arXiv subjects

Kartik Talamadupula

Publications and source records attributed to Kartik Talamadupula.

40 records · Page 3Linked to original sources

arXiv2014

The Metrics Matter! On the Incompatibility of Different Flavors of Replanning

When autonomous agents are executing in the real world, the state of the world as well as the objectives of the agent may change from the agent's original model. In such cases, the agent's planning process must modify the plan under execution to make it amenable to the new conditions, and to resume execution. This brings up the replanning problem, and the various techniques that have been proposed to solve it. In all, three main techniques -- based on three different metrics -- have been proposed in prior automated planning work. An open question is whether these metrics are interchangeable; answering this requires a normalized comparison of the various replanning quality metrics. In this paper, we show that it is possible to support such a comparison by compiling all the respective techniques into a single substrate. Using this novel compilation, we demonstrate that these different metrics are not interchangeable, and that they are not good surrogates for each other. Thus we focus attention on the incompatibility of the various replanning flavors with each other, founded in the differences between the metrics that they respectively seek to optimize.

cs.AI↗

arXiv2013

RAProp: Ranking Tweets by Exploiting the Tweet/User/Web Ecosystem and Inter-Tweet Agreement

The increasing popularity of Twitter renders improved trustworthiness and relevance assessment of tweets much more important for search. However, given the limitations on the size of tweets, it is hard to extract measures for ranking from the tweets' content alone. We present a novel ranking method, called RAProp, which combines two orthogonal measures of relevance and trustworthiness of a tweet. The first, called Feature Score, measures the trustworthiness of the source of the tweet. This is done by extracting features from a 3-layer twitter ecosystem, consisting of users, tweets and the pages referred to in the tweets. The second measure, called agreement analysis, estimates the trustworthiness of the content of the tweet, by analyzing how and whether the content is independently corroborated by other tweets. We view the candidate result set of tweets as the vertices of a graph, with the edges measuring the estimated agreement between each pair of tweets. The feature score is propagated over this agreement graph to compute the top-k tweets that have both trustworthy sources and independent corroboration. The evaluation of our method on 16 million tweets from the TREC 2011 Microblog Dataset shows that for top-30 precision we achieve 53% higher than current best performing method on the Dataset and over 300% over current Twitter Search. We also present a detailed internal empirical evaluation of RAProp in comparison to several alternative approaches proposed by us.

cs.IR↗

arXiv2013

Herding the Crowd: Automated Planning for Crowdsourced Planning

There has been significant interest in crowdsourcing and human computation. One subclass of human computation applications are those directed at tasks that involve planning (e.g. travel planning) and scheduling (e.g. conference scheduling). Much of this work appears outside the traditional automated planning forums, and at the outset it is not clear whether automated planning has much of a role to play in these human computation systems. Interestingly however, work on these systems shows that even primitive forms of automated oversight of the human planner does help in significantly improving the effectiveness of the humans/crowd. In this paper, we will argue that the automated oversight used in these systems can be viewed as a primitive automated planner, and that there are several opportunities for more sophisticated automated planning in effectively steering crowdsourced planning. Straightforward adaptation of current planning technology is however hampered by the mismatch between the capabilities of human workers and automated planners. We identify two important challenges that need to be overcome before such adaptation of planning technology can occur: (i) interpreting the inputs of the human workers (and the requester) and (ii) steering or critiquing the plans being produced by the human workers armed only with incomplete domain and preference models. In this paper, we discuss approaches for handling these challenges, and characterize existing human computation systems in terms of the specific choices they make in handling these challenges.

cs.AI↗

arXiv2013

Strategic Planning for Network Data Analysis

As network traffic monitoring software for cybersecurity, malware detection, and other critical tasks becomes increasingly automated, the rate of alerts and supporting data gathered, as well as the complexity of the underlying model, regularly exceed human processing capabilities. Many of these applications require complex models and constituent rules in order to come up with decisions that influence the operation of entire systems. In this paper, we motivate the novel "strategic planning" problem -- one of gathering data from the world and applying the underlying model of the domain in order to come up with decisions that will monitor the system in an automated manner. We describe our use of automated planning methods to this problem, including the technique that we used to solve it in a manner that would scale to the demands of a real-time, real world scenario. We then present a PDDL model of one such application scenario related to network administration and monitoring, followed by a description of a novel integrated system that was built to accept generated plans and to continue the execution process. Finally, we present evaluations of two different automated planners and their different capabilities with our integrated system, both on a six-month window of network data, and using a simulator.

cs.AI↗