VLDB 2026 Research / reviewers in the wild / expert
Savvas Petridis
dblp:185/5665 · also Savvas Dimitrios Petridis
· DBLP profile ↗
12ranked-venue papers
8as first author
10since 2021 · last 2026
0000-0002-4944-8477ORCID · verified
Domains — the database's venue-derived domains; a paper can count in several
Human-computer interaction and ubiquitous computing · 11 · 8 first-author · 9 since 2021Artificial intelligence and machine learning · 1 · 1 since 2021
| Year | Publication | Venue | Position |
|---|---|---|---|
| 2026 | Compass vs Railway Tracks: Unpacking User Mental Models for Communicating Long-Horizon Work to Humans vs. AIabstractAs agentic AI systems grow increasingly capable of operating for hours or days at a time, users’ prompts are transforming into highly elaborate specifications for the AI to autonomously work on. While prompting for bounded, single-turn tasks has been extensively studied, less is known about how people communicate specifications for long-horizon tasks. In this work, we conducted a qualitative study in which 16 professionals drafted specifications for both a human colleague and an AI, revealing a core divergence: participants treated human delegation as a “compass,” offering high-level intent to encourage flexible exploration. In contrast, communication with AI resembled painstakingly laying down “railway tracks”: rigid, exhaustive instructions to minimize ambiguity and deviation. This reflected a perception that current AI struggles to infer intent, prioritize, and make judgments on its own. When envisioning an ideal AI collaborator, users expressed a desire for a hybrid : a collaborator blending AI’s efficiency and large context window with the critical thinking and agency of a human colleague. We discuss design implications for future AI systems, proposing that they align on outcomes through generated rough drafts, verify feasibility via end-to-end “test runs,” and monitor execution through intelligent check-ins—ultimately transforming AI from a passive instruction-follower into a reliable collaborator for ambiguous, long-horizon tasks. Savvas Petridis, Michael Xieyang Liu, Alexander Fiannaca, Carrie J. Cai, Michael Terry |
DIS | 1 |
| 2025 | Gensors: Authoring Personalized Visual Sensors with Multimodal Foundation Models and ReasoningabstractMultimodal large language models (MLLMs), with their expansive world knowledge and reasoning capabilities, present a unique opportunity for end-users to create personalized AI sensors capable of reasoning about complex situations. A user could describe a desired sensing task in natural language (e.g., "alert if my toddler is getting into mischief"), with the MLLM analyzing the camera feed and responding within seconds. In a formative study, we found that users saw substantial value in defining their own sensors, yet struggled to articulate their unique personal requirements and debug the sensors through prompting alone. To address these challenges, we developed Gensors, a system that empowers users to define customized sensors supported by the reasoning capabilities of MLLMs. Gensors 1) assists users in eliciting requirements through both automatically-generated and manually created sensor criteria, 2) facilitates debugging by allowing users to isolate and test individual criteria in parallel, 3) suggests additional criteria based on user-provided images, and 4) proposes test cases to help users "stress test" sensors on potentially unforeseen scenarios. In a user study, participants reported significantly greater sense of control, understanding, and ease of communication when defining sensors using Gensors. Beyond addressing model limitations, Gensors supported users in debugging, eliciting requirements, and expressing unique personal requirements to the sensor through criteria-based reasoning; it also helped uncover users' "blind spots" by exposing overlooked criteria and revealing unanticipated failure modes. Finally, we discuss how unique characteristics of MLLMs--such as hallucinations and inconsistent responses--can impact the sensor-creation process. These findings contribute to the design of future intelligent sensing systems that are intuitive and customizable by everyday users. Michael Xieyang Liu, Savvas Petridis, Vivian Tsai, Alexander Fiannaca, Alex Olwal, Michael Terry, Carrie J. Cai |
IUI | 2 |
