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1.
Tabu搜索在特征选择中的应用   总被引:25,自引:0,他引:25  
研究利用Tabu搜索从大特征集中选择一组有效特征的问题.分析了Tabu搜索中 表长、邻域大小和候选解数量等参数对Tabu搜索的影响.对两种特征选择的问题,与经典及 最近新提出的一些特征选择方法如SFS,SBS,GSFS,GSBS,PTA,BB,GA和SFFS,SFBS等 算法的实验比较表明,Tabu搜索在求解时间和解的质量上都取得了满意的结果.  相似文献   

2.
针对网络流量特征属性的优化选择问题,提出了一种结合粗糙集和禁忌搜索的网络流量特征选择方法(RS-TS).该方法通过粗糙集算法对网络流量特征属性进行约简,将所得到的特征子集作为禁忌搜索的初始解,并利用禁忌搜索得到最优特征子集.实验验证RS-TS方法优于基于GA的特征选择方法和基于IG的特征选择方法,能够有效地去除网络流量的冗余特征属性,提高网络流量分类精度.  相似文献   

3.
一种高效的面向轻量级入侵检测系统的特征选择算法   总被引:9,自引:0,他引:9  
陈友  沈华伟  李洋  程学旗 《计算机学报》2007,30(8):1398-1408
特征选择是网络安全、模式识别、数据挖掘等领域的重要问题之一.针对高维数据对象,特征选择一方面可以提高分类精度和效率,另一方面可以找出富含信息的特征子集.文中提出一种wrapper型的特征选择算法来构建轻量级入侵检测系统.该算法采用遗传算法和禁忌搜索相混合的搜索策略对特征子集空间进行随机搜索,然后利用提供的数据在无约束优化线性支持向量机上的平均分类正确率作为特征子集的评价标准来获取最优特征子集.文中按照DOS,PROBE,R2L,U2R 4个类别对KDD1999数据集进行分类,并且在每一类上进行了大量的实验.实验结果表明,对每一类攻击文中提出的特征选择算法不仅可以加快特征选择的速度,而且基于该算法构建的入侵检测系统在建模时间、检测时间、检测已知攻击、检测未知攻击上,与没有运用特征选择的入侵检测系统相比具有更好的性能.  相似文献   

4.
5.
Searching for an optimal feature subset from a high-dimensional feature space is an NP-complete problem; hence, traditional optimization algorithms are inefficient when solving large-scale feature selection problems. Therefore, meta-heuristic algorithms are extensively adopted to solve such problems efficiently. This study proposes a regression-based particle swarm optimization for feature selection problem. The proposed algorithm can increase population diversity and avoid local optimal trapping by improving the jump ability of flying particles. The data sets collected from UCI machine learning databases are used to evaluate the effectiveness of the proposed approach. Classification accuracy is used as a criterion to evaluate classifier performance. Results show that our proposed approach outperforms both genetic algorithms and sequential search algorithms.  相似文献   

6.
针对基于肌电(EMG)信号的情感识别问题,提出了一种新颖的特征选择方法.该方法用相关性分析对原始特征降维,再利用改进的禁忌搜索算法结合Fisher分类器,对高兴、厌恶、悲伤、惊奇、愤怒和恐惧6种肌电信号的情感进行特征选择.实验结果表明,该方法能以较少的特征获得较高的识别率,得到了有利于情感识别系统建立的有效特征子集.  相似文献   

7.
Many applications — such as content-based image retrieval, subspace clustering, and feature selection — may benefit from efficient subspace similarity search. Given a query object, the goal of subspace similarity search is to retrieve the most similar objects from the database, where the similarity distance is defined over an arbitrary subset of dimensions (or features) — that is, an arbitrary axis-aligned projective subspace — specified along with the query. Though much effort has been spent on similarity search in fixed subspaces, relatively little attention has been given to the problem of similarity search when the dimensions are specified at query time. In this paper, we propose new methods for the subspace similarity search problem for real-valued data. Extensive experiments are provided showing very competitive performance relative to state-of-the-art solutions.  相似文献   

8.
一种新的应用于文本特征子集优化的GATS算法   总被引:1,自引:0,他引:1       下载免费PDF全文
针对文本分类中特征子集优化问题,将禁忌搜索算法引入到遗传算法中对遗传算法的核心算子——交叉算子进行改进形成禁忌交叉算子,改进后的算法称为GATS(遗传禁忌搜索算法),并将其应用在文本分类中来实现空间降维。实验证明,应用此方法进行文本特征项的选取不仅能够保持GA和TS算法本身的优点,还能在一定程度上提高文本分类的准确率。  相似文献   

