Dynamic selection of classifiers—A comprehensive review

This work presents a literature review of multiple classifier systems based on the dynamic selection of classifiers. First, it briefly reviews some basic concepts and definitions related to such a classification approach and then it presents the state of the art organized according to a proposed taxonomy. In addition, a two-step analysis is applied to the results of the main methods reported in the literature, considering different classification problems. The first step is based on statistical analyses of the significance of these results. The idea is to figure out the problems for which a significant contribution can be observed in terms of classification performance by using a dynamic selection approach. The second step, based on data complexity measures, is used to investigate whether or not a relation exists between the possible performance contribution and the complexity of the classification problem. From this comprehensive study, we observed that, for some classification problems, the performance contribution of the dynamic selection approach is statistically significant when compared to that of a single-based classifier. In addition, we found evidence of a relation between the observed performance contribution and the complexity of the classification problem. These observations allow us to suggest, from the classification problem complexity, that further work should be done to predict whether or not to use a dynamic selection approach.     

多分类器系统的泛组合规则研究与应用

现有的多分类器系统采用固定的组合算子,适用性较差。将泛逻辑的柔性化思想引入多分类器系统中,应用泛组合运算模型建立了泛组合规则。泛组合规则采用遗传算法进行参数估计,对并行结构的多分类器系统具有良好的适用性。在时间序列数据集上的分类实验结果表明,泛组合规则的分类性能优于乘积规则、均值规则、中值规则、最大规则、最小规则、投票规则等固定组合规则。     

An accuracy-oriented self-splitting fuzzy classifier with support vector learning in high-order expanded consequent space

This paper proposes a self-splitting fuzzy classifier with support vector learning in expanded high-order consequent space (SFC-SVHC) for classification accuracy improvement. The SFC-SVHC expands the rule-mapped consequent space of a first-order Takagi-Sugeno (TS)-type fuzzy system by including high-order terms to enhance the rule discrimination capability. A novel structure and parameter learning approach is proposed to construct the SFC-SVHC. For structure learning, a variance-based self-splitting clustering (VSSC) algorithm is used to determine distributions of the fuzzy sets in the input space. There are no rules in the SFC-SVHC initially. The VSSC algorithm generates a new cluster by splitting an existing cluster into two according to a predefined cluster-variance criterion. The SFC-SVHC uses trigonometric functions to expand the rule-mapped first-order consequent space to a higher-dimensional space. For parameter optimization in the expanded rule-mapped consequent space, a support vector machine is employed to endow the SFC-SVHC with high generalization ability. Experimental results on several classification benchmark problems show that the SFC-SVHC achieves good classification results with a small number of rules. Comparisons with different classifiers demonstrate the superiority of the SFC-SVHC in classification accuracy.     

权重自适应调整的多分类器集成判决及其在文本分类中的应用

1 引言近年来,多分类器的组合方法已成为模式识别研究的热点问题,并已在模式识别的多个应用方面,如字符识别、目标识别、文本分类等领域获得了较好的应用效果。多分类器组合方法的基本假设是:对一个需要专家进行的任务,k个专家个人判断的有效组合应该优于个人的判断。利用具有不同特性和性能的多分类器,通过进行有效的组合可以获得更高的模式识别性能。     

基于选择性集成分类器的面部表情识别研究*

为了提高面部表情的分类识别性能,基于集成学习理论,提出了一种二次优化选择性(Quadratic Optimization Choice, QOC)集成分类模型。首先,对于9个基分类器,依据性能进行排序,选择前30%的基分类器作为集成模型的候选基分类器。其次,依据组合规则产生集成模型簇。最后,对集成模型簇进行二次优化选择,选择具有最小泛化误差的集成分类器的子集,从而确定最优集成分类模型。为了验证QOC集成分类模型的性能,选择采用最大值、最小值和均值规则的集成模型作为对比模型,实验结果表明：相对基分类器,QOC集成分类模型取得了较好的分类效果,尤其是对于识别率较差的悲伤表情类,平均识别率提升了21.11%。相对于非选择性集成模型,QOC集成分类模型识别性能也有显著提高。     

