spaces in Virtual Reality (VR) in the context of cultural heritage collections. Our main objective is to facilitate better a understanding and...
Article
Full-text available
Through the ISPRS scientific initiative presented in this paper, we aim to make geospatial educational resources available and discoverable to those who teach and those who want to learn. In earlier work, we designed and implemented a prototype catalogue for geospatial educational resources, aimed at a target audience in higher education. The succe...
Article
Full-text available
With increasing technical feasibility of extended reality (XR) on smartphones and tablets, we also witness increasing versatility in the use of the mixed reality (MR) (i.e., rather than augmented or virtual) in utility-oriented apps (e.g., for navigation, indoor/outdoor spatial planning, entertainment and location based gaming. In cases where user...
Article
Full-text available
This manuscript identifies and documents unsolved problems and research challenges in the extended reality (XR) domain (i.e., virtual (VR), augmented (AR), and mixed reality (MR)). The manuscript is structured to include technology, design, and human factor perspectives. The text is visualization/display-focused, that is, other modalities such as a...
Article
Full-text available
This study compares participants’ performance in extracting information from three-dimensional pie charts with individually extruded sectors in a single map frame against two-dimensional pie and bar charts in adjacent map frames. Specifically, we examine the response accuracy and response times of 181 adults who were asked to (1) identify the highe...
Article
We report on a study in which we examine if the visual design of virtual environments (VEs) affects visuospatial knowledge acquisition in younger and older adults with varying cognitive abilities in the context of navigational learning, specifically when a perspective switch is involved. Perspective switch between first-person and aerial-views is a...
Chapter
Full-text available
In this chapter, we review and summarize the current state of the art in geovisualization and extended reality (i.e., virtual, augmented and mixed reality), covering a wide range of approaches to these subjects in domains that are related to geographic information science. We introduce the relationship between geovisualization, extended reality and...
Article
Identifying land forms and land cover classes are important tasks in image interpretation. Sometimes, a phenomenon called terrain reversal effect (TRE) causes an inverted perception of 3D forms. When this inversion occurs, valleys appear as ridges and vice versa. While the TRE can severely impair the ability to identify 3D land forms, ‘correcting’...
Article
Full-text available
Terrain reversal (also known as relief inversion) effect is a common and well-known illusion encountered in shaded relief maps and satellite imagery where the main depth cue is shading/shadows (Imhof, 1967; Bernabe-Poveda, Callejo, & Ballari, 2005; Saraf, Das, Agarwal, & Sundaram, 1996; Biland & Çöltekin, 2016; Çöltekin, Rautenbach, Coetzee, & Mokw...
Conference Paper
Gaze-Contingent Displays (GCDs) can improve visual search performance on large displays. GCDs, a Level Of Detail (LOD) management technique, discards redundant peripheral detail using various human visual perception models. Models of depth and contrast perception (e.g., depth-of-field and foveation) have often been studied to address the trade-off...
Article
Full-text available
Existing geospatial educational resources are not always easy to find and to integrate into an academic module, amongst others, because the required metadata is not available. As a consequence, simple search attempts do not bring us to these resources, and we miss out on some material that may be very useful in teaching and learning. Our aim is to...
Conference Paper
Gaze-Contingent Displays (GCDs) can improve visual search performance on large displays. GCDs, a Level Of Detail (LOD) management technique, discards redundant peripheral detail using various human visual perception models. Models of depth and contrast perception (e.g., depth-of-field and foveation) have often been studied to address the trade-off...
Article
Full-text available
Relief inversion effect is a perceptual phenomenon that leads to an inverted perception of convex and concave shapes. This perceptual inversion occurs in scenes where the shading/shadows act as the main depth cue. In visuospatial displays, such as shaded relief maps, the positioning of the shadows in the northern slopes, thus when light source plac...
Article
Full-text available
Navigating in unfamiliar environments is a complex task that requires considerable cognitive resources to memorize (and eventually learn) a route. In general, virtual environments (VEs) can be useful tools in training for route learning and improving route recall. However, the visual information presented in VEs, that is, what we choose to present...
