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1.
利用构造性学习(CML)算法训练分类器需要大量已标记样本,然而获取大量已标记的样本较为困难。为此,提出了一种协同半监督的构造性学习算法。将已标记样本等分为三个训练集,分别使用构造性学习算法训练三个单分类器,以共同投票的方式对未标记样本进行标记,从而依次扩充三个单分类器训练集直到不能再扩充为止。将三个训练集合并训练出最终的分类器。选取UCI数据集进行实验,结果表明,与CML算法、Tri-CML算法、NB算法及Tri-NB相比,该方法的分类更为有效。  相似文献   

2.
决策树学习算法ID3的研究   总被引:28,自引:0,他引:28  
ID3是决策树学习的核心算法,为此详细叙述了决策树表示方法和ID3决策树学习算法,特别说明了决策属性的选取法则。通过一个学习实例给出该算法第一选取决策属性的详细过程,并且对该算法进行了讨论,一般情况下,ID3算法可以找出最优决策树。  相似文献   

3.
耿传兴  谭正豪  陈松灿 《软件学报》2023,34(4):1870-1878
借助预置任务创建的免费监督信号/标记,自监督学习(SSL)能学得无标记数据的有效表示,并已在多种下游任务中获得了验证.现有预置任务通常先对原视图数据作显式的线性或非线性变换,由此形成了多个增广视图数据,然后通过预测上述视图或变换的对应标记或最大化视图间的一致性达成学习表示.发现这种自监督增广(即数据自身与自监督标记的增广)不仅有益无监督预置任务而且也有益监督分类任务的学习,而当前鲜有工作对此关注,它们要么将预置任务作为下游分类任务的学习辅助,采用多任务学习建模;要么采用多标记学习,联合建模下游任务标记与自监督标记.然而,下游任务与预置任务间往往存在固有差异(语义,任务难度等),由此不可避免地造成二者学习间的竞争,给下游任务的学习带来风险.为挑战该问题,提出一种简单但有效的自监督多视图学习框架(SSL-MV),通过在增广数据视图上执行与下游任务相同的学习来避免自监督标记对下游标记学习的干扰.更有意思的是,借助多视图学习,设计的框架自然拥有了集成推断能力,因而显著提升了下游分类任务的学习性能.最后,基于基准数据集的广泛实验验证了SSL-MV的有效性.  相似文献   

4.
集成学习的多分类器动态组合方法   总被引:2,自引:1,他引:1       下载免费PDF全文
陈冰  张化祥 《计算机工程》2008,34(24):218-220
为了提高数据的分类性能,提出一种集成学习的多分类器动态组合方法(DEA)。该方法在多个UCI标准数据集上进行测试,并与文中使用的基于Adaboost算法训练出的各个成员分类器的分类效果进行比较,证明了DEA的有效性。  相似文献   

5.
经典的证据理论不包括从实例中学习基本信度分配的机制,因此应用范围受到一定限制。通过在证据理论中引入神经网络的学习机制,该文提出了一种有监督学习证据理论分类器。该分类器使用一种经过修改的Widrow-Hoff学习规则从训练实例中学习基本信度分配信息。新实例到来后,该分类器在所学基本信度分配的基础上,使用证据理论合成公式对新实例作分类。新分类器拓展了证据理论的应用领域。实验结果表明该分类器是有效的。  相似文献   

6.
基于分歧的半监督学习   总被引:9,自引:0,他引:9  
周志华 《自动化学报》2013,39(11):1871-1878
传统监督学习通常需使用大量有标记的数据样本作为训练例,而在很多现实问题中,人们虽能容易地获得大批数据样本,但为数据 提供标记却需耗费很多人力物力.那么,在仅有少量有标记数据时,可否通过对大量未标记数据进行利用来提升学习性能呢?为此,半监督学习 成为近十多年来机器学习的一大研究热点.基于分歧的半监督学习是该领域的主流范型之一,它通过使用多个学习器来对未标记数据进行利用, 而学习器间的"分歧"对学习成效至关重要.本文将综述简介这方面的一些研究进展.  相似文献   

7.
提出一种新的基于非监督学习的入侵分析方法.该方法具有发现未知攻击类型的能力,既可以作为独立的分析方法使用,又可以作为基于数据融合的入侵检测的一个分析引擎.在该方法中,核心非监督学习算法采用最大最小距离算法,同时融合非线性的归一化预处理和非数值型特征的有效编码等技术.与同类方法相比,该方法检测率较高,尤其是对于DoS和Probing两大类攻击效果更好.  相似文献   

