arXiv subjects

Miguel A. Nacenta

Publications and source records attributed to Miguel A. Nacenta.

8 recordsLinked to original sources

arXiv2026

Q&A or Document-Based? The Effects of Interface Type on How Screen Reader Users Access Interconnected Documents

Blind and low-vision (BLV) users are increasingly engaging with large language model (LLM) interfaces to access documents, but it is unclear how such systems support or hinder their ability to build interconnected knowledge. To examine this gap, we compared a Question-Answer Interface (QAI) that supports open-ended conversational inquiry, with a Document Interface (DI) based mostly on traditional structured text document navigation. We recruited 16 BLV screen reader users where they used both interfaces to explore two fictional worlds. Data from interaction logs, concept maps, decision-based tasks, and semi-structured interviews provide comparative insights into how interface design supports knowledge construction. Findings show that participants visited more distinct documents with the DI and formed larger and more correct mental models with the DI than with the QAI. They were also more able to apply knowledge they had gained. Simultaneously, many still preferred the QAI and often estimated that they had explored more, formed better mental models and applied their models better when acquiring the information with the QAI, despite this not being the case. Our analysis suggests possible interface design reasons for these differences and highlights some of the risks introduced by using question-answer interfaces to access information spaces.

cs.HC↗

arXiv2026

"If We Had the Information That We Need to Interpret the World Around Us, We Wouldn't Be Disabled:" Barriers and Opportunities in Information Work among Blind and Sighted Colleagues

Despite recognition of the value of diversity, the way work takes place can fail to support blind or low-vision employees, especially in collaborative work settings. This paper examines how professional teams with diverse visual abilities use information representations (e.g., PDF documents, spreadsheets and charts). A diary study with follow-up individual interviews (23 participants with mixed abilities from 5 teams) and 2 separate focus groups (7 participants from 2 other teams) allowed us to characterize key dimensions of the role of representations in the workplace into four types of interrelated failures and workarounds, influenced by workplace stigmas and shaped by evolving social dynamics towards interdependent information work. We contribute this new empirically supported conceptual understanding of representation use in workplaces that can help design and improve the experiences of mixed-ability teams doing knowledge work in the current technological landscape.

cs.HC↗

arXiv2026

Accessibility-Driven Information Transformations in Mixed-Visual Ability Work Teams

Blind and low-vision (BLV) employees in mixed-visual ability teams often encounter information (e.g., PDFs, diagrams) in inaccessible formats. To enable teamwork, teams must transform these representations by modifying or re-creating them into accessible forms. However, these transformations are frequently overlooked, lack infrastructural support, and cause additional labour. To design systems that move beyond one-off accommodations to effective mixed-ability collaboration, we need a deeper understanding of the representations, their transformations and how they occur. We conducted a week-long diary study with follow-up interviews with 23 BLV and sighted professionals from five legal, non-profit, and consulting teams, documenting 36 transformation cases. Our analysis characterizes how teams perform representational transformations for accessibility: how they are triggered proactively or reactively, how they simplify or enhance, and four common patterns in which workers coordinate with each other to address representational incompatibility. Our findings uncover opportunities for designing systems that can better support mixed-visual ability work.

cs.HC↗

arXiv2026

Locatability and Locatability Robustness of Visual Variables in Single Target Localization

Finding a particular object in a display is important for viewers in many visualizations, for example, when reacting to brushing or to a highlighted object. This can be enabled by making the target object different in one of the visual variables that determine the object's appearance; for example, by changing its color or size. Certain interpretations of the visual search literature have promoted the view that using visual variables such as hue-often labeled as preattentive-would make the target object automatically "popout," implying that an object can be located almost instantly, regardless of the number of objects in the display. In this paper we present a study that serves as a bridge between the extensive visual search literature and visualization, establishing empirical base measurements for the localization task. By testing displays with up to hundreds of objects, we are able to show that none of the common visual variables is immune to the increase in the number of objects. We also provide the first empirically informed comparisons between visual variables for this task in the context of visualization, and show how different visual variables have varying robustness with respect to two additional dimensions: the location of the target and the overall visual arrangement (layout). A free copy of this paper and all supplemental materials are available on our online repository: https://osf.io/z68ak/overview.

