规划识别在股票市场中融资行为的研究

规划识别是一种属于心理学和人工智能的交叉学科,能从观察到的某一智能体的动作出发,推导出该智能体规划的过程.将该方法运用到股市中去,通过分析数据并且结合投资者的心理,使投资者做出合理的融资行为.文章提出了由三层模型组成的基于规划识别的融资行为分析算法,在第一层中引入马尔科夫链去预测智能体的行为概率,在第二层中构建规划识别图,进一步预测行为概率,在第三层对智能体的行为进行规划.该算法通过实例进行了验证.     

Controlling inference in plan recognition

An algorithm based on an assessment of the completeness of an explanation can be used to control inference in a plan recognition system: If the explanation is complete, inference is stopped. If the explanation is incomplete, inference is continued. If it cannot be determined whether the explanation is complete, then the system weighs the strength of its interest in continuing the analysis against the estimated cost of doing so. This algorithm places existing heuristic approaches to the control of inference in plan recognition into a unified framework. The algorithm rests on the principle that the decision to continue processing should be based primarily on the explanation chain itself, not on external factors. Only when an analysis of the explanation chain proves inconclusive should outside factors weigh heavily in the decision. Furthermore, a decision to discontinue chaining should never be final; other components of the system should have the opportunity to request that an explanation chain be extended. An implementation of the algorithm, called PAGAN, demonstrates the usefulness of this approach.Dr. James Mayfield is Assistant Professor of Computer Science at the University of Maryland at Baltimore County. He completed his Ph.D. in 1989 at the University of California at Berkeley, under the direction of Dr. Robert Wilensky. His paper reflects his ongoing interest in plan recognition. Dr. Mayfield's other research interests include the detection and resolution of ambiguity, and the automatic conversion of linear text to hypertext.     

Student modelling using plan recognition

Abstract

We present a student modelling approach based on plan recognition methods. In some domains, like theorem proving, the student's activity can be seen as consisting of the formation of plans (the proofs) and the execution of actions (the proof steps). Starting from the student's inputs and the problem's search space, the method infers the most plausible plan according to a criterion of coherence. Recognising the student's plan can help predict his next actions and provide him with well-adapted assistance. This modelling technique is applied in an intelligent tutoring system (ITS) which coaches a student during geometry problem-solving. We describe the architecture of the system: the expert, a set of geometry rules together with a theorem prover which can solve problems in different ways and recognise the student's errors; the interface; and the pedagogical module. Finally, we describe the implemented system and its evaluation.     

A probabilistic plan recognition algorithm based on plan tree grammars

We present the PHATT algorithm for plan recognition. Unlike previous approaches to plan recognition, PHATT is based on a model of plan execution. We show that this clarifies several difficult issues in plan recognition including the execution of multiple interleaved root goals, partially ordered plans, and failing to observe actions. We present the PHATT algorithm's theoretical basis, and an implementation based on tree structures. We also investigate the algorithm's complexity, both analytically and empirically. Finally, we present PHATT's integrated constraint reasoning for parametrized actions and temporal constraints.     

基于智能规划的计划识别模型

为了解决战场态势评估问题,提出了一个基于智能规划的军事计划识别模型,给出了基于一阶谓词逻辑的计划识别模型描述方法,论述了基于该模型的计划假设识别方法。模型可以根据世界模型和作战目标的要求实时生成新的计划,来满足当前计划识别的需要,克服了Kautz计划识别框架的不足。     

Texture recognition via autoregression

This article considers the image processing problem of texture recognition. It is shown that a chi-square test based upon a two-dimensional autoregressive model can be derived and can be used to test for differences between certain types of micro-textures. The chi-square test cannot be used with macro-textures, and another autoregressive-based distance measure is derived which is more suitable for these cases. It is shown experimentally that this distance measure affords a reliable means of classifying a broad class of micro- and macro-textures using a nearest-neighbour type of approach.     

Fuzzy system based human behavior recognition by combining behavior prediction and recognition

With the development of intelligent surveillance systems, human behavior recognition has been extensively researched. Most of the previous methods recognized human behavior based on spatial and temporal features from (current) input image sequences, without the behavior prediction from previously recognized behaviors. Considering an example of behavior prediction, “punching” is more probable in the current frame when the previous behavior is “standing” as compared to the previous behavior being “lying down.” Nevertheless, there has been little study regarding the combination of currently recognized behavior information with behavior prediction. Therefore, we propose a fuzzy system based behavior recognition technique by combining both behavior prediction and recognition. To perform behavior recognition during daytime and nighttime, a dual camera system of visible light and thermal (far infrared light) cameras is used to capture 12 datasets including 11 different human behaviors in various surveillance environments. Experimental results along with the collected datasets and open database showed that the proposed method achieved higher accuracy of behavior recognition when compared to conventional methods.     

