Jaemin Jo

dblp:153/7495 · DBLP profile ↗
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31ranked-venue papers
7as first author
19since 2021 · last 2026
0000-0002-5207-6010ORCID · corroborated

Domains — the database's venue-derived domains; a paper can count in several

Graphics, computer vision, multimedia, augmented reality and games · 19 · 5 first-author · 13 since 2021Human-computer interaction and ubiquitous computing · 11 · 2 first-author · 6 since 2021Artificial intelligence and machine learning · 1 · 1 since 2021Computer networks · 1Databases, data management, data science and information retrieval · 1 · 1 since 2021Applied, interdisciplinary, general and emerging computing · 1 · 1 since 2021
YearPublicationVenuePosition
2026 HyPockeTuner: Bringing Hyperparameter Optimization to Mobile Devices
abstract
Hyperparameter optimization (HPO) is a long-running process that can span hours or even days. While recent Human-in-the-Loop HPO systems enable monitoring and steering of the process, they are typically designed for desktop environments, which limits their effectiveness in managing prolonged experiments in practice. To address these limitations, we present HyPockeTuner, an interactive mobile system that enables users to monitor, steer, and reflect on HPO experiments anytime, anywhere from smartphones. Its mobile-tailored interface supports tracking experiment history and visualizing the relationship between user interventions and performance changes. HyPockeTuner also employs a notification workflow that alerts users to important events, reducing the burden of constant monitoring while enabling timely interventions. In a pilot study, we validated that users could readily identify critical events, such as performance improvements and intervention points, through our visualization. Furthermore, two five-day deployment studies with follow-up reflection sessions demonstrated that users could integrate experiment management into their daily routines and reflect on past decisions, generating insights for future improvement.
Donghee Hong, Bongshin Lee, Jinwook Seo, Jaemin Jo
CHI4
2026 Suppression or Deletion: A Restoration-Based Representation-Level Analysis of Machine Unlearning
Yurim Jang, Jaemin Jo, Simon S. Woo
WWW4
2026 Symetra: Visual Analytics for the Parameter Tuning Process of Symbolic Execution Engines
abstract
Abstract Symbolic execution engines such as KLEE automatically generate test cases to maximize branch coverage, but their numerous parameters make it difficult to understand the parameters' impact, leading the user to rely on suboptimal default configurations. While automated tuners have shown promising results, they provide limited insights into why certain configurations work well, motivating the need for Human‐in‐the‐Loop approaches. In this work, we present a visual analytics system, Symetra, designed to support Human‐in‐the‐Loop parameter tuning of symbolic execution engines. To handle a large number of parameters and their configurations, we provide two complementary overviews of their impact on branch coverage values and patterns. Building on these overviews, our system enables collective analysis, allowing the user to contrast groups of configurations and identify differences that may affect branch coverage. We also report on case studies and a Human‐in‐the‐Loop tuning process, demonstrating that experts not only interpreted parameter impacts and identified complementary configurations, but also improved upon fully automated approaches in both branch coverage and tuning efficiency.
Donghee Hong, Minjong Kim, Sooyoung Cha, Jaemin Jo
Comput. Graph. Forum4
2026 GhostUMAP2: Measuring and Analyzing $(r,d)$-Stability of UMAP
abstract
Despite the widespread use of Uniform Manifold Approximation and Projection (UMAP), the impact of its stochastic optimization process on the results remains underexplored. We observed that it often produces unstable results where the projections of data points are determined mostly by chance rather than reflecting neighboring structures. To address this limitation, we introduce $(r,d)$-stability to UMAP: a framework that analyzes the stochastic positioning of data points in the projection space. To assess how stochastic elements-specifically, initial projection positions and negative sampling-impact UMAP results, we introduce "ghosts", or duplicates of data points representing potential positional variations due to stochasticity. We define a data point's projection as $(r,d)$-stable if its ghosts perturbed within a circle of radius $r$ in the initial projection remain confined within a circle of radius $d$ for their final positions. To efficiently compute the ghost projections, we develop an adaptive dropping scheme that reduces a runtime up to 60% compared to an unoptimized baseline while maintaining approximately 90% of unstable points. We also present a visualization tool that supports the interactive exploration of the $(r,d)$-stability of data points. Finally, we demonstrate the effectiveness of our framework by examining the stability of projections of real-world datasets and present usage guidelines for the effective use of our framework.
