1 Context-Linked Virtual Assistants for Distributed Teams: An Astrophysics Case Study Sarah S. Poon Physics Division Space Sciences Lab Berkeley, CA 94720 USA sarahpoon@gmail.com Rollin C. Thomas Physics Division Lawrence Berkeley National Lab Berkeley, CA 94720 USA RCThomas@lbl.gov Cecilia R. Aragon Computational Research Division Lawrence Berkeley National Lab Berkeley, CA 94720 USA CRAragon@lbl.gov Brian Lee Lawrence Berkeley National Lab Gatan Inc. Pleasanton, CA 94588 USA BLee@gatan.com ABSTRACT There is a growing need for distributed teams to analyze complex and dynamic data streams and make critical decisions under time pressure. Via a case study, we discuss potential guidelines for the design of software tools to facilitate such collaborative decision-making. We introduce the term context-linked to characterize systems where both task and context information are included in a shared space. We describe a novel, lightweight, context-linked event notification/virtual assistant system developed to aid a cross-cultural, geographically distributed team of astrophysicists to remotely maneuver a custom-built instrument under challenging operational conditions, where critical decisions must be made in as little as 45 seconds. The system has been in use since 2005 by a major international astrophysics collaboration. We describe the design and implementation of the event notification system and then present a case study, based on event log analysis and user interviews, of its effectiveness in substantially improving user performance during time-critical science tasks. Finally, we discuss the implications of context linking for supporting common ground in distributed teams. Author Keywords Computer-mediated communication, context-aware computing, notification systems, social awareness, collaboratories, cross-cultural collaboration, astrophysics. ACM Classification Keywords H5.3. [Information interfaces and presentation]: Group and organization interfaces–Computer-supported cooperative work. INTRODUCTION In a growing number of operational domains, geographically separated collaborations must collectively make critical decisions under time pressure while evaluating complex, dynamic data streams. First responders, pilots and air traffic controllers, and hospital staff are some common examples. Certain scientific collaborations also fall into this category. Astrophysicists cooperatively operating large telescopes need to monitor complex and ever-changing data while maneuvering equipment under time pressure within tight operational constraints. There is an obvious need for guidelines and examples of collaborative applications to facilitate effective decision- making in such situations. One obstacle to the development of such applications is the difficulty of gaining user acceptance of novel, custom-developed collaborative tools, especially in time-critical domains. For this reason, it makes sense to build lightweight tools that integrate with the existing collaborative environment. Further, such tools must be efficient and effective, providing streamlined, timely access to critical information. Event notification must be appropriately but not overly intrusive. Studies from the aviation domain have demonstrated that scene-linked symbology for head-up displays (synthetic context information projected on a pilot’s cockpit windshield, that appears to be placed within and move with the external physical environment) minimizes inappropriate distractions and provides significant performance advantages [2, 13]. We propose an analogy for computer displays, and define the term context-linked to describe a system where both task information (immediately pertinent to the job at hand) and context information (background processes and events in the environment) are directly included in a shared communication space. In our case, we chose to integrate an event notification system, which provided both task and context information, directly into the tool providing the primary means of team communication. Our lightweight context-linked event notification/virtual assistant system (referred to here as “Bert”) was integrated with an Internet instant messaging (or “chat”) client that had already been accepted by the collaboration. Bert was developed for the Nearby Supernova Factory [1], the largest data volume supernova search currently in operation, processing over 50GB of data per night. There has been little research on software tools for cross- cultural scientific collaborations making critical decisions