| 2025 | Position: Towards Bidirectional Human-AI AlignmentabstractRecent advances in general-purpose AI underscore the urgent need to align AI systems with human goals and values. Yet, the lack of a clear, shared understanding of what constitutes "alignment" limits meaningful progress and cross-disciplinary collaboration. In this position paper, we argue that the research community should explicitly define and critically reflect on "alignment" to account for the bidirectional and dynamic relationship between humans and AI. Through a systematic review of over 400 papers spanning HCI, NLP, ML, and more, we examine how alignment is currently defined and operationalized. Building on this analysis, we introduce the Bidirectional Human-AI Alignment framework, which not only incorporates traditional efforts to align AI with human values but also introduces the critical, underexplored dimension of aligning humans with AI – supporting cognitive, behavioral, and societal adaptation to rapidly advancing AI technologies. Our findings reveal significant gaps in current literature, especially in long-term interaction design, human value modeling, and mutual understanding. We conclude with three central challenges and actionable recommendations to guide future research toward more nuanced, reciprocal, and human-AI alignment approaches. Hua Shen 0005, Tiffany Knearem, Reshmi Ghosh, Kenan Alkiek, Kundan Krishna, Yachuan Liu, Savvas Petridis, Yi-Hao Peng, Li Qiwei, Chenglei Si, Yutong Xie 0007, Jeffrey P. Bigham, Frank Bentley, Joyce Y. Chai, Zachary C. Lipton, Qiaozhu Mei, Michael Terry, Diyi Yang, Meredith Ringel Morris, Paul Resnick, David Jurgens |
NeurIPS | 7 |
| 2024 | PromptInfuser: How Tightly Coupling AI and UI Design Impacts Designers' WorkflowsabstractPrototyping AI applications is notoriously difficult. While large language model (LLM) prompting has dramatically lowered the barriers to AI prototyping, designers are still prototyping AI functionality and UI separately. We investigate how coupling prompt and UI design affects designers’ workflows. Grounding this research, we developed PromptInfuser, a Figma plugin that enables users to create semi-functional mockups, by connecting UI elements to the inputs and outputs of prompts. In a study with 14 designers, we compare PromptInfuser to designers’ current AI-prototyping workflow. PromptInfuser was perceived to be significantly more useful for communicating product ideas, more capable of producing prototypes that realistically represent the envisioned artifact, more efficient for prototyping, and more helpful for anticipating UI issues and technical constraints. PromptInfuser encouraged iteration over prompt and UI together, which helped designers identify UI and prompt incompatibilities and reflect upon their total solution. Together, these findings inform future systems for prototyping AI applications. Savvas Petridis, Michael Terry, Carrie J. Cai |
Conference on Designing Interactive Systems | 1 |
| 2024 | ConstitutionMaker: Interactively Critiquing Large Language Models by Converting Feedback into PrinciplesabstractLarge language model (LLM) prompting is a promising new approach for users to create and customize their own chatbots. However, current methods for steering a chatbot’s outputs, such as prompt engineering and fine-tuning, do not support users in converting their natural feedback on the model’s outputs to changes in the prompt or model. In this work, we explore how to enable users to interactively refine model outputs through their feedback, by helping them convert their feedback into a set of principles (i.e. a constitution) that dictate the model’s behavior. From a formative study, we (1) found that users needed support converting their feedback into principles for the chatbot and (2) classified the different principle types desired by users. Inspired by these findings, we developed ConstitutionMaker, an interactive tool for converting user feedback into principles, to steer LLM-based chatbots. With ConstitutionMaker, users can provide either positive or negative feedback in natural language, select auto-generated feedback, or rewrite the chatbot’s response; each mode of feedback automatically generates a principle that is inserted into the chatbot’s prompt. In a user study with 14 participants, we compare ConstitutionMaker to an ablated version, where users write their own principles. With ConstitutionMaker, participants felt that their principles could better guide the chatbot, that they could more easily convert their feedback into principles, and that they could write principles more efficiently, with less mental demand. ConstitutionMaker helped users identify ways to improve the chatbot, formulate their intuitive responses to the model into feedback, and convert this feedback into specific and clear principles. Together, these findings inform future tools that support the interactive critiquing of LLM outputs. Savvas Petridis, Benjamin D. Wedin, James Wexler, Mahima Pushkarna, Aaron Donsbach, Nitesh Goyal, Carrie J. Cai, Michael Terry |
IUI | 1 |
