Learning Graphical Models
Unsupervised Lexicon Acquisition for HPSG-Based Relation Extraction
Rozenfeld, Benjamin (Digital Trowel) | Feldman, Ronen (Hebrew University of Jerusalem)
The paper describes a method of relation extraction, which is based on parsing the input text using a combination of a generic HPSG-based grammar and a highly focused domain- and relation-specific lexicon. We also show a method of unsupervised acquisition of such a lexicon from a large unlabeled corpus. Together, the methods introduce a novel approach to the “Open IE” task, which is superior in accuracy and in quality of relation identification to the existing approaches.
Unsupervised Lexicon Acquisition for HPSG-Based Relation Extraction
Rozenfeld, Benjamin (Digital Trowel) | Feldman, Ronen (Hebrew University of Jerusalem)
The paper describes a method of relation extraction, which is based on parsing the input text using a combination of a generic HPSG-based grammar and a highly focused domain- and relation-specific lexicon. We also show a method of unsupervised acquisition of such a lexicon from a large unlabeled corpus. Together, the methods introduce a novel approach to the “Open IE” task, which is superior in accuracy and in quality of relation identification to the existing approaches.
From an Agent Logic to an Agent Programming Language for Partially Observable Stochastic Domains
Rens, Gavin Brian (CSIR Meraka Institute)
PODTGolog [Rens, 2010] is a Golog dialect attempting Broadly speaking, my research concerns combining to deal with partially observable MDP (POMDP) logic of action and POMDP theory in a coherent, environments. PODTGolog has not been given a mathematical theoretically sound language for agent programming.
Bayesian Abductive Logic Programs: A Probabilistic Logic for Abductive Reasoning
Raghavan, Sindhu V. (University of Texas at Austin)
In this proposal, we introduce Bayesian Abductive Logic Programs (BALP), a probabilistic logic that adapts Bayesian Logic Programs (BLPs) for abductive reasoning. Like BLPs, BALPs also combine first-order logic and Bayes nets. However, unlike BLPs, which use deduction to construct Bayes nets, BALPs employ logical abduction. As a result, BALPs are more suited for problems like plan/activity recognition that require abductive reasoning. In order to demonstrate the efficacy of BALPs, we apply it to two abductive reasoning tasks — plan recognition and natural language understanding.
Human Behavior Analysis from Video Data Using Bag-of-Gestures
López, Víctor Ponce (University of Barcelona) | López, Mario Gorga (University of Barcelona) | Solé, Xavier Baró (University of Barcelona and Open University of Catalonia) | Guerrero, Sergio Escalera (University of Barcelona and Open University of Catalonia)
Human Behavior Analysis in Uncontrolled Environmentscan be categorized in two main challenges:1) Feature extraction and 2) Behavior analysisfrom a set of corporal language vocabulary. Inthis work, we present our achievements characterizingsome simple behaviors from visual data ondifferent real applications and discuss our plan forfuture work: low level vocabulary definition frombag-of-gesture units and high level modelling andinference of human behaviors.
Towards Scalable MDP Algorithms
Kolobov, Andrey (University of Washington, Seattle)
The scalability of algorithms for solving Markov Decision Processes (MDPs) has been a limiting factor for MDPs as a modeling tool. This dissertation develops theoretical and empirical techniques for solving larger MDPs than was possible before, and aims to demonstrate the achieved progress by applying these new algorithms to a real-world problem.
Control of Robotic Systems for Safe Interaction with Human Operators
Ding, Hao (University of Kassel)
Human Robot Interaction (HRI) is an active field of integrating and embedding different techniques in artificial intelligence. This paper describes my research topic on: Control of Robotic Systems for Safe Interaction with Human Operators. It consists of online motion generation for robotic manipulators interacting with dynamic obstacles and humans using a moving horizon scheme, modeling and long term prediction of human motion using probabilistic models and reachability analysis, and development of an HRI demonstration platform.
Behaviour Recognition in Smart Homes
Chua, Sook-Ling (Massey University) | Marsland, Stephen (Massey University) | Guesgen, Hans W. (Massey University)
Behaviour recognition aims to infer the particular behaviours of the inhabitant in a smart home from a series of sensor readings from around the house. There are many reasons to recognise human behaviours; one being to monitor the elderly or cognitively impaired and detect potentially dangerous behaviours. We view the behaviour recognition problem as the task of mapping the sensory outputs to a sequence of recognised activities. This research focuses on the development of machine learning methods to find an approximation to the mapping between sensor outputs and behaviours. However, learning the mapping raises an important issue, which is that the training data is not necessarily annotated with exemplar behaviours of the inhabitant. This doctoral study takes several steps towards addressing the problem of finding an approximation to this mapping, beginning with separate investigations on current methods proposed in the literature, identifying useful sensory outputs for behaviour recognition, and concluding by proposing two directions: one using supervised learning on annotated sensory stream and one using unsupervised learning on unannotated ones.
Active Exploration for Robust Object Detection
Velez, Javier (Massachusetts Institute of Technology) | Hemann, Garrett (Massachusetts Institute of Technology) | Huang, Albert S. (Massachusetts Institute of Technology) | Posner, Ingmar (Oxford University) | Roy, Nicholas (Massachusetts Institute of Technology)
Today, mobile robots are increasingly expected to operate in ever more complex and dynamic environments.In order to carry out many of the higher level tasks envisioned a semantic understanding of a workspace is pivotal. Here our field has benefited significantly from successes in machine learning and vision: applications in robotics of off-the-shelf object detectors are plentiful. This paper outlines an online, any-time planning framework enabling the active exploration of such detections. Our approach exploits the ability to move to different vantage points and implicitly weighs the benefits of gaining more certainty about the existence of an object against the physical cost of the exploration required. The result is a robot which plans trajectories specifically to decrease the entropy of putative detections. Our system is demonstrated to significantly improve detection performance and trajectory length in simulated and real robot experiments.