Myeongwon Jung, Takanori Fujiwara, Jaemin Jo
IEEE Trans. Vis. Comput. Graph.3
2026 Unlearning Comparator: A Visual Analytics System for Comparative Evaluation of Machine Unlearning Methods
abstract
Machine Unlearning (MU) aims to remove target training data from a trained model so that the removed data no longer influences the model's behavior, fulfilling "right to be forgotten" obligations under data privacy laws. Yet, we observe that researchers in this rapidly emerging field face challenges in analyzing and understanding the behavior of different MU methods, especially in terms of three fundamental principles in MU: accuracy, efficiency, and privacy. Consequently, they often rely on aggregate metrics and ad-hoc evaluations, making it difficult to accurately assess the trade-offs between methods. To fill this gap, we introduce a visual analytics system, Unlearning Comparator, designed to facilitate the systematic evaluation of MU methods. Our system supports two important tasks in the evaluation process: model comparison and attack simulation. First, it allows the user to compare the behaviors of two models, such as a model generated by a certain method and a retrained baseline, at class-, instance-, and layer-levels to better understand the changes made after unlearning. Second, our system simulates membership inference attacks (MIAs) to evaluate the privacy of a method, where an attacker attempts to determine whether specific data samples were part of the original training set. We evaluate our system through a case study visually analyzing prominent MU methods and demonstrate that it helps the user not only understand model behaviors but also gain insights that can inform the improvement of MU methods.
Suhyeon Yu, Yurim Jang, Simon S. Woo, Jaemin Jo
IEEE Trans. Vis. Comput. Graph.5
2025 Waltzboard: Multi-Criteria Automated Dashboard Design for Exploratory Analysis
abstract
We present Waltzboard, an automated dashboard design system for exploratory data analysis. Despite the benefit of dashboards, which provide a glanceable overview of data, previous dashboard design systems often require precomputation, such as training deep-learning models, and do not adapt effectively to changes in the user’s intent during data analysis, hindering quick and flexible data exploration. To overcome these challenges, we introduce a dashboard evaluation framework that quantifies how a dashboard describes data in terms of five key measures: Specificity, Interestingness, Diversity, Coverage, and Parsimony. We then present a three-phase search algorithm designed to efficiently explore dashboard designs without the need for precomputation. Finally, we present a user interface that allows the user to dynamically build their own intent and reason for the design process. The result of our performance benchmark and user study demonstrates that Waltzboard not only designs a more effective dashboard within seconds but also supports flexible exploratory data analysis to meet diverse analytic needs.
Jaemin Jo
PacificVis2
2025 An intelligent marketing platform with influencer classification in social networking services
Xiaohong Yu, Jinyong Kim, Yoseop Ahn, Mose Gu, Jaehoon Jeong 0001, JinYeong Bak, Jaemin Jo
Knowl. Based Syst.7
2025 Visualization-Driven Illumination for Density Plots
abstract
We present a novel visualization-driven illumination model for density plots, a new technique to enhance density plots by effectively revealing the detailed structures in high- and medium-density regions and outliers in low-density regions, while avoiding artifacts in the density field's colors. When visualizing large and dense discrete point samples, scatterplots and dot density maps often suffer from overplotting, and density plots are commonly employed to provide aggregated views while revealing underlying structures. Yet, in such density plots, existing illumination models may produce color distortion and hide details in low-density regions, making it challenging to look up density values, compare them, and find outliers. The key novelty in this work includes (i) a visualization-driven illumination model that inherently supports density-plot-specific analysis tasks and (ii) a new image composition technique to reduce the interference between the image shading and the color-encoded density values. To demonstrate the effectiveness of our technique, we conducted a quantitative study, an empirical evaluation of our technique in a controlled study, and two case studies, exploring twelve datasets with up to two million data point samples.
