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Load Balancing for Hypertable

AAAI Conferences

In Hypertable ranges of table data are stored and accessed on different nodes and allows for flexible management of the underlying hardware. Overall performance is sensitive to the balance of range load across the cluster. The project developers aim to create a simple interface to allow researchers to design experimental load balancing strategies that incorporate machine learning and optimization. This paper specifies the load balancing problem and introduces it as a challenge problem for AI and machine learning.


Embodied Language Processing: A New Generation of Language Technology

AAAI Conferences

At a computational level, language processing tasks are traditionally processed in a language-only space/context, isolated from perception and action. However, at a cognitive level, language processing has been shown experimentally to be embodied, i.e. to inform and be informed by perception and action. In this paper, we argue that embodied cognition dictates the development of a new generation of language processing tools that bridge the gap between the symbolic and the sensorimotor representation spaces. We describe that tasks and challenges such tools need to address and provide an overview of the first such suite of processing tools developed in the framework of the POETICON project.


Defining the Complexity of an Activity

AAAI Conferences

Activity recognition is a widely researched area with applications in health care, security and other domains. With each recognition system considering its own set of activities and sensors, it is difficult to compare the performance of these different systems and more importantly it makes the task of selecting an appropriate set of technologies and tools for recognizing an activity challenging. In this work-in-progress paper we attempt to characterize activities in terms of a complexity measure. We define activity complexity along three dimensions – sensing, computation and performance and illustrate different parameters that parameterize these dimensions. We look at grammars for representing activities and use grammar complexity as a measurement for activity complexity. Then we describe how these measurements can help evaluate the complexity of activities of daily living that are commonly considered by various researchers.


Multi-Fisheye for Interactive Visualization of Large Graphs

AAAI Conferences

By selectively zooming in and zooming out visualizations, the fisheye technique allows users to study details while maintaining context. In this paper, weintroduce a multi-fisheye technique, which amounts to introducing several fisheyes in a visualization at the same time. Our multi-fisheye technique isbased on partitioning the visualization's display area and applying a fisheye algorithm inside each partition. While we demonstrate the potential ofapplying our multi-fisheye technique using a social network, it clearly can be applied in other areas and types of networks, including in probabilisticgraphical models such as Bayesian networks.


On Quality Control and Machine Learning in Crowdsourcing

AAAI Conferences

The advent of crowdsourcing has created a variety of new opportunities for improving upon traditional methods of data collection and annotation. This in turn has created intriguing new opportunities for data-driven machine learning (ML). Convenient access to crowd workers for simple data collection has further generalized to leveraging more arbitrary crowd-based human computation (von Ahn 2005) to supplement automated ML. While new potential applications of crowdsourcing continue to emerge, a variety of practical and sometimes unexpected obstacles have already limited the degree to which its promised potential can be actually realized in practice. This paper considers two particular aspects of crowdsourcing and their interplay, data quality control (QC) and ML, reflecting on where we have been, where we are, and where we might go from here.


Position Paper: Embracing Heterogeneity—Improving Energy Efficiency for Interactive Services on Heterogeneous Data Center Hardware

AAAI Conferences

Data centers today are heterogeneous: they have servers from multiple generations and multiple vendors; server machines have multiple cores that are capable of running at difference speeds, and some have general purpose graphics processing units (GPGPU). Hardware trends indicate that future processors will have heterogeneous cores with different speeds and capabilities. This environment enables new advances in power saving and application optimization. It also poses new challenges, as current systems software is ill-suited for heterogeneity. In this position paper, we focus on interactive applications and outline some of the techniques to embrace heterogeneity. We show that heterogeneity can be exploited to deliver interactive services in an energy-efficient manner. For example, our initial study suggests that neither high-end nor low-end servers alone are very effective in servicing a realistic workload, which typically has requests with varying service demands. High-end servers achieve good throughput but the energy costs are high. Low-end servers are energy-efficient for short requests, but they may not be able to serve long requests at the desired quality of service. In this work, we show that a heterogeneous system can be a better choice than an equivalent homogeneous system to deliver interactive services in a cost-effective manner, transforming heterogeneity from a resource management nightmare to an asset. We highlight some of the challenges and opportunities and the role of AI and machine learning techniques for hosting large interactive services in data centers.


Agent Based Intelligent Decluttering Enhancements

AAAI Conferences

Model-driven visualization (MDV) is a novel framework that supports more effective, intelligent user interfaces to improve decision making in complex environments by coupling cognitive and perceptual theories of information processing with advanced artificial intelligence methods. It embeds empirical and theory driven approaches for identifying and prioritizing data based on the information requirements and needs of the human decision maker within intelligent agents. The agents automatically deliver and present information based on its likely value using visualizations that best convey that information to the user(s) of the system. Agents also reason about the context and constraints of the user, environment, and display to enable a higher degree of personalization within an interactive user interface (e.g., by drawing a user’s attention to interesting aspects of the data such as trends, anomalies, and patterns). We apply cognitive systems engineering processes to help identify the information available to individuals and/or teams, where it resides, where it is needed, and ultimately how to create the mappings required in connecting critical information to those who need it with innovative visualizations that most effectively support the end user. This paper describes the application of MDV to intelligently deliver timely, mission-critical information by adapting a Common Tactical Picture (CTP) display used for maritime situation awareness, threat assessment, and decision support.


Leadership Games and their Application in Super-Peer Networks

AAAI Conferences

This paper considers a setting where a single ``leadership agent'' intervenes in a multi-agent system through actions that (perhaps subtly) change the dynamics of the system. We describe a number of forms this intervention can take and compare these situations to settings in previous work. We identify two important effects of leadership: faster system convergence, and convergence to a better equilibrium. Empirically, we first explore these properties in leadership of algorithms engaged in classical 2-player games. We then apply this general framework to the leadership of a super-peer file-sharing network. In these experiments the network contains some agents that make locally greedy decisions that hamper the network as a whole. We show that a leader acting based on a more global criteria can push the system to a better equilibrium point as well as speeding up convergence. We also show how a mathematical approximation of such super-peer networks can be used to aid a leader in determining a minimum-cost intervention strategy.


Towards Task Recommendation in Micro-Task Markets

AAAI Conferences

As researchers embrace micro-task markets for eliciting human input, the nature of the posted tasks moves from those requiring simple mechanical labor to requiring specific cognitive skills. On the other hand, increase is seen in the number of such tasks and the user population in microtask market places requiring better search interfaces for productive user participation. In this paper we posit that understanding user skill sets and pre- senting them with suitable tasks not only maximizes the over quality of the output, but also attempts to maximize the benefit to the user in terms of more successfully completed tasks. We also implement a recommendation engine for suggesting tasks to users based on implicit modeling of skills and interests. We present results from a preliminary evaluation of our system using publicly available data gathered from a variety of human computation experiments recently conducted on Amazon’s Mechanical Turk.


Towards Detection of Suspicious Behavior from Multiple Observations

AAAI Conferences

This paper addresses the problem of detecting suspicious behavior from a collection of individuals events, where no single event is enough to decide whether his/her behavior is suspicious, but the combination of multiple events enables reasoning. We establish a Bayesian framework for evaluating multiple events and show that the current approaches lack modeling behavior history included in the estimation whether a trace of events is generated by a suspicious agent. We propose a heuristic for evaluating events according to the behavior of the agent in the past. The proposed approach, tested on an airport domain, outperforms the current approaches.