This paper investigates associations, explicit representations of relations between multiple views in Mixed Reality (MR). While research on 2D desktop environments offers extensive recommendations for communicating relations between multiple views, MR environments lack such systematic guidance, necessitating adapted solutions that consider their spatial affordances. To address this gap, we systematically explored association techniques in existing research. Building on established 2D multi-view literature and refining insights from prior design principles, we developed a codebook to describe view relations and their representations. Applying it to a corpus of 44 immersive multi-view approaches, we identified recurring design strategies and synthesized them into a design space of visual association techniques adapted for immersive contexts. Based on a lightweight prototyping framework, we validate the utility of the design space through three envisioning scenarios, demonstrating how associations can support exploration, coordination, and sensemaking in MR applications. Our results inform the design of MR multi-view environments.

Abstract Multivariate line data is critical for analyzing flow fields, agent systems, and dynamic trajectories. Embedding secondary variables along spatial paths using surface‐based primitives such as ribbons and circular tubes introduces challenges related to perspective, scale, and distortion. Perceptual trade‐offs due to these challenges remain unclear. We address this gap through a controlled user study with 10 experts in computational fluid dynamics and visualization, performing four identical analysis tasks involving both spatial (requiring location‐based relationships) and non‐spatial (requiring attribute value comparisons) aspects. The tasks were performed using a prototype with interactivity limited to controlling the camera. While quantitative measures showed no significant performance differences between embedded visualizations on ribbons and tubes, we found a clear subjective preference for tubes among the study participants. Furthermore, their feedback indicates surface‐based embeddings are generally helpful and should be utilized more often.

We explore the metaphorical "daily memory pill"concept - a brief pictorial lifelog recap aimed at reviving and preserving memories. Leveraging psychological strategies, we explore the potential of such summaries to boost autobiographical memory. We developed an automated lifelogging memory prosthesis and a research protocol (Automated Memory Validation "AMV") for conducting privacy-aware, in-situ evaluations. We conducted a real-world lifelogging experiment for a month (n=11). We also designed a browser "Pixel Memories"for browsing one-week worth of lifelogs. The results suggest that daily timelapse summaries, while not yielding significant memory augmentation effects, also do not lead to memory degradation. Participants' confidence in recalled content remains unaltered, but the study highlights the challenge of users' overestimation of memory accuracy. Our core contributions, the AMV protocol and "Pixel Memories"browser, advance our understanding of memory augmentations and offer a privacy-preserving method for evaluating future ubicomp systems.

In recent years, data-driven stories have found a firm footing in journalism, business, and education. They leverage visualization and storytelling to convey information to broader audiences. Likewise, immersive technologies, like augmented and virtual reality devices, provide excellent potential for exploring and explaining data, thus inviting research on how data-driven storytelling transfers to immersive environments. To gain a better understanding of this exciting novel research area, we conducted a scoping review on the emerging notion of immersive data-driven storytelling, extended by surveying immersive data journalism and by analyzing immersive games, selected based on community reviews and tags. We present our methodology for the survey and discuss prominent themes that coalesce the knowledge we extracted from the literature, journalism, and games. These themes include, among others, the spatial embodiment of narration, the incorporation of the users and their context into narratives, and the balance between guiding the user versus promoting serendipity. Our discussion of these themes reveals research opportunities and challenges that will inform the design of immersive data-driven stories in the future.

This paper presents Pearl, a mixed-reality approach for the analysis of human movement data in situ. As the physical environment shapes human motion and behavior, the analysis of such motion can benefit from the direct inclusion of the environment in the analytical process. We present methods for exploring movement data in relation to surrounding regions of interest, such as objects, furniture, and architectural elements. We introduce concepts for selecting and filtering data through direct interaction with the environment, and a suite of visualizations for revealing aggregated and emergent spatial and temporal relations. More sophisticated analysis is supported through complex queries comprising multiple regions of interest. To illustrate the potential of Pearl, we developed an Augmented Reality-based prototype and conducted expert review sessions and scenario walkthroughs in a simulated exhibition. Our contribution lays the foundation for leveraging the physical environment in the in-situ analysis of movement data.

Augmented Reality (AR) interfaces support users by providing access to digital content within real-world environments. However, displaying content at the users’ eye level might result in the occlusion of the real world. Therefore, it requires finding AR content placement areas that free the users’ field of vision. In this work, we systematically investigate two content placement areas beyond the users’ eye level: the ceiling and floor. To understand how potential users perceive virtual content on the ceiling and floor and how the content should be placed on these areas, we conducted two user studies. While the first exploratory study showed the general usefulness of either area, the second quantitative study allowed us to define optimal placement parameters regarding visibility and comfort. With insights from our studies, we provide design recommendations for future AR applications that support 2D content presentation on the ceiling and the floor.