| 2024 | In Situ AI Prototyping: Infusing Multimodal Prompts into Mobile Settings with MobileMakerabstractRecent advances in multimodal large language models (LLMs) have made it easier to rapidly prototype AI-powered features, especially for mobile use cases. However, gathering early, mobile-situated user feedback on these AI prototypes remains challenging. The broad scope and flexibility of LLMs means that, for a given use-case-specific prototype, there is a crucial need to understand the wide range of in-the-wild input users are likely to provide and their in-context expectations for the AI’s behavior. To explore the concept of in situ AI prototyping and testing, we created MobileMaker: a platform that enables designers to rapidly create and test mobile AI prototypes directly on devices. This tool also enables testers to make on-device, in-the-field revisions of prototypes using natural language. In an exploratory study with 16 participants, we explored how user feedback on prototypes created with MobileMaker compares to that of existing prototyping tools (e.g., Figma, prompt editors). Our findings suggest that MobileMaker prototypes enabled more serendipitous discovery of: model input edge cases, discrepancies between AI’s and user’s in-context interpretation of the task, and contextual signals missed by the AI. Furthermore, we learned that while the ability to make in-the-wild revisions led users to feel more fulfilled as active participants in the design process, it might also constrain their feedback to the subset of changes perceived as more actionable or implementable by the prototyping tool. Savvas Petridis, Michael Xieyang Liu, Alexander Fiannaca, Vivian Tsai, Michael Terry, Carrie J. Cai |
VL/HCC | 1 |
| 2023 | AngleKindling: Supporting Journalistic Angle Ideation with Large Language ModelsabstractNews media often leverage documents to find ideas for stories, while being critical of the frames and narratives present. Developing angles from a document such as a press release is a cognitively taxing process, in which journalists critically examine the implicit meaning of its claims. Informed by interviews with journalists, we developed AngleKindling, an interactive tool which employs the common sense reasoning of large language models to help journalists explore angles for reporting on a press release. In a study with 12 professional journalists, we show that participants found AngleKindling significantly more helpful and less mentally demanding to use for brainstorming ideas, compared to a prior journalistic angle ideation tool. AngleKindling helped journalists deeply engage with the press release and recognize angles that were useful for multiple types of stories. From our findings, we discuss how to help journalists customize and identify promising angles, and extending AngleKindling to other knowledge-work domains. Savvas Petridis, Nicholas Diakopoulos, Kevin Crowston, Mark Hansen, Keren Henderson, Stan Jastrzebski, Jeffrey V. Nickerson, Lydia B. Chilton |
CHI | 1 |
| 2023 | PopBlends: Strategies for Conceptual Blending with Large Language ModelsabstractPop culture is an important aspect of communication. On social media people often post pop culture reference images that connect an event, product or other entity to a pop culture domain. Creating these images is a creative challenge that requires finding a conceptual connection between the users’ topic and a pop culture domain. In cognitive theory, this task is called conceptual blending. We present a system called PopBlends that automatically suggests conceptual blends. The system explores three approaches that involve both traditional knowledge extraction methods and large language models. Our annotation study shows that all three methods provide connections with similar accuracy, but with very different characteristics. Our user study shows that people found twice as many blend suggestions as they did without the system, and with half the mental demand. We discuss the advantages of combining large language models with knowledge bases for supporting divergent and convergent thinking. Sitong Wang 0001, Savvas Petridis, Taeahn Kwon, Xiaojuan Ma, Lydia B. Chilton |
CHI | 2 |