基于正负模糊规则的相结合的图像分类

由于传统的图像分类只是利用正模糊规则对图像分类,忽略了负模糊规则在图像分类中的作用。据此本文提出用正负模糊规则的相结的方法对图像进行分类,注重将负模糊规则和传统的正模糊分类规则有效结合。实验表明,该方法有较高的准确率,获得了更好的效果。     

A method of combining multiple probabilistic classifiers through soft competition on different feature sets

A novel method is proposed for combining multiple probabilistic classifiers on different feature sets. In order to achieve the improved classification performance, a generalized finite mixture model is proposed as a linear combination scheme and implemented based on radial basis function networks. In the linear combination scheme, soft competition on different feature sets is adopted as an automatic feature rank mechanism so that different feature sets can be always simultaneously used in an optimal way to determine linear combination weights. For training the linear combination scheme, a learning algorithm is developed based on Expectation–Maximization (EM) algorithm. The proposed method has been applied to a typical real-world problem, viz., speaker identification, in which different feature sets often need consideration simultaneously for robustness. Simulation results show that the proposed method yields good performance in speaker identification.     

一种模糊规则提取方法的研究

提出了一种基于改进的模糊 C 均值聚类的模糊规则提取方法。然后基于所提取的模糊规则给出了一种分类算法,并利用 IRIS 数据对此分类算法进行了仿真测试。结果表明,该算法在训练祥本较少的情况下,仍能得到很好的分类效果,由此说明所提出的模糊规则生成方法有效。     

辐射源识别的模糊联想分类器设计

The fuzzy associative classifier is investigated in this paper. The design methods of the fuzzy associative classifier with genetic algorithm for training are presented. This method trains the weight and back terms to obtain classification rules automatically. Radar radiant points are classified by using of this algorithm, and the simulation results show that the method has higher identification precision than available fuzzy classifiers.     

Designing of classifiers based on immune principles and fuzzy rules

This paper proposed an algorithm to design a fuzzy classification system based on immune principles. The proposed algorithm evolves a population of antibodies based on the clonal selection and hypermutation principles. The membership function parameters and the fuzzy rule set including the number of rules inside it are evolved at the same time. Each antibody (candidate solution) corresponds to a fuzzy classification rule set. We compared our algorithm with other classification schemes on some benchmark datasets. The results demonstrated the effectiveness of the proposed immune algorithm.     

Neuro-fuzzy approach versus rough-set inspired methodology for intelligent decision support

One of the two goals of this paper is to briefly present two different methodologies that can be used to the design of intelligent decision support systems, in particular, from the field of medicine. The first approach, combining artificial neural networks and fuzzy sets, yields a neuro-fuzzy classifier that can be trained with both purely numerical data as well as qualitative, linguistic, fuzzy data that describe the decision-making process. The second approach – resulting in a rough classifier – combines all positive aspects of rule induction systems with the flexibility of statistical techniques for classification. The second goal of this paper is to perform a broad comparative analysis of both proposed methodologies (and two others) applied to: (a) the problem of selecting surgical and non-surgical cases in the veterinary domain of equine colic, (b) the problem of diagnosing benign and malign types of breast cancer, and (c) the problem of corporate bankruptcy prediction (corporate ‘financial health'). Several aspects of comparison have been considered including the accuracy of the systems, diversity of the data processed, transparency and the form of decisions made.     

基于协同进化算法的高维模糊分类系统的设计

基于协同进化算法,提出一种高维模糊分类系统的设计方法．首先定义系统的精确性指标,给出解释性的必要条件,利用聚类算法辨识初始模型．相互协作的3类种群分别代表系统的特征变量、规则前件和模型隶属函数的参数,适应度函数采用3类种群合作计算的策略,在算法运行中利用基于相似性的模型简化技术约简模糊系统,最后利用该方法对Wine问题进行研究．仿真结果表明该方法能够对高维分类问题的特征变量进行选择,同时利用较少规则和模糊集合数达到较高的识别率．     

一种基于模糊规则的分类方法

本文提出了一种基于模糊规则的分类方法。首先介绍了一种新的模糊规则提取方法，然后基于所提取的模糊规则给出了一个采用二级判决的分类算法，并利用IRIS数据对此分类算法进行了仿真测试。结果表明，该算法在训练样本较少的情况下，仍能得到很好的分类效果.     