8.
基于属性组合的集成学习算法   总被引:2,自引:0,他引:2  
针对样本由数字属性构成的分类问题,在AdaBoost算法流程基础上,改传统的基于单属性分类器构造方法为基于组合属性分类器构造方法,提出了一种基于样本属性线性组合的集成学习算法。对属性组合系数的构造,提出了一般性的构造思路,按照该思路,提出了几种具体的组合系数构造方法,并对构造方法的科学合理性进行了分析。利用UCI机器学习数据集中的数据对提出的方法进行了实验与分析,结果表明,基于属性组合的集成学习算法不仅有是有效的,而且比传统AdaBoost算法好  相似文献   

9.
付治  王红军  李天瑞  滕飞  张继 《软件学报》2020,31(4):981-990
聚类是机器学习领域中的一个研究热点,弱监督学习是半监督学习中一个重要的研究方向,有广泛的应用场景.在对聚类与弱监督学习的研究中,提出了一种基于k个标记样本的弱监督学习框架.该框架首先用聚类及聚类置信度实现了标记样本的扩展.其次,对受限玻尔兹曼机的能量函数进行改进,提出了基于k个标记样本的受限玻尔兹曼机学习模型.最后,完成了对该模型的推理并设计相关算法.为了完成对该框架和模型的检验,选择公开的数据集进行对比实验,实验结果表明,基于k个标记样本的弱监督学习框架实验效果较好.  相似文献   

10.
基于单类分类器的半监督学习   总被引:1,自引:0,他引:1  
提出一种结合单类学习器和集成学习优点的Ensemble one-class半监督学习算法.该算法首先为少量有标识数据中的两类数据分别建立两个单类分类器.然后用建立好的两个单类分类器共同对无标识样本进行识别,利用已识别的无标识样本对已建立的两个分类面进行调整、优化.最终被识别出来的无标识数据和有标识数据集合在一起训练一个基分类器,多个基分类器集成在一起对测试样本的测试结果进行投票.在5个UCI数据集上进行实验表明,该算法与tri-training算法相比平均识别精度提高4.5%,与仅采用纯有标识数据的单类分类器相比,平均识别精度提高8.9%.从实验结果可以看出,该算法在解决半监督问题上是有效的.  相似文献   

11.
In this paper we present a new approach for boosting methods for the construction of ensembles of classifiers. The approach is based on using the distribution given by the weighting scheme of boosting to construct a non-linear supervised projection of the original variables, instead of using the weights of the instances to train the next classifier. With this method we construct ensembles that are able to achieve a better generalization error and are more robust to noise presence.It has been proved that AdaBoost method is able to improve the margin of the instances achieved by the ensemble. Moreover, its practical success has been partially explained by this margin maximization property. However, in noisy problems, likely to occur in real-world applications, the maximization of the margin of wrong instances or outliers can lead to poor generalization. We propose an alternative approach, where the distribution of the weights given by the boosting algorithm is used to get a supervised projection. Then, the supervised projection is used to train the next classifier using a uniform distribution of the training instances.The proposed approach is compared with three boosting techniques, namely AdaBoost, GentleBoost and MadaBoost, showing an improved performance on a large set of 55 problems from the UCI Machine Learning Repository, and less sensitiveness to noise in the class labels. The behavior of the proposed algorithm in terms of margin distribution and bias-variance decomposition is also studied.  相似文献   

12.
基于监督学习深度自编码器的图像重构   总被引:1,自引:0,他引:1  
张赛  芮挺  任桐炜  杨成松  邹军华 《计算机科学》2018,45(11):267-271, 297
针对数字图像受损信息的重构问题,提出一种将经典无监督学习自编码器(Auto-Encoder,AE)用于监督学习的新方法,并对深度模型结构与训练策略进行了研究。通过设计多组监督学习单层AE模型,提出了逐组“递进学习”和“关联编码”的学习策略,构建了一个新的基于监督学习的深度AE模型结构;对于新模型结构,采用多对一(一个输入样本的多种形式对应一个输出)的训练方法代替经典AE中一对一(一个输入样本对应一个输出)的训练方法。将该模型的结构和训练策略用于部分数据受损或遮挡的图像中进行数据重构测试,提高了模型对受损数据特征编码的表达能力和重构能力。实验结果表明,提出的新方法对于受损及遮挡样本的图像具有良好的重构效果和适应性。  相似文献   

13.
张莉  孙钢  郭军 《计算机工程》2005,31(13):22-23,45
基于模式识别方法的入侵检测系统首先要解决的一个问题就是特征选择,该文依据数据分布和相关分析两方面,提出了一种基于有监督学习的特征选择方法。根据实验结果可以看出,该算法执行效果较好,且时间复杂性较低。  相似文献   