Article
Full-text available
Cognitive training approaches using virtual environments (VEs) might counter age-related visuospatial memory decline and associated difficulties in wayfinding. However, the effects of the visual design of a VE in route learning are not fully understood. Therefore, we created a custom-designed VE optimized for route learning, with adjusted levels of...
Article
Full-text available
Geovisualization is primarily understood as the process of interactively visualizing geographic information in any of the steps in spatial analyses, even though it can also refer to the visual output (e.g., plots, maps, combinations of these), or the associated techniques. Rooted in cartography, geovisualization emerged as a research thrust with th...
Article
Terrain reversal effect (TRE) causes reversed 3D shape perception in satellite images and shaded relief maps (SRMs), and introduces difficulties in identifying landforms such as valleys and ridges. With this paper, in a controlled laboratory experiment, we compare how well 27 participants could identify valleys and ridges over 33 locations using SR...
Conference Paper
In its broader scope, this paper is concerned about understanding how (visualization) designs of virtual environments (VE) interact with navigational memory. We optimized the design of a VE for route learning following specific visualization guidelines that we derived from previous literature, and tested it with a typical navigational recall task w...
Article
Modeling and simulation are recognized as effective tools for management and decision support across various disciplines; however, poor communication of results to the end users is a major obstacle for properly using and understanding model output. Visualizations can play an essential role in making modeling results accessible for management and de...
Article
Full-text available
Eye movements provide insights into what people pay attention to, and therefore are commonly included in a variety of human-computer interaction studies. Eye movement recording devices (eye trackers) produce gaze trajectories, that is, sequences of gaze location on the screen. Despite recent technological developments that enabled more affordable h...
Data
Simulated trajectories used in method comparison and sensitivity analysis. (ZIP)
Data
Anonymised gaze and mouse trajectories for ten participants in twelve tracing tasks. (ZIP)
Data
R implementation of the new dynamic interaction measure. (ZIP)
Article
Broadly, this paper is about designing memorable 3D geovisualizations for spatial knowledge acquisition during (virtual) navigation. Navigation is a fundamentally important task, and even though most people navigate every day, many find it difficult in unfamiliar environments. When people get lost in an unfamiliar environment, or are unable to reme...
Conference Paper
This paper presents preliminary results on a visual complexity study with maps where we attempt quantifying generalization quality using algorithmic visual complexity measures.
Conference Paper
The possibility of digital interactivity requires us to reenvision the map reader as the map user, and to address the new perceptual, cognitive, cultural, and practical considerations that now influence the user's experience with interactive maps and visualizations. Here, we present an agenda for empirical research on these users and the interactiv...
Article
We report on how visual realism might influence map-based route learning performance in a controlled laboratory experiment with 104 male participants in a competitive context. Using animations of a dot moving through routes of interest, we find that participants recall the routes more accurately with abstract road maps than with more realistic sate...
Article
We present a study on human perception of map complexity, with the objective of better understanding design decisions that may lead to undesirable levels of complexity in web maps. We compare three complexity metrics to human ratings of complexity obtained through a user survey. Specifically, we use two algorithmic approaches published by others, w...
Article
Full-text available
The possibility of digital interactivity requires us to reenvision the map reader as the map user, and to address the perceptual, cognitive, cultural, and practical considerations that influence the user’s experience with interactive maps and visualizations. In this article, we present an agenda for empirical research on this user and the interacti...
Article
Over four workshops, we collected community input on what people considered as persistent challenges in geovisualization with the participation of 72 experts from various sub-domains of geographic information science and technology. We categorize and analyze this bottom-up input, and contrast it with the previously published research challenges bas...
Article
Full-text available
We demonstrate the use of the ambient/focal coeffcient K for studying the dynamics of visual behavior when performing cartographic tasks. Participants viewed a cartographic map and satellite image of Barcelona while performing a number of map-related tasks. Cartographic maps can be viewed as summary representations of reality, while satellite image...
