Asia
Modeling Social Causality and Responsibility Judgment in Multi-Agent Interactions
Social causality is the inference an entity makes about the social behavior of other entities and self. Besides physical cause and effect, social causality involves reasoning about epistemic states of agents and coercive circumstances. Based on such inference, responsibility judgment is the process whereby one singles out individuals to assign responsibility, credit or blame for multi-agent activities. Social causality and responsibility judgment are a key aspect of social intelligence, and a model for them facilitates the design and development of a variety of multi-agent interactive systems. Based on psychological attribution theory, this paper presents a domain-independent computational model to automate social inference and judgment process according to an agents causal knowledge and observations of interaction. We conduct experimental studies to empirically validate the computational model. The experimental results show that our model predicts human judgments of social attributions and makes inferences consistent with what most people do in their judgments. Therefore, the proposed model can be generically incorporated into an intelligent system to augment its social and cognitive functionality.
Improving Statistical Machine Translation for a Resource-Poor Language Using Related Resource-Rich Languages
We propose a novel language-independent approach for improving machine translation for resource-poor languages by exploiting their similarity to resource-rich ones. More precisely, we improve the translation from a resource-poor source language X_1 into a resource-rich language Y given a bi-text containing a limited number of parallel sentences for X_1-Y and a larger bi-text for X_2-Y for some resource-rich language X_2 that is closely related to X_1. This is achieved by taking advantage of the opportunities that vocabulary overlap and similarities between the languages X_1 and X_2 in spelling, word order, and syntax offer: (1) we improve the word alignments for the resource-poor language, (2) we further augment it with additional translation options, and (3) we take care of potential spelling differences through appropriate transliteration. The evaluation for Indonesian- >English using Malay and for Spanish -> English using Portuguese and pretending Spanish is resource-poor shows an absolute gain of up to 1.35 and 3.37 BLEU points, respectively, which is an improvement over the best rivaling approaches, while using much less additional data. Overall, our method cuts the amount of necessary "real'' training data by a factor of 2--5.
A Mixed Integer Programming Model Formulation for Solving the Lot-Sizing Problem
Mohammadi, Maryam, Tap, Masine Md.
This paper addresses a mixed integer programming (MIP) formulation for the multi-item uncapacitated lot-sizing problem that is inspired from the trailer manufacturer. The proposed MIP model has been utilized to find out the optimum order quantity, optimum order time, and the minimum total cost of purchasing, ordering, and holding over the predefined planning horizon. This problem is known as NP-hard problem. The model was presented in an optimal software form using LINGO 13.0.
Stochastic Belief Propagation: A Low-Complexity Alternative to the Sum-Product Algorithm
Noorshams, Nima, Wainwright, Martin J.
The sum-product or belief propagation (BP) algorithm is a widely-used message-passing algorithm for computing marginal distributions in graphical models with discrete variables. At the core of the BP message updates, when applied to a graphical model with pairwise interactions, lies a matrix-vector product with complexity that is quadratic in the state dimension $d$, and requires transmission of a $(d-1)$-dimensional vector of real numbers (messages) to its neighbors. Since various applications involve very large state dimensions, such computation and communication complexities can be prohibitively complex. In this paper, we propose a low-complexity variant of BP, referred to as stochastic belief propagation (SBP). As suggested by the name, it is an adaptively randomized version of the BP message updates in which each node passes randomly chosen information to each of its neighbors. The SBP message updates reduce the computational complexity (per iteration) from quadratic to linear in $d$, without assuming any particular structure of the potentials, and also reduce the communication complexity significantly, requiring only $\log{d}$ bits transmission per edge. Moreover, we establish a number of theoretical guarantees for the performance of SBP, showing that it converges almost surely to the BP fixed point for any tree-structured graph, and for graphs with cycles satisfying a contractivity condition. In addition, for these graphical models, we provide non-asymptotic upper bounds on the convergence rate, showing that the $\ell_{\infty}$ norm of the error vector decays no slower than $O(1/\sqrt{t})$ with the number of iterations $t$ on trees and the mean square error decays as $O(1/t)$ for general graphs. These analysis show that SBP can provably yield reductions in computational and communication complexities for various classes of graphical models.
Algorithms and Limits for Compact Plan Representations
Compact representations of objects is a common concept in computer science. Automated planning can be viewed as a case of this concept: a planning instance is a compact implicit representation of a graph and the problem is to find a path (a plan) in this graph. While the graphs themselves are represented compactly as planning instances, the paths are usually represented explicitly as sequences of actions. Some cases are known where the plans always have compact representations, for example, using macros. We show that these results do not extend to the general case, by proving a number of bounds for compact representations of plans under various criteria, like efficient sequential or random access of actions. In addition to this, we show that our results have consequences for what can be gained from reformulating planning into some other problem. As a contrast to this we also prove a number of positive results, demonstrating restricted cases where plans do have useful compact representations, as well as proving that macro plans have favourable access properties. Our results are finally discussed in relation to other relevant contexts.