14.
Supervised tensor learning   总被引:12,自引:1,他引:12  
Tensor representation is helpful to reduce the small sample size problem in discriminative subspace selection. As pointed by this paper, this is mainly because the structure information of objects in computer vision research is a reasonable constraint to reduce the number of unknown parameters used to represent a learning model. Therefore, we apply this information to the vector-based learning and generalize the vector-based learning to the tensor-based learning as the supervised tensor learning (STL) framework, which accepts tensors as input. To obtain the solution of STL, the alternating projection optimization procedure is developed. The STL framework is a combination of the convex optimization and the operations in multilinear algebra. The tensor representation helps reduce the overfitting problem in vector-based learning. Based on STL and its alternating projection optimization procedure, we generalize support vector machines, minimax probability machine, Fisher discriminant analysis, and distance metric learning, to support tensor machines, tensor minimax probability machine, tensor Fisher discriminant analysis, and the multiple distance metrics learning, respectively. We also study the iterative procedure for feature extraction within STL. To examine the effectiveness of STL, we implement the tensor minimax probability machine for image classification. By comparing with minimax probability machine, the tensor version reduces the overfitting problem. We focus on the convex optimization-based binary classification learning algorithms in this paper. This is because the solution to a convex optimization-based learning algorithm is unique. Dacheng Tao received the B.Eng. degree from the University of Science and Technology of China (USTC), the MPhil degree from the Chinese University of Hong Kong (CUHK) and the PhD from the University of London (Birkbeck). He will join the Department of Computing in the Hong Kong Polytechnic University as an assistant professor. His research interests include biometric research, discriminant analysis, support vector machine, convex optimization for machine learning, multilinear algebra, multimedia information retrieval, data mining, and video surveillance. He published extensively at TPAMI, TKDE, TIP, TMM, TCSVT, CVPR, ICDM, ICASSP, ICIP, ICME, ACM Multimedia, ACM KDD, etc. He gained several Meritorious Awards from the Int’l Interdisciplinary Contest in Modeling, which is the highest level mathematical modeling contest in the world, organized by COMAP. He is a guest editor for special issues of the Int’l Journal of Image and Graphics (World Scientific) and the Neurocomputing (Elsevier). Xuelong Li works at the University of London. He has published in journals (IEEE T-PAMI, T-CSVT, T-IP, T-KDE, TMM, etc.) and conferences (IEEE CVPR, ICASSP, ICDM, etc.). He is an Associate Editor of IEEE T-SMC, Part C, Neurocomputing, IJIG (World Scientific), and Pattern Recognition (Elsevier). He is also an Editor Board Member of IJITDM (World Scientific) and ELCVIA (CVC Press). He is a Guest Editor for special issues of IJCM (Taylor and Francis), IJIG (World Scientific), and Neurocomputing (Elsevier). He co-chaired the 5th Annual UK Workshop on Computational Intelligence and the 6th the IEEE Int’l Conf. on Machine Learning and Cybernetics. He was also a publicity chair of the 7th IEEE Int’l Conf. on Data Mining and the 4th Int’l Conf. on Image and Graphics. He has been on the program committees of more than 50 conferences and workshops. Xindong Wu is a Professor and the Chair of the Department of Computer Science at the University of Vermont. He holds a Ph.D. in Artificial Intelligence from the University of Edinburgh, Britain. His research interests include data mining, knowledge-based systems, and Web information exploration. He has published extensively in these areas in various journals and conferences, including IEEE TKDE, TPAMI, ACM TOIS, IJCAI, AAAI, ICML, KDD, ICDM, and WWW, as well as 12 books and conference proceedings. Dr. Wu is the Editor-in-Chief of the IEEE Transactions on Knowledge and Data Engineering (by the IEEE Computer Society), the Founder and current Steering Committee Chair of the IEEE International Conference on Data Mining (ICDM), an Honorary Editor-in-Chief of Knowledge and Information Systems (by Springer), and a Series Editor of the Springer Book Series on Advanced Information and Knowledge Processing (AIKP). He is the 2004 ACM SIGKDD Service Award winner. Weiming Hu received the Ph.D. degree from the Department of Computer Science and Engineering, Zhejiang University. From April 1998 to March 2000, he was a Postdoctoral Research Fellow with the Institute of Computer Science and Technology, Founder Research and Design Center, Peking University. Since April 1998, he has been with the National Laboratory of Pattern Recognition, Institute of Automation, Chinese Academy of Sciences. Now he is a Professor and a Ph.D. Student Supervisor in the laboratory. His research interests are in visual surveillance, neural networks, filtering of Internet objectionable information, retrieval of multimedia, and understanding of Internet behaviors. He has published more than 80 papers on national and international journals, and international conferences. Stephen J. Maybank received a BA in Mathematics from King’s college, Cambridge in 1976 and a PhD in Computer Science from Birkbeck College, University of London in 1988. He was a research scientist at GEC from 1980 to 1995, first at MCCS, Frimley and then, from 1989, at the GEC Marconi Hirst Research Centre in London. In 1995 he became a lecturer in the Department of Computer Science at the University of Reading and in 2004 he became a professor in the School of Computer Science and Information Systems at Birkbeck College, University of London. His research interests include camera calibration, visual surveillance, tracking, filtering, applications of projective geometry to computer vision and applications of probability, statistics and information theory to computer vision. He is the author of more than 90 scientific publications and one book. He is a Fellow of the Institute of Mathematics and its Applications, a Fellow of the Royal Statistical Society and a Senior Member of the IEEE. For further information see http://www.dcs.bbk.ac.uk/~sjmaybank.  相似文献   