Introduction to the special issues on plan recognition

Introduction to the special issues on plan recognition     

Local communication of multiple mobile robots: design of group behavior for efficient communication

A novel design method of robot behavior is discussed to realize efficient local communication for cooperation of multiple mobile robots. Local communication is now increasingly utilized in cooperative many-robot systems because of its advantages of load distribution and simple implementation. In its usage, the design of each robot's behavior is a very important issue since it has a significant effect upon the communication efficiency in a collective manner. In this study, we introduce a simple group behavior and analyze how it improves the performance of local communication among many mobile robots. The performance is evaluated using the information transmission time that plays a crucial part in effective cooperation. Next, the optimal group size is analytically derived by minimizing the transmission time. The effectiveness of the analytical design method is verified by computer simulations of many-robot communication.     

基于稀疏编码的人脸识别算法

介绍了一种基于稀疏编码的人脸识别算法。先对10副自然图像应用稀疏编码,学习到基函数和图像稀疏表示的拟合分布的参数。在人脸识别中,用稀疏编码和已得到的基函数表示图像的稀疏,再经过拟合分布函数得到人脸图像的最终表示,然后应用多分类线性支持向量机（SVM）来完成识别算法。通过在人脸数据库上的实验表明,该算法具有很高的识别正确率。     

On the interaction between plan recognition and intelligent interfaces

Plan recognition is an active research area in automatic reasoning, as well as a promising approach to engineering interfaces that can exploit models of user's plans and goals. Much research in the field has focused on the development of plan recognition algorithms to support particular user/system interactions, such as found in naturally occurring dialogues. However, two questions have typically remained unexamined: 1) exactly what kind of interface tasks can knowledge of a user's plans be used to support across communication modalities, and 2) how can such tasks in turn constrain development of plan recognition algorithms? In this paper we present a concrete exploration of these issues. In particular, we provide an assessment of plan recognition, with respect to the use of plan recognition in enhancing user interfaces. We clarify how use of a user model containing plans makes interfaces more intelligent and interactive (by providing an intelligent assistant that supports such tasks as advice generation, task completion, context-sensitive responses, error detection and recovery). We then show how interface tasks in turn provide constraints that must be satisfied in order for any plan recognizer to construct and represent a plan in ways that efficiently support these tasks. Finally, we survey how interfaces are fundamentally limited by current plan recognition approaches, and use these limitations to identify and motivate current research. Our research is developed in the context of CHECS, a plan-based design interface.     

A meta-rule approach to flexible plan recognition in dialogue

Although a number of researchers have demonstrated that reasoning on a model of the user's plans and goals is helpful in language understanding and response generation, current models of plan inference cannot handle naturally occurring dialogue. This paper argues that model building from less than ideal dialogues has a great deal in common with processing ill-formed input. It defines well-formedness constraints for information-seeking dialogues and contends that strategies for interpreting ill-formed input can be applied to the problem of modeling the user's plan during an ill-formed dialogue. It presents a meta-rule approach for hypothesizing the cause of dialogue ill-formedness, and describes meta-rules for relaxing the plan inference process and enabling the consideration of alternative hypotheses. The advantages of this approach are that it provides a unified framework for handling both well-formed and ill-formed dialogue, avoids unnatural interpretations when the dialogue is proceeding smoothly, and facilitates a nonmonotonic plan recognition system.Rhonda Eller is a Ph.D. candidate in Computer Science at the University of Delaware. She received her B.S. in Computer Science from Millersville University of Pennsylvania in 1987, and her M.S. degree in the same field from the University of Delaware. Her primary interests lie in the areas of natural language processing, plan recognition, and user modelling. This paper summarizes the current state of her thesis work on repair of an incorrectly inferred plan for a user.Sandra Carberry is an associate professor of computer science at the University of Delaware. Her research interests include discourse understanding, user modeling, planning and plan recognition, and intelligent natural language interfaces. This paper describes work that is part of an ongoing research project to develop a robust model of plan recognition.     

