Ricky J. Sethi

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The demand for advanced skills in data analysis spans many areas of science, computing, and business analytics. This paper discusses how non-expert users reuse workflows created by experts and representing complex data mining processes for text analytics. They include workflows for document classification, document clustering, and topic detection, all(More)
In this paper, we focus on the problem of searching for complex activities involving multiple, interacting objects in video. We examine the dynamics of formation and dispersal of groups as well as their interactions with other groups and individuals. In order to establish a general formalism, we examine activities using relative distances in phase space via(More)
In this paper, we propose a computational framework for integrating the physics of motion with the neurobiological basis of perception in order to model and recognize human actions and object activities. The essence, or gist, of an action is intrinsically related to the motion of the scene's objects. We define the Hamiltonian Energy Signature (HES) and(More)
Understanding group activities is an essential step towards studying complex crowd behaviours in video. However, such research is often hampered by the lack of a formal definition of a group, as well as a dearth of datasets that concentrate specifically on Atomic Group Actions. <sup>1</sup> In this paper, we provide a quantitative definition of a group(More)
This paper concentrates on the problem of modelling and recognition of complex behaviours involving multi-object interactions in video. We use motion patterns of individual objects to construct models which characterize pairs by correlating them in phase space. These models of complex interactions allow for: recognition of group activities, which occur when(More)
Activity recognition is a field of computer vision which has shown great progress in the past decade. Starting from simple single person activities, research in activity recognition is moving toward more complex scenes involving multiple objects and natural environments. The main challenges in the task include being able to localize and recognize events in(More)
Semantic wikis augment wikis with semantic properties that can be used to aggregate and query data through reasoning. Semantic wikis are used by many communities, for widely varying purposes such as organizing genomic knowledge, coding software, and tracking environmental data. Although wikis have been analyzed extensively, there has been no published(More)
In this paper, we propose an innovative approach for the development of social collaboration argumentation systems. These systems enable a community to collaboratively create answers to questions where many possible answers, or nuanced perspectives on a single answer, can be posited. We examine the emergence of critical reasoning via crowdsourced structured(More)
In this paper, we demonstrate the ability to reuse workflow fragments in different data domains: from text analytics to image analysis to video activity recognition. We highlight how the re-use of workflows allows scientists to link across disciplines and avail themselves of the benefits of interdisciplinary research beyond their normal area of expertise.(More)