Xin Chen 0075, Yunhai Wang, Huaiwei Bao, Kecheng Lu 0002, Jaemin Jo, Chi-Wing Fu, Jean-Daniel Fekete
IEEE Trans. Vis. Comput. Graph.5
2025 UMATO: Bridging Local and Global Structures for Reliable Visual Analytics With Dimensionality Reduction
abstract
Due to the intrinsic complexity of high-dimensional (HD) data, dimensionality reduction (DR) techniques cannot preserve all the structural characteristics of the original data. Therefore, DR techniques focus on preserving either local neighborhood structures (local techniques) or global structures such as pairwise distances between points (global techniques). However, both approaches can mislead analysts to erroneous conclusions about the overall arrangement of manifolds in HD data. For example, local techniques may exaggerate the compactness of individual manifolds, while global techniques may fail to separate clusters that are well-separated in the original space. In this research, we provide a deeper insight into Uniform Manifold Approximation with Two-phase Optimization (UMATO), a DR technique that addresses this problem by effectively capturing local and global structures. UMATO achieves this by dividing the optimization process of UMAP into two phases. In the first phase, it constructs a skeletal layout using representative points, and in the second phase, it projects the remaining points while preserving the regional characteristics. Quantitative experiments validate that UMATO outperforms widely used DR techniques, including UMAP, in terms of global structure preservation, with a slight loss in local structure. We also confirm that UMATO outperforms baseline techniques in terms of scalability and stability against initialization and subsampling, making it more effective for reliable HD data analysis. Finally, we present a case study and a qualitative demonstration that highlight UMATO's effectiveness in generating faithful projections, enhancing the overall reliability of visual analytics using DR.
Hyeon Jeon, Kwon Ko, Jake Hyun, Taehyun Yang, Gyehun Go, Jaemin Jo, Jinwook Seo
IEEE Trans. Vis. Comput. Graph.7
2024 Bavisitter: Integrating Design Guidelines into Large Language Models for Visualization Authoring
abstract
Large Language Models (LLMs) have demonstrated remarkable versatility in visualization authoring, but often generate suboptimal designs that are invalid or fail to adhere to design guidelines for effective visualization. We present Bavisitter, a natural language interface that integrates established visualization design guidelines into LLMs. Based on our survey on the design issues in LLM-generated visualizations, Bavisitter monitors the generated visualizations during a visualization authoring dialogue to detect an issue. When an issue is detected, it intervenes in the dialogue, suggesting possible solutions to the issue by modifying the prompts. We also demonstrate two use cases where Bavisitter detects and resolves design issues from the actual LLM-generated visualizations.
Jaemin Jo
IEEE VIS3
2024 GhostUMAP: Measuring Pointwise Instability in Dimensionality Reduction
abstract
Although many dimensionality reduction (DR) techniques employ stochastic methods for computational efficiency, such as negative sampling or stochastic gradient descent, their impact on the projection has been underexplored. In this work, we investigate how such stochasticity affects the stability of projections and present a novel DR technique, GhostUMAP, to measure the pointwise instability of projections. Our idea is to introduce clones of data points, "ghosts", into UMAP’s layout optimization process. Ghosts are designed to be completely passive: they do not affect any others but are influenced by attractive and repulsive forces from the original data points. After a single optimization run, GhostUMAP can capture the projection instability of data points by measuring the variance with the projected positions of their ghosts. We also present a successive halving technique to reduce the computation of GhostUMAP. Our results suggest that Ghost-UMAP can reveal unstable data points with a reasonable computational overhead.
Myeongwon Jung, Takanori Fujiwara, Jaemin Jo
IEEE VIS3
2023 Large-scale Text-to-Image Generation Models for Visual Artists' Creative Works
abstract
Large-scale Text-to-image Generation Models (LTGMs) (e.g., DALL-E), self-supervised deep learning models trained on a huge dataset, have demonstrated the capacity for generating high-quality open-domain images from multi-modal input. Although they can even produce anthropomorphized versions of objects and animals, combine irrelevant concepts in reasonable ways, and give variation to any user-provided images, we witnessed such rapid technological advancement left many visual artists disoriented in leveraging LTGMs more actively in their creative works. Our goal in this work is to understand how visual artists would adopt LTGMs to support their creative works. To this end, we conducted an interview study as well as a systematic literature review of 72 system/application papers for a thorough examination. A total of 28 visual artists covering 35 distinct visual art domains acknowledged LTGMs’ versatile roles with high usability to support creative works in automating the creation process (i.e., automation), expanding their ideas (i.e., exploration), and facilitating or arbitrating in communication (i.e., mediation). We conclude by providing four design guidelines that future researchers can refer to in making intelligent user interfaces using LTGMs.