基于Boosting算法集成遗传模糊分类器的文本分类

提出一种新颖的基于Boosting模糊分类的文本分类方法。首先采用潜在语义索引(LSI)对文本特征进行选择;然后提出Boosting算法集成模糊分类器学习,在每轮迭代训练过程中,算法通过调整训练样本的分布,利用遗传算法产生分类规则。减少分类规则能够正确分类样本的权值,使得新产生的分类规则重点考虑难于分类的样本。实验结果表明,该文本分类算法具有良好分类的性能。     

On-line evolving image classifiers and their application to surface inspection

In this paper, we present image classifiers which are able to adapt and evolve themselves at an on-line machine vision system. These classifiers are initially trained on some pre-labelled training data and further updated based on newly recorded samples, for instance during a production process. The evolution and adaptation mechanism is necessary in order to guarantee a process-save on-line system as usually the pre-labelled data does not cover all possible operating conditions, system states or image classes. It is also recommended for a refinement of the classifiers during the on-line mode in order to boost predictive performance with more loaded samples. We will present two types of on-line evolving image classifiers: The first one is a clustering-based classification approach, which exploits conventional vector quantization, forming an incremental evolving variant around it and extending it to the supervised classification case. The second one is an evolving fuzzy classifier approach which comes with two model architectures, classical single model and a novel multi-model architecture, the later exploiting indicator matrices/vectors for training. The approaches are evaluated in three different on-line surface inspection systems dealing with CD imprint inspection, egg inspection and inspection of metal rotor parts. The evaluation will show the impact of on-line evolved versus ‘static’ classifiers kept fixed during the whole on-line process.     

一种基于信息熵的多分类器动态组合方法

为提高数据分类的性能,提出了一种基于信息熵[1]的多分类器动态组合方法（EMDA）。此方法在多个UCI标准数据集上进行了测试,并与由集成学习算法—AdaBoost,训练出的各个基分类器的分类效果进行比较,证明了该算法的有效性。     

一种模糊分类器集成的方法

提出了一种基于模糊积分的模糊分类器集成的方法，该方法能在模糊分类器生成过程中，进一步减少主观因素的参与成份，使分类模器具有更好的稳定性和更高的分类识别率。给出了基于隶属度矩阵的模糊积分密度确定方法，介绍了基于模糊积分的分类器集成算法。用权威的数据集作为实验数据集，将提出方法与已有的分类器集成方法进行实验比较，评测了所提出方法的有效性。     

一种使用启发式搜索优化的模糊规则分类方法

文章提出了一种基于模糊规则的分类方法。该方法首先介绍了基于模糊C均值聚类的模糊规则提取,然后利用所建立的模糊规则库设计了一种分类算法,并且利用启发式搜索来精简分类规则。使用IRIS数据对该文的方法进行了性能测试,结果表明该方法在训练样本较少的情况下,能得到很好的分类效果,并且通过规则精简,所使用的规则数目大大下降,而分类性能更加优良。     

基于模糊分类关联规则的分类系统

为了构建高性能的分类系统，应用模糊集软化数量型属性的划分边界，提出了模糊分类关联规则的挖掘算法。由于模糊集能很好地贴近人类的思维方式，因此挖掘得到的模糊分类关联规则易于被人理解．接着提出了基于模糊分类关联规则的分类系统，并采用遗传优化算法训练分类系统．实例分析的结果表明，基于模糊分类关联规则的分类系统具有较好的精度和可解释性．     

基于海量样本的模糊分类系统的设计

使用支持向量机理论直接求海量数据的模糊分类系统是比较困难的。为了解决这个问题，该文提出了基于邻域原理计算支持向量，利用支持向量求出分类超平面，再设计模糊分类系统的方法。实验结果表明，该方法可以有效地解决对海量数据的模糊分类系统的设计 问题。