Goto

Collaborating Authors

 Problem Solving


Human-In-The-Loop Learning of Qualitative Preference Models

arXiv.org Artificial Intelligence

In this work, we present a novel human-in-the-loop framework to help the human user understand the decision making process that involves choosing preferred options. We focus on qualitative preference models over alternatives from combinatorial domains. This framework is interactive: the user provides her behavioral data to the framework, and the framework explains the learned model to the user. It is iterative: the framework collects feedback on the learned model from the user and tries to improve it accordingly till the user terminates the iteration. In order to communicate the learned preference model to the user, we develop visualization of intuitive and explainable graphic models, such as lexicographic preference trees and forests, and conditional preference networks. To this end, we discuss key aspects of our framework for lexicographic preference models.


Extracting Conceptual Knowledge from Natural Language Text Using Maximum Likelihood Principle

arXiv.org Artificial Intelligence

Domain-specific knowledge graphs constructed from natural language text are ubiquitous in today's world. In many such scenarios the base text, from which the knowledge graph is constructed, concerns itself with practical, on-hand, actual or ground-reality information about the domain. Product documentation in software engineering domain are one example of such base texts. Other examples include blogs and texts related to digital artifacts, reports on emerging markets and business models, patient medical records, etc. Though the above sources contain a wealth of knowledge about their respective domains, the conceptual knowledge on which they are based is often missing or unclear. Access to this conceptual knowledge can enormously increase the utility of available data and assist in several tasks such as knowledge graph completion, grounding, querying, etc. Our contributions in this paper are twofold. First, we propose a novel Markovian stochastic model for document generation from conceptual knowledge. The uniqueness of our approach lies in the fact that the conceptual knowledge in the writer's mind forms a component of the parameter set of our stochastic model. Secondly, we solve the inverse problem of learning the best conceptual knowledge from a given document, by finding model parameters which maximize the likelihood of generating the specific document over all possible parameter values. This likelihood maximization is done using an application of Baum-Welch algorithm, which is a known special case of Expectation-Maximization (EM) algorithm. We run our conceptualization algorithm on several well-known natural language sources and obtain very encouraging results. The results of our extensive experiments concur with the hypothesis that the information contained in these sources has a well-defined and rigorous underlying conceptual structure, which can be discovered using our method.


Encoding Selection for Solving Hamiltonian Cycle Problems with ASP

arXiv.org Artificial Intelligence

Answer Set Programming (ASP) [3] has been shown to be especia lly effective on search and optimization problems whose decision versions are in the class NP, includ ing many problems of practical interest [9, 6]. Despite the ease of modeling and the demonstrated pot ential of ASP, using it poses challenges. In particular, it is unlikely a single solver will emerge tha t would uniformly outperform other solvers. Consequently, selecting a solver for an instance may mean th e difference between solving the problem within an acceptable time and having the solver run "forever ." To address the problem, solver selection, portfolio solving, and automated solver parameter configur ation have all been extensively studied [17, 10, 14, 16, 12].


SAT Solvers and Computer Algebra Systems: A Powerful Combination for Mathematics

arXiv.org Artificial Intelligence

Over the last few decades, many distinct lines of research aimed at automating mathematics have been developed, including computer algebra systems (CASs) for mathematical modelling, automated theorem provers for first-order logic, SAT/SMT solvers aimed at program verification, and higher-order proof assistants for checking mathematical proofs. More recently, some of these lines of research have started to converge in complementary ways. One success story is the combination of SAT solvers and CASs (SAT+CAS) aimed at resolving mathematical conjectures. Many conjectures in pure and applied mathematics are not amenable to traditional proof methods. Instead, they are best addressed via computational methods that involve very large combinatorial search spaces. SAT solvers are powerful methods to search through such large combinatorial spaces---consequently, many problems from a variety of mathematical domains have been reduced to SAT in an attempt to resolve them. However, solvers traditionally lack deep repositories of mathematical domain knowledge that can be crucial to pruning such large search spaces. By contrast, CASs are deep repositories of mathematical knowledge but lack efficient general search capabilities. By combining the search power of SAT with the deep mathematical knowledge in CASs we can solve many problems in mathematics that no other known methods seem capable of solving. We demonstrate the success of the SAT+CAS paradigm by highlighting many conjectures that have been disproven, verified, or partially verified using our tool MathCheck. These successes indicate that the paradigm is positioned to become a standard method for solving problems requiring both a significant amount of search and deep mathematical reasoning. For example, the SAT+CAS paradigm has recently been used by Heule, Kauers, and Seidl to find many new algorithms for $3\times3$ matrix multiplication.