Hyung-Kwon Ko, Gwanmo Park, Hyeon Jeon, Jaemin Jo, Juho Kim 0001, Jinwook Seo
IUI4
2023 SizePairs: Achieving Stable and Balanced Temporal Treemaps using Hierarchical Size-based Pairing
abstract
We present SizePairs, a new technique to create stable and balanced treemap layouts that visualize values changing over time in hierarchical data. To achieve an overall high-quality result across all time steps in terms of stability and aspect ratio, SizePairs employs a new hierarchical size-based pairing algorithm that recursively pairs two nodes that complement their size changes over time and have similar sizes. SizePairs maximizes the visual quality and stability by optimizing the splitting orientation of each internal node and flipping leaf nodes, if necessary. We also present a comprehensive comparison of SizePairs against the state-of-the-art treemaps developed for visualizing time-dependent data. SizePairs outperforms existing techniques in both visual quality and stability, while being faster than the local moves technique.
Chang Han, Jaemin Jo, Anyi Li, Bongshin Lee, Oliver Deussen, Yunhai Wang
IEEE Trans. Vis. Comput. Graph.2
2023 RCMVis: A Visual Analytics System for Route Choice Modeling
abstract
We present RCMVis, a visual analytics system to support interactive Route Choice Modeling analysis. It aims to model which characteristics of routes, such as distance and the number of traffic lights, affect travelers' route choice behaviors and how much they affect the choice during their trips. Through close collaboration with domain experts, we designed a visual analytics framework for Route Choice Modeling. The framework supports three interactive analysis stages: exploration, modeling, and reasoning. In the exploration stage, we help analysts interactively explore trip data from multiple origin-destination (OD) pairs and choose a subset of data they want to focus on. To this end, we provide coordinated multiple OD views with different foci that allow analysts to inspect, rank, and compare OD pairs in terms of their multidimensional attributes. In the modeling stage, we integrate a k-medoids clustering method and a path-size logit model into our system to enable analysts to model route choice behaviors from trips with support for feature selection, hyperparameter tuning, and model comparison. Finally, in the reasoning stage, we help analysts rationalize and refine the model by selectively inspecting the trips that strongly support the modeling result. For evaluation, we conducted a case study and interviews with domain experts. The domain experts discovered unexpected insights from numerous modeling results, allowing them to explore the hyperparameter space more effectively to gain better results. In addition, they gained OD- and road-level insights into which data mainly supported the modeling result, enabling further discussion of the model.
DongHwa Shin, Jaemin Jo, Bo Hyoung Kim, Hyunjoo Song, Shin-Hyung Cho, Jinwook Seo
IEEE Trans. Vis. Comput. Graph.2
2022 We-toon: A Communication Support System between Writers and Artists in Collaborative Webtoon Sketch Revision
abstract
We present a communication support system, namely We-toon, that can bridge the webtoon writers and artists during sketch revision (i.e., character design and draft revision). In the highly iterative design process between the webtoon writers and artists, writers often have difficulties in precisely articulating their feedback on sketches owing to their lack of drawing proficiency. This drawback makes the writers rely on textual descriptions and reference images found using search engines, leading to indirect and inefficient communications. Inspired by a formative study, we designed We-toon to help writers revise webtoon sketches and effectively communicate with artists. Through a GAN-based image synthesis and manipulation, We-toon can interactively generate diverse reference images and synthesize them locally on any user-provided image. Our user study with 24 professional webtoon authors demonstrated that We-toon outperforms the traditional methods in terms of communication effectiveness and the writers’ satisfaction level related to the revised image.