Statistical segmentation and structural recognition for floor plan interpretation

A generic method for floor plan analysis and interpretation is presented in this article. The method, which is mainly inspired by the way engineers draw and interpret floor plans, applies two recognition steps in a bottom-up manner. First, basic building blocks, i.e., walls, doors, and windows are detected using a statistical patch-based segmentation approach. Second, a graph is generated, and structural pattern recognition techniques are applied to further locate the main entities, i.e., rooms of the building. The proposed approach is able to analyze any type of floor plan regardless of the notation used. We have evaluated our method on different publicly available datasets of real architectural floor plans with different notations. The overall detection and recognition accuracy is about 95 %, which is significantly better than any other state-of-the-art method. Our approach is generic enough such that it could be easily adopted to the recognition and interpretation of any other printed machine-generated structured documents.     

Lag synchronization analysis of general complex networks with multiple time-varying delays via pinning control strategy

Neural Computing and Applications - This paper focuses on the lag synchronization issue for a kind of general complex networks with multiple time-varying delays via the pinning control strategy. By...     

Forecasting Financial Failure of Firms via Genetic Algorithms

Given a wide amount of possible ratios available for constructing a LOGIT model for forecasting bankruptcy, this paper provides a computational search methodology, only guided by data, for selecting the financial ratios employed in the model. This procedure is based on genetic algorithms which are used to explore the universe of models made available by all possible existing financial ratios (with very redundant information). This search process of the correct model is guided by the Schwarz information criterion. As an empirical illustration, the methodology is applied to forecasting the failure of firms in the Spanish building industry using annual public accounting information.     

Planning multiple observations for object recognition

Most computer vision systems perform object recognition on the basis of the features extracted from a single image of the object. The problem with this approach is that it implicitly assumes that the available features are sufficient to determine the identity and pose of the object uniquely. If this assumption is not met, then the feature set is insufficient, and ambiguity results. Consequently, much research in computer vision has gone toward finding sets of features that are sufficient for specific tasks, with the result that each system has its own associated set of features. A single, general feature set would be desirable. However, research in automatic generation of object recognition programs has demonstrated that predetermined, fixed feature sets are often incapable of providing enough information to unambiguously determine either object identity or pose. One approach to overcoming the inadequacy of any feature set is to utilize multiple sensor observations obtained from different viewpoints, and combine them with knowledge of the 3-D structure of the object to perform unambiguous object recognition. This article presents initial results toward performing object recognition by using multiple observations to resolve ambiguities. Starting from the premise that sensor motions should be planned in advance, the difficulties involved in planning with ambiguous information are discussed. A representation for planning that combines geometric information with viewpoint uncertainty is presented. A sensor planner utilizing the representation was implemented, and the results of pose-determination experiments performed with the planner are discussed.     

Facial expression recognition on multiple manifolds

Manifold learning has been successfully applied to facial expression recognition by modeling different expressions as a smooth manifold embedded in a high dimensional space. However, the assumption of single manifold is still arguable and therefore does not necessarily guarantee the best classification accuracy. In this paper, a generalized framework for modeling and recognizing facial expressions on multiple manifolds is presented which assumes that different expressions may reside on different manifolds of possibly different dimensionalities. The intrinsic features of each expression are firstly learned separately and the genetic algorithm (GA) is then employed to obtain the nearly optimal dimensionality of each expression manifold from the classification viewpoint. Classification is performed under a newly defined criterion that is based on the minimum reconstruction error on manifolds. Extensive experiments on both the Cohn-Kanade and Feedtum databases show the effectiveness of the proposed multiple manifold based approach.     

Face recognition via fast dense correspondence

Face recognition plays a significant role in computer vision. It is well know that facial images are complex stimuli signals that suffer from non-rigid deformations, including misalignment, orientation, pose changes, and variations of facial expression, etc. In order to address these variations, this paper introduces an improved sparse-representation based face recognition method, which constructs dense pixel correspondences between training and testing facial samples. Specifically, we first construct a deformable spatial pyramid graph model that simultaneously regularizes matching consistency at multiple spatial extents - ranging from an entire image, though coarse grid cells, to every single pixel. Secondly, a matching energy function is designed to perform face alignment based on dense pixel correspondence, which is very effective to address the issue of non-rigid deformations. Finally, a novel coarse-to-fine matching scheme is designed so that we are able to speed up the optimization of the matching energy function. After the training samples are aligned with respect to testing samples, an improved sparse representation model is employed to perform face recognition. The experimental results demonstrate the superiority of the proposed method over other methods on ORL, AR, and LFWCrop datasets. Especially, the proposed approach improves nearly 4.4 % in terms of recognition accuracy and runs nearly 10 times faster than previous sparse approximation methods.