Solving Service Robot Tasks: UT Austin Villa@Home 2019 Team Report

arXiv.org Artificial Intelligence

RoboCup@Home is an international robotics competition based on domestic tasks requiring autonomous capabilities pertaining to a large variety of AI technologies. Research challenges are motivated by these tasks both at the level of individual technologies and the integration of subsystems into a fully functional, robustly autonomous system. We describe the progress made by the UT Austin Villa 2019 RoboCup@Home team which represents a significant step forward in AI-based HRI due to the breadth of tasks accomplished within a unified system. Presented are the competition tasks, component technologies they rely on, our initial approaches both to the components and their integration, and directions for future research.


The Role of AI in Industry: UoB Business Club Breakfast Briefing

#artificialintelligence

Join UoB Business Club for valuable insight into applications of Artificial Intelligence (AI) in industry and discover the support available from the University of Birmingham and the Science & Technologies Facilities Council to businesses seeking to investigate potential applications of AI in their processes. Complimentary breakfast is included in this free event. Mohan is a Senior Lecturer in the School of Computer Science. His primary research interests include knowledge representation and reasoning, machine learning, computer vision and cognitive systems as applied to autonomous robots and adaptive agents. Mohan develops architectures and algorithms that enable robots to collaborate with non-expert human participants, acquiring and using sensor inputs and high-level human feedback based on need and availability.


Developing Computational Models of Social Assistance to Guide Socially Assistive Robots

arXiv.org Artificial Intelligence

While there are many examples in which robots provide social assistance, a lack of theory on how the robots should decide how to assist impedes progress in realizing these technologies. To address this deficiency, we propose a pair of computational models to guide a robot as it provides social assistance. The model of social autonomy helps a robot select an appropriate assistance that will help with the task at hand while also maintaining the autonomy of the person being assisted. The model of social alliance describes how a to determine whether the robot and the person being assisted are cooperatively working towards the same goal. Each of these models are rooted in social reasoning between people, and we describe here our ongoing work to adapt this social reasoning to human-robot interactions. Socially assistive robots (SARs) provide social assistance instead of physically intervening.


Abstraction for Zooming-In to Unsolvability Reasons of Grid-Cell Problems

arXiv.org Artificial Intelligence

Humans are capable of abstracting away irrelevant details when studying problems. This is especially noticeable for problems over grid-cells, as humans are able to disregard certain parts of the grid and focus on the key elements important for the problem. Recently, the notion of abstraction has been introduced for Answer Set Programming (ASP), a knowledge representation and reasoning paradigm widely used in problem solving, with the potential to understand the key elements of a program that play a role in finding a solution. The present paper takes this further and empowers abstraction to deal with structural aspects, and in particular with hierarchical abstraction over the domain. We focus on obtaining the reasons for unsolvability of problems on grids, and show the possibility to automatically achieve human-like abstractions that distinguish only the relevant part of the grid. A user study on abstract explanations confirms the similarity of the focus points in machine vs. human explanations and reaffirms the challenge of employing abstraction to obtain machine explanations.


Allen Institute for AI Announces BERT-Breakthrough: Passing an 8th-Grade Science Exam - NVIDIA Developer News Center

#artificialintelligence

This week the Allen Institute for Artificial Intelligence announced a breakthrough for a BERT-based model, passing an eighth-grade science test. The GPU-accelerated system called Aristo can read, learn, and reason about science, in this case emulating the decision making of students. For this milestone, Aristo answered more than 90 percent of the questions on an eighth-grade science exam correctly, and 83 percent on a 12th-grade exam. "Although Aristo only answers multiple choice questions without diagrams, and operates only in the domain of science, it nevertheless represents an important milestone towards systems that can read and understand," the researchers stated in a newly published paper on ArXiv. "The momentum on this task has been remarkable, with accuracy moving from roughly 60% to over 90% in just three years," Though no diagrams were used for this particular task, the work as a whole integrates multiple AI-based technologies including natural language processing, information extraction, knowledge representation and reasoning, commonsense knowledge, and diagram understanding.


The Well-Grounded Rubyist [PDF] - Programmer Books

#artificialintelligence

In this chapter, we'll explore Ruby's facilities for pattern matching and text processing, centering around the use of regular expressions. A regular expression in Ruby serves the same purposes it does in other languages: it specifies a pattern of characters, a pattern that may or may not correctly predict (that is, match) a given string. Pattern-match operations are used for conditional branching (match/no match), pinpointing substrings (parts of a string that match parts of the pattern), and various text-filtering techniques. Regular expressions in Ruby are objects. You send messages to a regular expression.