Hyung-Kwon Ko, Subin An, Gwanmo Park, Seungkwon Kim, Bo Hyoung Kim, Jaemin Jo, Jinwook Seo
UIST7
2022 Measuring and Explaining the Inter-Cluster Reliability of Multidimensional Projections
abstract
We propose Steadiness and Cohesiveness, two novel metrics to measure the inter-cluster reliability of multidimensional projection (MDP), specifically how well the inter-cluster structures are preserved between the original high-dimensional space and the low-dimensional projection space. Measuring inter-cluster reliability is crucial as it directly affects how well inter-cluster tasks (e.g., identifying cluster relationships in the original space from a projected view) can be conducted; however, despite the importance of inter-cluster tasks, we found that previous metrics, such as Trustworthiness and Continuity, fail to measure inter-cluster reliability. Our metrics consider two aspects of the inter-cluster reliability: Steadiness measures the extent to which clusters in the projected space form clusters in the original space, and Cohesiveness measures the opposite. They extract random clusters with arbitrary shapes and positions in one space and evaluate how much the clusters are stretched or dispersed in the other space. Furthermore, our metrics can quantify pointwise distortions, allowing for the visualization of inter-cluster reliability in a projection, which we call a reliability map. Through quantitative experiments, we verify that our metrics precisely capture the distortions that harm inter-cluster reliability while previous metrics have difficulty capturing the distortions. A case study also demonstrates that our metrics and the reliability map 1) support users in selecting the proper projection techniques or hyperparameters and 2) prevent misinterpretation while performing inter-cluster tasks, thus allow an adequate identification of inter-cluster structure.
Hyeon Jeon, Hyung-Kwon Ko, Jaemin Jo, Youngtaek Kim, Jinwook Seo
IEEE Trans. Vis. Comput. Graph.3
2022 Joint t-SNE for Comparable Projections of Multiple High-Dimensional Datasets
abstract
We present Joint t-Stochastic Neighbor Embedding (Joint t-SNE), a technique to generate comparable projections of multiple high-dimensional datasets. Although t-SNE has been widely employed to visualize high-dimensional datasets from various domains, it is limited to projecting a single dataset. When a series of high-dimensional datasets, such as datasets changing over time, is projected independently using t-SNE, misaligned layouts are obtained. Even items with identical features across datasets are projected to different locations, making the technique unsuitable for comparison tasks. To tackle this problem, we introduce edge similarity, which captures the similarities between two adjacent time frames based on the Graphlet Frequency Distribution (GFD). We then integrate a novel loss term into the t-SNE loss function, which we call vector constraints, to preserve the vectors between projected points across the projections, allowing these points to serve as visual landmarks for direct comparisons between projections. Using synthetic datasets whose ground-truth structures are known, we show that Joint t-SNE outperforms existing techniques, including Dynamic t-SNE, in terms of local coherence error, Kullback-Leibler divergence, and neighborhood preservation. We also showcase a real-world use case to visualize and compare the activation of different layers of a neural network.
Yinqiao Wang, Jaemin Jo, Yunhai Wang
IEEE Trans. Vis. Comput. Graph.3
2021 ProReveal: Progressive Visual Analytics With Safeguards
abstract
We present a new visual exploration concept-Progressive Visual Analytics with Safeguards-that helps people manage the uncertainty arising from progressive data exploration. Despite its potential benefits, intermediate knowledge from progressive analytics can be incorrect due to various machine and human factors, such as a sampling bias or misinterpretation of uncertainty. To alleviate this problem, we introduce PVA-Guards, safeguards people can leave on uncertain intermediate knowledge that needs to be verified, and derive seven PVA-Guards based on previous visualization task taxonomies. PVA-Guards provide a means of ensuring the correctness of the conclusion and understanding the reason when intermediate knowledge becomes invalid. We also present ProReveal, a proof-of-concept system designed and developed to integrate the seven safeguards into progressive data exploration. Finally, we report a user study with 14 participants, which shows people voluntarily employed PVA-Guards to safeguard their findings and ProReveal's PVA-Guard view provides an overview of uncertain intermediate knowledge. We believe our new concept can also offer better consistency in progressive data exploration, alleviating people's heterogeneous interpretation of uncertainty.