9.
翟俊海    刘博  张素芳 《智能系统学报》2017,12(3):397-404
特征选择是指从初始特征全集中,依据既定规则筛选出特征子集的过程,是数据挖掘的重要预处理步骤。通过剔除冗余属性,以达到降低算法复杂度和提高算法性能的目的。针对离散值特征选择问题,提出了一种将粗糙集相对分类信息熵和粒子群算法相结合的特征选择方法,依托粒子群算法,以相对分类信息熵作为适应度函数,并与其他基于进化算法的特征选择方法进行了实验比较,实验结果表明本文提出的方法具有一定的优势。  相似文献   

10.
Rough set theory has been proven to be an effective tool to feature subset selection. Current research usually employ hill-climbing as search strategy to select feature subset. However, they are inadequate to find the optimal feature subset since no heuristic can guarantee optimality. Due to this, many researchers study stochastic methods. Since previous works of combination of genetic algorithm and rough set theory do not show competitive performance compared with some other stochastic methods, we propose a hybrid genetic algorithm for feature subset selection in this paper, called HGARSTAR. Different from previous works, HGARSTAR embeds a novel local search operation based on rough set theory to fine-tune the search. This aims to enhance GA’s intensification ability. Moreover, all candidates (i.e. feature subsets) generated in evolutionary process are enforced to include core features to accelerate convergence. To verify the proposed algorithm, experiments are performed on some standard UCI datasets. Experimental results demonstrate the efficiency of our algorithm.  相似文献   

11.
特征选择技术是机器学习和数据挖掘任务的关键预处理技术。传统贪婪式特征选择方法仅考虑本轮最佳特征,从而导致获取的特征子集仅为局部最优,无法获得最优或者近似最优的特征集合。进化搜索方式则有效地对特征空间进行搜索,然而不同的进化算法在搜索过程中存在自身的局限。本文吸取遗传算法(GA)和粒子群优化算法(PSO)的进化优势,以信息熵度量为评价,通过协同演化的方式获取最终特征子集。并提出适用于特征选择问题特有的比特率交叉算子和信息交换策略。实验结果显示,遗传算法和粒子群协同进化(GA-PSO)在进化搜索特征子集的能力和具体分类学习任务上都优于单独的演化搜索方式。进化搜索提供的组合判断能力优于贪婪式特征选择方法。  相似文献   

12.
We address the feature subset selection problem for classification tasks. We examine the performance of two hybrid strategies that directly search on a ranked list of features and compare them with two widely used algorithms, the fast correlation based filter (FCBF) and sequential forward selection (SFS). The proposed hybrid approaches provide the possibility of efficiently applying any subset evaluator, with a wrapper model included, to large and high-dimensional domains. The experiments performed show that our two strategies are competitive and can select a small subset of features without degrading the classification error or the advantages of the strategies under study.  相似文献   

13.
一种求解车间作业调度的自适应混合遗传算法   总被引:2,自引:0,他引:2  
针对遗传算法和禁忌搜索算法在求解车间作业调度问题存在的全局收敛性差、种群早熟化、收敛速度慢等缺陷,提出了一种自适应遗传禁忌搜索算法。算法通过自适应调整遗传算子中的变异概率,改善了遗传算法的收敛速度;通过增加禁忌表来选择杂交产生的个体,避免迂回搜索,以禁忌搜索算法作为变异算子,增加种群的多样性,避免算法陷入局部最优。通过仿真实例,验证了算法的收敛性和抗局部收敛性。  相似文献   

14.
唐小川  邱曦伟  罗亮 《计算机应用》2018,38(7):1857-1861
针对文本分类中的特征选择问题,提出了一种考虑特征之间交互作用的文本分类特征选择算法——Max-Interaction。首先,通过联合互信息(JMI),建立基于信息论的文本分类特征选择模型;其次,放松现有特征选择算法的假设条件,将特征选择问题转化为交互作用优化问题;再次,通过最大最小法避免过高估计高阶交互作用;最后,提出一个基于前向搜索和高阶交互作用的文本分类特征选择算法。实验结果表明,Max-Interaction比交互作用权重特征选择(IWFS)的平均分类精度提升了5.5%,Max-Interaction比卡方统计法(Chi-square)的平均分类精度提升了6%,Max-Interaction在93%的实验中分类精度高于对比方法,因此,Max-Interaction能有效利用交互作用提升文本分类特征选择的性能。  相似文献   