cs.HC↗

arXiv2024

TADA: Making Node-link Diagrams Accessible to Blind and Low-Vision People

Diagrams often appear as node-link representations in many contexts, such as taxonomies, mind maps and networks in textbooks. Despite their pervasiveness, they present significant accessibility challenges for blind and low-vision people. To address this challenge, we introduce Touch-and-Audio-based Diagram Access (TADA), a tablet-based interactive system that makes diagram exploration accessible through musical tones and speech. We designed and developed TADA informed by insights gained from an interview study with 15 participants who shared their challenges and strategies for accessing diagrams. TADA enables people to access a diagram by: i) engaging in open-ended touch-based explorations, ii) allowing searching of specific nodes, iii) navigating from one node to another and iv) filtering information. We evaluated TADA with 25 participants and found that it can be a useful tool for gaining different perspectives about the diagram and participants could complete several diagram-related tasks.

cs.HC↗

arXiv2024

Tools and Tasks in Sensemaking: A Visual Accessibility Perspective

Our previous interview study explores the needs and uses of diagrammatic information by the Blind and Low Vision (BLV) community, resulting in a framework called the Ladder of Diagram Access. The framework outlines five levels of information access when interacting with a diagram. In this paper, we connect this framework to include the global activity of sensemaking and discuss its (in)accessibility to the BLV demographic. We also discuss the integration of this framework into the sensemaking process and explore the current sensemaking practices and strategies employed by the BLV community, the challenges they face at different levels of the ladder, and potential solutions to enhance inclusivity towards a data-driven workforce.

cs.HC↗

arXiv2020

The Effectiveness of Interactive Visualization Techniques for Time Navigation of Dynamic Graphs on Large Displays

Dynamic networks can be challenging to analyze visually, especially if they span a large time range during which new nodes and edges can appear and disappear. Although it is straightforward to provide interfaces for visualization that represent multiple states of the network (i.e., multiple timeslices) either simultaneously (e.g., through small multiples) or interactively (e.g., through interactive animation), these interfaces might not support tasks in which disjoint timeslices need to be compared. Since these tasks are key for understanding the dynamic aspects of the network, understanding which interactive visualizations best support these tasks is important. We present the results of a series of laboratory experiments comparing two traditional approaches (small multiples and interactive animation), with a more recent approach based on interactive timeslicing. The tasks were performed on a large display through a touch interface. Participants completed 24 trials of three tasks with all techniques. The results show that interactive timeslicing brings benefit when comparing distant points in time, but less benefits when analyzing contiguous intervals of time.

cs.HC↗

arXiv2014

Case Studies and Challenges in Reproducibility in the Computational Sciences

This paper investigates the reproducibility of computational science research and identifies key challenges facing the community today. It is the result of the First Summer School on Experimental Methodology in Computational Science Research (https://blogs.cs.st-andrews.ac.uk/emcsr2014/). First, we consider how to reproduce experiments that involve human subjects, and in particular how to deal with different ethics requirements at different institutions. Second, we look at whether parallel and distributed computational experiments are more or less reproducible than serial ones. Third, we consider reproducible computational experiments from fields outside computer science. Our final case study looks at whether reproducibility for one researcher is the same as for another, by having an author attempt to have others reproduce their own, reproducible, paper. This paper is open, executable and reproducible: the whole process of writing this paper is captured in the source control repository hosting both the source of the paper, supplementary codes and data; we are providing setup for several experiments on which we were working; finally, we try to describe what we have achieved during the week of the school in a way that others may reproduce (and hopefully improve) our experiments.

cs.CE↗