Article
In this paper, we first present a procedure derived from related vision and perception literature to calculate the colour metric ΔE00, as our previous empirical research let us believe that this is a reliable metric that can be useful in cartographic design decisions (Brychtová and Çöltekin, 2015; 2016). In earlier work, we demonstrated that increa...
Article
In this paper, we first present a procedure derived from related vision and perception literature to calculate the colour metric ΔE00, as our previous empirical research let us believe that this is a reliable metric that can be useful in cartographic design decisions (Brychtová and Çöltekin, 2015; 2016). In earlier work, we demonstrated that increa...
Article
We demonstrate the use of the ambient/focal coecient K for studying the dynamics of visual behavior when performing cartographic tasks. Participants viewed a cartographic map and satellite image of Barcelona while performing a number of map-related tasks. Cartographic maps can be viewed as summary representations of reality, while satellite images...
Article
Full-text available
We compared the ability of two legend designs on a soil-landscape map to efficiently and effectively support map reading tasks with the goal of better understanding how the design choices affect user performance. Developing such knowledge is essential to design effective interfaces for digital earth systems. One of the two legends contained an alph...
Conference Paper
The use of virtual environments (VE) for navigation-related studies, such as spatial cognition and path retrieval has been widely adopted in cognitive psychology and related fields. What motivates the use of VEs for such studies is that, as opposed to real-world, we can control for the confounding variables in simulated VEs. When simulating a geogr...
Conference Paper
In this study, we first develop a hypothesis that existing quantitative visual complexity measures will overall reflect the level of cartographic generalization, and test this hypothesis. Specifically, to test our hypothesis, we first selected common geovisualization types (i.e., cartographic maps, hybrid maps, satellite images and shaded relief ma...
Conference Paper
Whether and when should we show data in 3D is an on-going debate in communities conducting visualization research. A strong opposition exists in the information visualization (Infovis) community, and seemingly unnecessary/unwarranted use of 3D, e.g., in plots, bar or pie charts, is heavily criticized. The scientific visualization (Scivis) community...
Research
Full-text available
In this study, we first develop a hypothesis that existing quantitative visual complexity measures will overall reflect the level of cartographic generalization, and test this hypothesis. Specifically, to test our hypothesis, we first selected common geovisualization types (i.e., cartographic maps, hybrid maps, satellite images and shaded relief ma...
Article
Topographic maps are among the most commonly used map types, however, their complex and information-rich designs depicting natural, human-made and cultural features make them difficult to read. Regardless of their complexity, spatial planners make extensive use of topographic maps in their work. On the other hand, various studies suggest that map l...
Article
Elevation change is critical for choosing a route when bicycling. We detail an empirical study in which we comparatively evaluated three linear symbolization types (color hue, color-coded arrows, and elevation profiles) to depict elevation change in bicycle maps for two common bicycle route planning tasks: relative height detection and slope identi...
Article
Full-text available
In this study, we first develop a hypothesis that existing quantitative visual complexity measures will overall reflect the level of cartographic generalization, and test this hypothesis. Specifically, to test our hypothesis, we first selected common geovisualization types (i.e., cartographic maps, hybrid maps, satellite images and shaded relief ma...
Article
Full-text available
Whether and when should we show data in 3D is an on-going debate in communities conducting visualization research. A strong opposition exists in the information visualization (Infovis) community, and seemingly unnecessary/unwarranted use of 3D, e.g., in plots, bar or pie charts, is heavily criticized. The scientific visualization (Scivis) community...
Article
Full-text available
Informal settlements are a common occurrence in South Africa, and to improve in-situ circumstances of communities living in informal settlements, upgrades and urban design processes are necessary. Spatial data and maps are essential throughout these processes to understand the current environment, plan new developments, and communicate the planned...
Article
Full-text available
The use of virtual environments (VE) for navigation-related studies, such as spatial cognition and path retrieval has been widely adopted in cognitive psychology and related fields. What motivates the use of VEs for such studies is that, as opposed to real-world, we can control for the confounding variables in simulated VEs. When simulating a geogr...
Article
Full-text available
Relief inversion (or terrain reversal) effect is a well-known phenomenon in cartography that occurs when shadow is the main depth cue for three-dimensional shape perception. Light direction has been suggested as the main cause of this effect. However, the prevalence of relief inversion effect with regard to the changing light direction is currently...