| 2022 | TastePaths: Enabling Deeper Exploration and Understanding of Personal Preferences in Recommender SystemsabstractRecommender systems are ubiquitous and influence the information we consume daily by helping us navigate vast catalogs of information like music databases. However, their linear approach of surfacing content in ranked lists limits their ability to help us grow and understand our personal preferences. In this paper, we study how we can better support users in exploring a novel space, specifically focusing on music genres. Informed by interviews with expert music listeners, we developed TastePaths: an interactive web tool that helps users explore an overview of the genre-space via a graph of connected artists. We conducted a comparative user study with 16 participants where each of them used a personalized version of TastePaths (built with a set of artists the user listens to frequently) and a non-personalized one (based on a set of the most popular artists in a genre). We find that participants employed various strategies to explore the space. Overall, they greatly preferred the personalized version as it helped anchor their exploration and provided recommendations that were more compatible with their personal taste. In addition to that, TastePaths helped participants specify and articulate their interest in the genre and gave them a better understanding of the system’s organization of music. Based on our findings, we discuss opportunities and challenges for incorporating more control and expressive feedback in recommendation systems to help users explore spaces beyond their immediate interests and improve these systems’ underlying algorithms. Savvas Petridis, Nediyana Daskalova, Sarah Mennicken, Samuel F. Way, Paul Lamere, Jennifer Thom-Santelli |
IUI | 1 |
| 2021 | SymbolFinder: Brainstorming Diverse Symbols Using Local Semantic NetworksabstractVisual symbols are the building blocks for visual communication. They convey abstract concepts like reform and participation quickly and effectively. When creating graphics with symbols, novice designers often struggle to brainstorm multiple, diverse symbols because they fixate on a few associations instead of broadly exploring different aspects of the concept. We present SymbolFinder, an interactive tool for finding visual symbols for abstract concepts. SymbolFinder molds symbol-finding into a recognition rather than recall task by introducing the user to diverse clusters of words associated with the concept. Users can dive into these clusters to find related, concrete objects that symbolize the concept. We evaluate SymbolFinder with two studies: a comparative user study, demonstrating that SymbolFinder helps novices find more unique symbols for abstract concepts with significantly less effort than a popular image database and a case study demonstrating how SymbolFinder helped design students create visual metaphors for three cover illustrations of news articles. Savvas Petridis, Hijung Shin, Lydia B. Chilton |
UIST | 1 |
| 2019 | Human Errors in Interpreting Visual MetaphorabstractVisual metaphors are a creative technique used in print media to convey a message through images. This message is not said directly, but implied through symbols and how those symbols are juxtaposed in the image. The messages we see affect our thoughts and lives, and it is an open research challenge to get machines to automatically understand the implied messages in images. However, it is unclear how people process these images or to what degree they understand the meaning. We test several theories about how people interpret visual metaphors and find people can interpret the visual metaphor correctly without explanatory text with 41.3% accuracy. We provide evidence for four distinct types of errors people make in their interpretation, which speaks to the cognitive processes people use to infer the meaning. We also show that people's ability to interpret a visual message is not simply a function of image content but also of message familiarity. This implies that efforts to automatically understand visual images should take into account message familiarity. Savvas Petridis, Lydia B. Chilton |
Creativity & Cognition | 1 |
| 2019 | VisiBlends: A Flexible Workflow for Visual BlendsabstractVisual blends are an advanced graphic design technique to draw attention to a message. They combine two objects in a way that is novel and useful in conveying a message symbolically. This paper presents VisiBlends, a flexible workflow for creating visual blends that follows the iterative design process. We introduce a design pattern for blending symbols based on principles of human visual object recognition. Our workflow decomposes the process into both computational techniques and human microtasks. It allows users to collaboratively generate visual blends with steps involving brainstorming, synthesis, and iteration. An evaluation of the workflow shows that decentralized groups can generate blends in independent microtasks, co-located groups can collaboratively make visual blends for their own messages, and VisiBlends improves novices' ability to make visual blends. Lydia B. Chilton, Savvas Petridis, Maneesh Agrawala |
CHI | 2 |