Jaemin Jo, Sehi L'Yi, Bongshin Lee, Jinwook Seo
IEEE Trans. Vis. Comput. Graph.1
2021 Comparative Layouts Revisited: Design Space, Guidelines, and Future Directions
abstract
We present a systematic review on three comparative layouts-juxtaposition, superposition, and explicit-encoding-which are information visualization (InfoVis) layouts designed to support comparison tasks. For the last decade, these layouts have served as fundamental idioms in designing many visualization systems. However, we found that the layouts have been used with inconsistent terms and confusion, and the lessons from previous studies are fragmented. The goal of our research is to distill the results from previous studies into a consistent and reusable framework. We review 127 research papers, including 15 papers with quantitative user studies, which employed comparative layouts. We first alleviate the ambiguous boundaries in the design space of comparative layouts by suggesting lucid terminology (e.g., chart-wise and item-wise juxtaposition). We then identify the diverse aspects of comparative layouts, such as the advantages and concerns of using each layout in the real-world scenarios and researchers' approaches to overcome the concerns. Building our knowledge on top of the initial insights gained from the Gleicher et al.'s survey [19], we elaborate on relevant empirical evidence that we distilled from our survey (e.g., the actual effectiveness of the layouts in different study settings) and identify novel facets that the original work did not cover (e.g., the familiarity of the layouts to people). Finally, we show the consistent and contradictory results on the performance of comparative layouts and offer practical implications for using the layouts by suggesting trade-offs and seven actionable guidelines.
Sehi L'Yi, Jaemin Jo, Jinwook Seo
IEEE Trans. Vis. Comput. Graph.2
2020 PANENE: A Progressive Algorithm for Indexing and Querying Approximate k-Nearest Neighbors
abstract
We present PANENE, a progressive algorithm for approximate nearest neighbor indexing and querying. Although the use of k-nearest neighbor (KNN) libraries is common in many data analysis methods, most KNN algorithms can only be queried when the whole dataset has been indexed, i.e., they are not online. Even the few online implementations are not progressive in the sense that the time to index incoming data is not bounded and cannot satisfy the latency requirements of progressive systems. This long latency has significantly limited the use of many machine learning methods, such as t-SNE, in interactive visual analytics. PANENE is a novel algorithm for Progressive Approximate k-NEarest NEighbors, enabling fast KNN queries while continuously indexing new batches of data. Following the progressive computation paradigm, PANENE operations can be bounded in time, allowing analysts to access running results within an interactive latency. PANENE can also incrementally build and maintain a cache data structure, a KNN lookup table, to enable constant-time lookups for KNN queries. Finally, we present three progressive applications of PANENE, such as regression, density estimation, and responsive t-SNE, opening up new opportunities to use complex algorithms in interactive systems.
Jaemin Jo, Jinwook Seo, Jean-Daniel Fekete
IEEE Trans. Vis. Comput. Graph.1
2020 Human-Computer Interaction Lab (HCIL) in Seoul National University
abstract
This article introduces Human–Computer Interaction Laboratory (HCIL) established at Seoul National University, Korea, in 2009. We first summarized the history of foundation, achievement, and collaboration for the last 10 years. Then, we delineated our current research directions related to information visualization. Finally, we presented our facilities and equipment to adequately support the research.
GuHyun Han, Jaemin Jo, Han Joo Chae, Jinwook Seo
Vis. Informatics2
2019 Autotator: Semi-Automatic Approach for Accelerating the Chart Image Annotation Process
abstract
Annotating chart images for training machine learning models is tedious and repetitive especially in that chart images often have a large number of visual elements to annotate. We present Autotator, a semi-automatic chart annotation system that automatically provides suggestions for three annotation tasks such as labeling a chart type, annotating bounding boxes, and associating a quantity. We also present a web-based interface that allows users to interact with the suggestions provided by the system. Finally, we demonstrate a use case of our system where an annotator builds a training corpus of bar charts.
Junhoe Kim, Jaemin Jo, Jinwook Seo
ISS2
2019 A Declarative Rendering Model for Multiclass Density Maps
abstract
Multiclass maps are scatterplots, multidimensional projections, or thematic geographic maps where data points have a categorical attribute in addition to two quantitative attributes. This categorical attribute is often rendered using shape or color, which does not scale when overplotting occurs. When the number of data points increases, multiclass maps must resort to data aggregation to remain readable. We present multiclass density maps: multiple 2D histograms computed for each of the category values. Multiclass density maps are meant as a building block to improve the expressiveness and scalability of multiclass map visualization. In this article, we first present a short survey of aggregated multiclass maps, mainly from cartography. We then introduce a declarative model-a simple yet expressive JSON grammar associated with visual semantics-that specifies a wide design space of visualizations for multiclass density maps. Our declarative model is expressive and can be efficiently implemented in visualization front-ends such as modern web browsers. Furthermore, it can be reconfigured dynamically to support data exploration tasks without recomputing the raw data. Finally, we demonstrate how our model can be used to reproduce examples from the past and support exploring data at scale.