15.
This paper addresses a new method for combination of supervised learning and reinforcement learning (RL). Applying supervised learning in robot navigation encounters serious challenges such as inconsistent and noisy data, difficulty for gathering training data, and high error in training data. RL capabilities such as training only by one evaluation scalar signal, and high degree of exploration have encouraged researchers to use RL in robot navigation problem. However, RL algorithms are time consuming as well as suffer from high failure rate in the training phase. Here, we propose Supervised Fuzzy Sarsa Learning (SFSL) as a novel idea for utilizing advantages of both supervised and reinforcement learning algorithms. A zero order Takagi–Sugeno fuzzy controller with some candidate actions for each rule is considered as the main module of robot's controller. The aim of training is to find the best action for each fuzzy rule. In the first step, a human supervisor drives an E-puck robot within the environment and the training data are gathered. In the second step as a hard tuning, the training data are used for initializing the value (worth) of each candidate action in the fuzzy rules. Afterwards, the fuzzy Sarsa learning module, as a critic-only based fuzzy reinforcement learner, fine tunes the parameters of conclusion parts of the fuzzy controller online. The proposed algorithm is used for driving E-puck robot in the environment with obstacles. The experiment results show that the proposed approach decreases the learning time and the number of failures; also it improves the quality of the robot's motion in the testing environments.  相似文献   

16.
无监督主题模型在降维过程中缺少标签信息的指导,丢失一些具有判别性的文本特征,导致最终的分类结果不理想.因此,文中提出结合深度学习的监督主题模型,利用深度网络强大的非线性拟合能力建立文档主题分布与标签之间的映射,利用变分期望最大化(EM)和深度网络训练方法共同完成贝叶斯框架下模型参数的更新,通过改变网络结构和激活函数的类型,用于分类和回归任务.实验表明文中模型既能保持无监督主题模型隐含主题的提取能力,还能更好地完成分类和回归任务.  相似文献   

17.
In multi-instance learning, the training set comprises labeled bags that are composed of unlabeled instances, and the task is to predict the labels of unseen bags. This paper studies multi-instance learning from the view of supervised learning. First, by analyzing some representative learning algorithms, this paper shows that multi-instance learners can be derived from supervised learners by shifting their focuses from the discrimination on the instances to the discrimination on the bags. Second, considering that ensemble learning paradigms can effectively enhance supervised learners, this paper proposes to build multi-instance ensembles to solve multi-instance problems. Experiments on a real-world benchmark test show that ensemble learning paradigms can significantly enhance multi-instance learners.  相似文献   

18.
郑建炜  孔晨辰  王万良  邱虹  章杭科 《计算机科学》2016,43(6):312-315, 324
通过将鉴别邻域嵌入分析算法扩展到非线性场景,提出了一种有监督核化邻域投影分析算法。该算法在目标函数中引入类别标签和线性投影矩阵,并利用核函数处理非线性数据。通过两种不同策略优化目标函数,可将该算法进一步细分为有监督核化邻域投影分析算法一及有监督核化邻域投影分析算法二。其中,在有监督核化邻域投影分析算法一中应用拉普拉斯搜索方向达到了较快的收敛速度并降低了计算复杂度。实验结果表明,所提算法对于复杂的数据流形具有较高的识别率,且与鉴别邻域嵌入分析等相关算法相比在有效性和鲁棒性方面的表现更为出色。  相似文献   

19.
针对流形学习算法——局部保持映射存在的参数选择及不能进行非线性特征提取的问题,提出一种基于核的监督流形学习算法.该算法作为局部保持映射算法的改进算法用样本类标识信息指导建立局部最近邻图,并在建立局部最近邻图使用无参数的相似度量.利用核方法来解决局部保持映射算法在处理线性不可分问题上的局限性问题.在两个常用数据库上验证本文算法的可行性和有效性.  相似文献   

20.
A Knowledge-Intensive Genetic Algorithm for Supervised Learning   总被引:7,自引:0,他引:7  
Janikow  Cezary Z. 《Machine Learning》1993,13(2-3):189-228
  相似文献   

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