Article
Full-text available
Whether and when should we show data in 3D is an on-going debate in communities conducting visualization research. A strong opposition exists in the information visualization (Infovis) community, and seemingly unnecessary/unwarranted use of 3D, e.g., in plots, bar or pie charts, is heavily criticized. The scientific visualization (Scivis) community...
Article
Full-text available
Informal settlements are a common occurrence in South Africa, and to improve in-situ circumstances of communities living in informal settlements, upgrades and urban design processes are necessary. Spatial data and maps are essential throughout these processes to understand the current environment, plan new developments, and communicate the planned...
Article
Full-text available
The use of virtual environments (VE) for navigation-related studies, such as spatial cognition and path retrieval has been widely adopted in cognitive psychology and related fields. What motivates the use of VEs for such studies is that, as opposed to real-world, we can control for the confounding variables in simulated VEs. When simulating a geogr...
Article
Geographic Information Systems (GIS) are complex software environments and we often work with multiple tasks and multiple displays when we work with GIS. However, user input is still limited to mouse and keyboard in most workplace settings. In this project, we demonstrate how the use of gaze and feet as additional input modalities can overcome time...
Article
Full-text available
Geographic Information Systems (GIS) are complex software environments and we often work with multiple tasks and multiple displays when we work with GIS. However, user input is still limited to mouse and keyboard in most workplace settings. In this project, we demonstrate how the use of gaze and feet as additional input modalities can overcome time...
Article
The spatial distance (gap) between map symbols can have a great impact on their discriminability, however, there is little empirical evidence to establish spatial and attribute thresholds. In this paper, we examine the effect of the spatial gap in discriminability of color hue and value, that is, we conducted an online study to obtain performance m...
Article
The Social Atlas of Europe, as the title suggests, takes on a job of mapping social issues in Europe using mainly cartograms. The book includes the European Union (EU) member and candidate countries as well as the European Economic Area (EEA) and the Schengen countries. The thematic coverage is as impressive as the geographic coverage: identity and...
Article
Full-text available
In the last decades, 3D city models appear to have been predominantly used for visualisation; however, today they are being increasingly employed in a number of domains and for a large range of tasks beyond visualisation. In this paper, we seek to understand and document the state of the art regarding the utilisation of 3D city models across multip...
Article
Full-text available
Big data has now become a strong focus of global interest that is increasingly attracting the attention of academia, industry, government and other organizations. Big data can be situated in the disciplinary area of traditional geospatial data handling theory and methods. The increasing volume and varying format of collected geospatial big data pre...
Chapter
Atlases are one of the most complex geovisualization environments as they are very information-rich. Within these environments, a well-designed user interface is essential to explore the variety of atlas maps and media. Involving technology-affine digital natives in the interface design process seems self-evident to provide appealing and intuitivel...
Conference Paper
Full-text available
Visual variables were originally proposed for hard copy maps printed in black and white by Bertin in 1980s. However, we can now generate various digital geovisualization products that are inherently different from printed maps, such as interactive 3D city models. Additional visual variables have been proposed for some of these new geovisualizations...
Article
Full-text available
In this paper we report results from a qualitative user experiment (n=107) designed to contribute to understanding the impact of various levels of complexity (mainly based on levels of detail, i.e., LoD) in 3D city models, specifically on the participants’ orientation and cognitive (mental) maps. The experiment consisted of a number of tasks motiva...
Article
Full-text available
In the context of climate change, both climate researchers and decision makers deal with uncertainties, but these uncertainties differ in fundamental ways. They stem from different sources, cover different temporal and spatial scales, might or might not be reducible or quantifiable, and are generally difficult to characterize and communicate. Hence...
Article
We present an analysis of the influence of colour distance on the user experience with choropleth and chorochromatic maps. We systematically evaluated five sequential and five qualitative colour schemes in a two-stage user experiment. At first, we conducted an online study to obtain performance metrics accuracy and response time from a large, heter...