Jaemin Jo, Frédéric Vernier, Pierre Dragicevic, Jean-Daniel Fekete
IEEE Trans. Vis. Comput. Graph.1
2018 LongLine: Visual Analytics System for Large-scale Audit Logs
abstract
Audit logs are different from other software logs in that they record the most primitive events (i.e., system calls) in modern operating systems. Audit logs contain a detailed trace of an operating system, and thus have received great attention from security experts and system administrators. However, the complexity and size of audit logs, which increase in real time, have hindered analysts from understanding and analyzing them. In this paper, we present a novel visual analytics system, LongLine, which enables interactive visual analyses of large-scale audit logs. LongLine lowers the interpretation barrier of audit logs by employing human-understandable representations (e.g., file paths and commands) instead of abstract indicators of operating systems (e.g., file descriptors) as well as revealing the temporal patterns of the logs in a multi-scale fashion with meaningful granularity of time in mind (e.g., hourly, daily, and weekly). LongLine also streamlines comparative analysis between interesting subsets of logs, which is essential in detecting anomalous behaviors of systems. In addition, LongLine allows analysts to monitor the system state in a streaming fashion, keeping the latency between log creation and visualization less than one minute. Finally, we evaluate our system through a case study and a scenario analysis with security experts.
Seunghoon Yoo, Jaemin Jo, Bo Hyoung Kim, Jinwook Seo
Vis. Informatics2
2017 SwiftTuna: Responsive and incremental visual exploration of large-scale multidimensional data
abstract
For interactive exploration of large-scale data, a preprocessing scheme (e.g., data cubes) has often been used to summarize the data and provide low-latency responses. However, such a scheme suffers from a prohibitively large amount of memory footprint as more dimensions are involved in querying, and a strong prerequisite that specific data structures have to be built from the data before querying. In this paper, we present SwiftTuna, a holistic system that streamlines the visual information seeking process on large-scale multidimensional data. SwiftTuna exploits an in-memory computing engine, Apache Spark, to achieve both scalability and performance without building precomputed data structures. We also present a novel interactive visualization technique, tailed charts, to facilitate large-scale multidimensional data exploration. To support responsive querying on large-scale data, SwiftTuna leverages an incremental processing approach, providing immediate low-fidelity responses (i.e., prompt responses) as well as delayed high-fidelity responses (i.e., incremental responses). Our performance evaluation demonstrates that SwiftTuna allows data exploration of a real-world dataset with four billion records while preserving the latency between incremental responses within a few seconds.
Jaemin Jo, Wonjae Kim, Seunghoon Yoo, Bo Hyoung Kim, Jinwook Seo
PacificVis1
2017 TouchPivot: Blending WIMP & Post-WIMP Interfaces for Data Exploration on Tablet Devices
abstract
Recent advancements in tablet technology pose a great opportunity for information visualization to expand its horizons beyond desktops. In this paper, we present TouchPivot, a novel interface that assists visual data exploration on tablet devices. With novices in mind, TouchPivot supports data transformations, such as pivoting and filtering, with simple pen and touch interactions, and facilitates understanding of the transformations through tight coupling between a data table and visualization. We bring in WIMP interfaces to TouchPivot, leveraging their familiarity and accessibility to novices. We report on a user study conducted to compare TouchPivot with two commercial interfaces, Tableau and Microsoft Excel's PivotTable. Our results show that novices not only answered data-driven questions faster, but also created a larger number of meaningful charts during freeform exploration with TouchPivot than others. Finally, we discuss the main hurdles novices encountered during our study and possible remedies for them.