15.
王欢  张丽萍  闫盛  刘东升 《计算机应用》2017,37(4):1135-1142
为解决克隆代码有害性预测过程中特征无关与特征冗余的问题,提出一种基于相关程度和影响程度的克隆代码有害性特征选择组合模型。首先,利用信息增益率对特征数据进行相关性的初步排序;然后,保留相关性排名较高的特征并去除其他无关特征,减小特征的搜索空间;接着,采用基于朴素贝叶斯等六种分类器分别与封装型序列浮动前向选择算法结合来确定最优特征子集。最后对不同的特征选择方法进行对比分析,将各种方法在不同选择准则上的优势加以利用,对特征数据进行分析、筛选和优化。实验结果表明,与未进行特征选择之前对比发现有害性预测准确率提高15.2~34个百分点以上;与其他特征选择方法比较,该方法在F1测度上提高1.1~10.1个百分点,在AUC指标上提升达到0.7~22.1个百分点,能极大地提高有害性预测模型的准确度。  相似文献   

16.
Rough set theory is one of the effective methods to feature selection, which can preserve the meaning of the features. The essence of rough set approach to feature selection is to find a subset of the original features. Since finding a minimal subset of the features is a NP-hard problem, it is necessary to investigate effective and efficient heuristic algorithms. Ant colony optimization (ACO) has been successfully applied to many difficult combinatorial problems like quadratic assignment, traveling salesman, scheduling, etc. It is particularly attractive for feature selection since there is no heuristic information that can guide search to the optimal minimal subset every time. However, ants can discover the best feature combinations as they traverse the graph. In this paper, we propose a new rough set approach to feature selection based on ACO, which adopts mutual information based feature significance as heuristic information. A novel feature selection algorithm is also given. Jensen and Shen proposed a ACO-based feature selection approach which starts from a random feature. Our approach starts from the feature core, which changes the complete graph to a smaller one. To verify the efficiency of our algorithm, experiments are carried out on some standard UCI datasets. The results demonstrate that our algorithm can provide efficient solution to find a minimal subset of the features.  相似文献   

17.
This paper presents a new approach to the selection of prototypes for the nearest neighbor rule which aims at obtaining an optimal or close-to-optimal solution. The problem is stated as a constrained optimization problem using the concept of consistency. In this context, the proposed method uses tabu search in the space of all possible subsets. Comparative experiments have been carried out using both synthetic and real data in which the algorithm has demonstrated its superiority over alternative approaches. The results obtained suggest that the tabu search condensing algorithm offers a very good tradeoff between computational burden and the optimality of the prototypes selected.  相似文献   

18.
一种用于特征选择的禁忌搜索算法   总被引:1,自引:1,他引:0  
特征选择问题是机器学习和模式识别中的一个重要问题,特征的优劣直接影响分类器的设计和性能。首先介绍了禁忌搜索的基本原理,然后将禁忌搜索方法用于特征选择,并给出了新算法的实现方法及步骤。仿真实验表明,该方法在求解的效率和解的质量方面都达到了令人满意的效果。  相似文献   

19.
通过遗传算法进行系统级软硬件划分   总被引:4,自引:3,他引:4  
介绍采用遗传算法解决软硬件划分问题,具体讨论在遗传算法实现过程中的编码和解码,适应值函数的选取,选择,交叉,变异算子的实现、收敛准则的决定等问题的处理,与已发表文献的处理方法进行比较,最后通过随机实验取得好的结果。  相似文献   

20.
This study considers production planning problems involving multiple products, multiple resources, multiple periods, setup times, and setup costs. It can be formulated as a mixed integer program (MIP). Solving a realistic MIP production planning problem is NP-hard; therefore, we use tabu search methods to solve such a difficult problem. Furthermore, we improve tabu search by a new candidate list strategy, which sorts the neighbor solutions using post-optimization information provided by the final tableau of the linear programming simplex algorithm. A neighbor solution with higher priority in the ranking sequence has a higher probability of being the best neighbor solution of a current solution. According to our experiments, the proposed candidate list strategy tabu search produces a good solution faster than the traditional simple tabu search. This study also suggests that if the evaluation of the entire neighborhood space in a tabu search algorithm takes too much computation and if an efficient and effective heuristic to rank the neighbor solutions can be developed, the speed of tabu search algorithm could be significantly increased by using the proposed candidate list strategy.  相似文献   

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