Reading is a fundamental activity to obtain information both in the real and the digital world. Virtual reality (VR) allows novel approaches for users to view, read, and interact with a text. However, for efficient reading, it is necessary to understand how a text should be displayed in VR without impairing the VR experience. Therefore, we conducted a study with 18 participants to investigate text presentation type and location in VR. We compared world-fixed, edge-fixed, and head-fixed text locations. Texts were displayed using Rapid Serial Visual Presentation (RSVP) or as a paragraph. We found that RSVP is a promising presentation type for reading short texts displayed in edge-fixed or head-fixed location in VR. The paragraph presentation type using world-fixed or edge-fixed location is promising for reading long text if movement in the virtual environment is not required. Insights from our study inform the design of reading interfaces for VR applications.

Museums are essential to make culture accessible to the mass audience. Human museum guides are important to explain the presented artifacts to the visitors. Recently, museums started to experiment with enhancing exhibitions through mixed reality. It enables cultural exhibitors to provide each visitor with an individualized virtual guide that adapts to the visitor's interests. The effect of the presence and appearance of a virtual museum guide is, however, unclear. In this paper, we compare a real-world guide with a realistic, an abstract, and an audio-only representation of the virtual guide. Participants followed four multimodal presentations while we investigated the effect on comprehension and perceived co-presence. We found that a realistic representation of a virtual guide increases the perceived co-presence and does not adversely affect the comprehension of learning content in mixed reality exhibitions. Insights from our study inform the design of virtual guides for real-world exhibitions.

In the era of ubiquitous computing, people expect applications to work across different devices. To provide a seamless user experience it is therefore crucial that interfaces and interactions are consistent across different device types. In this paper, we present a method to create gesture sets that are consistent and easily transferable. Our proposed method entails 1) the gesture elicitation on each device type, 2) the consolidation of a unified gesture set, and 3) a final validation by calculating a transferability score. We tested our approach by eliciting a set of user-defined gestures for reading with Rapid Serial Visual Presentation (RSVP) of text for three device types: phone, watch, and glasses. We present the resulting, unified gesture set for RSVP reading and show the feasibility of our method to elicit gesture sets that are consistent across device types with different form factors.

Smart glasses are increasingly being used in professional contexts. Having key applications such as short messaging and newsreader, they enable continuous access to textual information. In particular, smart glasses allow reading while performing other activities as they do not occlude the user's world view. For efficient reading, it is necessary to understand how a text should be presented on them. We, therefore, conducted a study with 24 participants using a Microsoft HoloLens to investigate how to display text on smart glasses while walking and sitting. We compared text presentation in the top-right, center, and bottom-center positions with Rapid Serial Visual Presentation (RSVP) and line-by-line scrolling. We found that text displayed in the top-right of smart glasses increases subjective workload and reduces comprehension. RSVP yields higher comprehension while sitting. Conversely, reading with scrolling yields higher comprehension while walking. Insights from our study inform the design of reading interfaces for smart glasses.

Reflecting on previous activities can improve episodic memory and well-being. While manually recording activities and experiences is not always feasible, there is a range of mobile sensors that allow implicit recording of users' lives. In this work, we investigate how reflection on daily summaries created from implicitly collected data improves episodic memory. Therefore, we built ReflectiveDiary, an Android application that collects personal data streams to create daily summaries automatically. Over the course of 16 days, we collected data from 11 participants using information, such as calls, messages, and calendar data to help people recollect their activities. By comparing reflected with non-reflected days, we show that reflecting on implicitly collected data improves remembering of events and their surrounding details. We further present an analysis of different types of memory cues and their usefulness to inform the design of reflective tools that help people to improve their episodic memory.

In this paper, we investigate the concept of gaze-based interaction with 3D user interfaces. We currently see stereo vision displays becoming ubiquitous, particularly as auto-stereoscopy enables the perception of 3D content without the use of glasses. As a result, application areas for 3D beyond entertainment in cinema or at home emerge, including work settings, mobile phones, public displays, and cars. At the same time, eye tracking is hitting the consumer market with low-cost devices. We envision eye trackers in the future to be integrated with consumer devices (laptops, mobile phones, displays), hence allowing the user's gaze to be analyzed and used as input for interactive applications. A particular challenge when applying this concept to 3D displays is that current eye trackers provide the gaze point in 2D only (x and y coordinates). In this paper, we compare the performance of two methods that use the eye's physiology for calculating the gaze point in 3D space, hence enabling gaze-based interaction with stereoscopic content. Furthermore, we provide a comparison of gaze interaction in 2D and 3D with regard to user experience and performance. Our results show that with current technology, eye tracking on stereoscopic displays is possible with similar performance as on standard 2D screens.