A Model-Theoretic Semantics for Two-Sided Argumentation
Wang, Geng (Peking University) | Lin, Zuoquan (Peking University)
Argumentation is a natural meaning of reasoning in the daily life, and has also become a highly interested topic of knowledge representation in the past few years. In this paper, we will use the phrase "two-sided argumentation" for a type of formalization for our real world debate: an issue with a pro-side supports it and a con-side opposes it. Then, we will point out that, when we use the term "argumentation," we in fact mean a binary concept: a method of reasoning, and a type of negotiation. For both case, we will consider the semantics: argumentative models for the former, argumentation games for the latter. We will also give out some results about the relationship between them.
Asymptotic Maximum Entropy Principle for Utility Elicitation under High Uncertainty and Partial Information
Hadfi, Rafik (Nagoya Institute of Technology) | Ito, Takayuki (Nagoya Institute of Technology)
Decision making has proposed multiple methods to help the decision maker in his analysis, by suggesting ways of formalization of the preferences as well as the assessment of the uncertainties. Although these techniques are established and proven to be mathematically sound, experience has shown that in certain situations we tend to avoid the formal approach by acting intuitively. Especially, when the decision involves a large number of attributes and outcomes, and where we need to use pragmatic and heuristic simplifications such as considering only the most important attributes and omitting the others. In this paper, we provide a model for decision making in situations subject to a large predictive uncertainty with a small learning sample. The high predictive uncertainty is concretized by a countably infinite number of prospects, making the preferences assessment more difficult. Our main result is an extension of the Maximum Entropy utility (MEU) principle into an asymptotic maximum entropy utility principle for preferences elicitation. This will allow us to overcome the limits of the existing MEU method to the extend that we focus on utility assessment when the set of the available discrete prospects is countably infinite. Furthermore, our proposed model can be used to analyze situations of high-cognitive load as well as to understand how humans handle these problems under Ceteris Paribus assumption.
Snackbot: The Process to Engage in Human-Robot Conversation
Moon, Dekita (Fort Valley State University) | Rybski, Paul (Carnegie Mellon University ) | Swanier, Cheryl (Fort Valley State University) | Boonthum-Denecke, Chutima (Hampton University)
While delivering snacks, Snackbot’s need to actively engage in conversation with the customers and other individuals, provides an approach for verbal interaction. This paper addresses the verbal human-robot interaction between humans and robots using a speech recognizer named Sphinx-4. Sphinx-4, written entirely in Java is capable of recognizing predetermined words and sentences. Thereby, allowing robots to actively engage in conversations using spoken language.
Leg Design for a Praying Mantis Robot
Cardona, Ramon A. (Interamerican University of Puerto Rico) | Touretzky, David S. (Carnegie Mellon University)
The praying mantis uses its front legs for locomotion, prey capture and feeding. Inspired by this dexterity, we began designing a hexapod robot that could use its front legs for both locomotion and manipulation. Our current work focuses on the middle and back legs of the robot. We designed a five degree of freedom leg, using a gimbal to form three intersecting axes of rotation at the hip to imitate a ball-and-socket joint. There is also a one degree of freedom knee, and an unpowered ankle joint. A key requirement for the design is to provide for standing postures in which the robot can support itself without putting any load on the leg servos. This will increase servo life span. We simulated the leg by constructing a 3D model in SolidWorks, then importing that model into the Mirage simulator, part of the Tekkotsu robotics framework. A functioning prototype was then built using Robotis Dynamixel RX-64 servos. This was a geometrically simplified version of the original model, but it retained every motor capability of the original design. We tested the prototype using two types of pre-specified motion sequences, with good results.
Mining Data from Project LISTEN’s Reading Tutor to Analyze Development of Children's Oral Reading Prosody
Sitaram, Sunayana (Carnegie Mellon University) | Mostow, Jack (Carnegie Mellon University)
Reading tutors can provide an unprecedented opportunity to collect and analyze large amounts of data for understanding how students learn. We trained models of oral reading prosody (pitch, intensity, and duration) on a corpus of narrations of 4558 sentences by 11 fluent adults. We used these models to evaluate the oral reading prosody of 85,209 sentences read by 55 children (mostly) 7-10 years old who used Project LISTEN's Reading Tutor during the 2005-2006 school year. We mined the resulting data to pinpoint the specific common syntactic and lexical features of text that children scored best and worst on. These features predict their fluency and comprehension test scores and gains better than previous models. Focusing on these features may help human or automated tutors improve children’s fluency and comprehension more effectively.