Jaemin Jo, Sehi L'Yi, Bongshin Lee, Jinwook Seo
CHI1
2017 CAS: Context-Aware Background Application Scheduling in Interactive Mobile Systems
abstract
Each individual's usage behavior on mobile devices depends on a variety of factors, such as time, location, and previous actions. Hence, context-awareness provides great opportunities to make the networking and computing capabilities of mobile systems more personalized and more efficient in managing their resources. To this end, we first reveal new findings from our own Android user experiment: 1) the launching probabilities of applications follow Zipf's law and 2) inter-running and running times of applications conform to log-normal distributions. We also find contextual dependencies between application usage patterns, for which we classify contexts autonomously with unsupervised learning methods. Using the knowledge acquired, we develop a context-aware application scheduling framework, context-aware application scheduler (CAS), that adaptively unloads and preloads background applications for a joint optimization in which the energy saving is maximized and the user discomfort from the scheduling is minimized. Our trace-driven simulations with 96 user traces demonstrate that the context-aware design of the CAS enables it to outperform existing process scheduling algorithms. Our implementation of the CAS over Android platforms and its end-to-end evaluations verify that its human-involved design indeed provides substantial user-experience gains in both energy and application launching latency.
Kyunghan Lee, Euijin Jeong, Jaemin Jo, Ness Shroff
IEEE J. Sel. Areas Commun.4
2016 Context-aware application scheduling in mobile systems: what will users do and not do next?
abstract
Usage patterns of mobile devices depend on a variety of factors such as time, location, and previous actions. Hence, context-awareness can be the key to make mobile systems to become personalized and situation dependent in managing their resources. We first reveal new findings from our own Android user experiment: (i) the launching probabilities of applications follow Zipf's law, and (ii) inter-running and running times of applications conform to log-normal distributions. We also find context-dependency in application usage patterns, for which we classify contexts in a personalized manner with unsupervised learning methods. Using the knowledge acquired, we develop a novel context-aware application scheduling framework, CAS that adaptively unloads and preloads background applications in a timely manner. Our trace-driven simulations with 96 user traces demonstrate the benefits of CAS over existing algorithms. We also verify the practicality of CAS by implementing it on the Android platform.
Kyunghan Lee, Euijin Jeong, Jaemin Jo, Ness Shroff
UbiComp4
2016 CloakingNote: A Novel Desktop Interface for Subtle Writing Using Decoy Texts
abstract
We present CloakingNote, a novel desktop interface for subtle writing. The main idea of CloakingNote is to misdirect observers' attention away from a real text by using a prominent decoy text. To assess the subtlety of CloakingNote, we conducted a subtlety test while varying the contrast ratio between the real text and its background. Our results demonstrated that the real text as well as the interface itself were subtle even when participants were aware that a writer might be engaged in suspicious activities. We also evaluated the feasibility of CloakingNote through a performance test and categorized the users' layout strategies.
Sehi L'Yi, Kyle Koh, Jaemin Jo, Bo Hyoung Kim, Jinwook Seo
UIST3
2015 EyeBookmark: Assisting Recovery from Interruption during Reading
abstract
In this paper, we present gaze-based bookmarking, EyeBookmark, to mitigate the deleterious effect of interruption during reading. The key idea of EyeBookmark is to provide a visual cue to help people decide where to resume reading. We design four highlighting methods and conduct a controlled user study with a proof-of-concept design to verify the usefulness of EyeBookmark. The user study demonstrates not only that participants preferred our highlighting methods but also that such highlighting methods significantly reduced the time taken to resume reading after interruption regardless of the difficulty of text.
Jaemin Jo, Bo Hyoung Kim, Jinwook Seo
CHI1
2014 LiveGantt: Interactively Visualizing a Large Manufacturing Schedule
abstract
In this paper, we introduce LiveGantt as a novel interactive schedule visualization tool that helps users explore highly-concurrent large schedules from various perspectives. Although a Gantt chart is the most common approach to illustrate schedules, currently available Gantt chart visualization tools suffer from limited scalability and lack of interactions. LiveGantt is built with newly designed algorithms and interactions to improve conventional charts with better scalability, explorability, and reschedulability. It employs resource reordering and task aggregation to display the schedules in a scalable way. LiveGantt provides four coordinated views and filtering techniques to help users explore and interact with the schedules in more flexible ways. In addition, LiveGantt is equipped with an efficient rescheduler to allow users to instantaneously modify their schedules based on their scheduling experience in the fields. To assess the usefulness of the application of LiveGantt, we conducted a case study on manufacturing schedule data with four industrial engineering researchers. Participants not only grasped an overview of a schedule but also explored the schedule from multiple perspectives to make enhancements.
Jaemin Jo, Jaeseok Huh, Bo Hyoung Kim, Jinwook Seo
IEEE Trans. Vis. Comput. Graph.1