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1.
Genetic Programming and Evolvable Machines - Genetic Network Programming (GNP) is a relatively recently proposed evolutionary algorithm which is an extension of Genetic Programming (GP). However,...  相似文献   

2.
This paper introduces a new ensemble approach, Feature-Subspace Aggregating (Feating), which builds local models instead of global models. Feating is a generic ensemble approach that can enhance the predictive performance of both stable and unstable learners. In contrast, most existing ensemble approaches can improve the predictive performance of unstable learners only. Our analysis shows that the new approach reduces the execution time to generate a model in an ensemble through an increased level of localisation in Feating. Our empirical evaluation shows that Feating performs significantly better than Boosting, Random Subspace and Bagging in terms of predictive accuracy, when a stable learner SVM is used as the base learner. The speed up achieved by Feating makes feasible SVM ensembles that would otherwise be infeasible for large data sets. When SVM is the preferred base learner, we show that Feating SVM performs better than Boosting decision trees and Random Forests. We further demonstrate that Feating also substantially reduces the error of another stable learner, k-nearest neighbour, and an unstable learner, decision tree.  相似文献   

3.
Genetic Programming (GP) provides a novel way of classification with key features like transparency, flexibility and versatility. Presence of these properties makes GP a powerful tool for classifier evolution. However, GP suffers from code bloat, which is highly undesirable in case of classifier evolution. In this paper, we have proposed an operator named “DepthLimited crossover”. The proposed crossover does not let trees increase in complexity while maintaining diversity and efficient search during evolution. We have compared performance of traditional GP with DepthLimited crossover GP, on data classification problems and found that DepthLimited crossover technique provides compatible results without expanding the search space beyond initial limits. The proposed technique is found efficient in terms of classification accuracy, reduced complexity of population and simplicity of evolved classifiers.  相似文献   

4.
为了提高Boosting回归算法的稳定性,提出了动态加权的组合Boosting回归算法,即DA-Boosting算法。首先以BP神经网络作为弱学习器,再调用Boosting回归算法构造强学习器,最后以强学习器得到的回归函数作为子函数进行动态加权平均,得到最终的组合函数。几个经典的分析回归数据集的测试表明,该算法不但具有良好的泛化能力,而且泛化性能稳定。最后将DA-Boosting算法用于丙烯软测量建模,应用结果表明该软测量模型泛化性能好,测量精度高。  相似文献   

5.
一种新型GEP解码方法   总被引:1,自引:0,他引:1       下载免费PDF全文
基因表达式编程(Gene Expression Programming)是进化算法的最新成果。它继承了遗传算法(GA)编码简单与遗传程序设计(GP)有巨大空间搜索能力的优点。提出一种新的GEP解码方法:GEP的非物理树解码算法。其在不影响原算法其他性质的情况下极大地提高了传统解码算法的运行速度,在一定程度上解决了GEP进化过程中表达式树(Expression Tree,ET)建立和释放消耗巨大时空资源的瓶颈。  相似文献   

6.
Open issues in genetic programming   总被引:1,自引:0,他引:1  
It is approximately 50 years since the first computational experiments were conducted in what has become known today as the field of Genetic Programming (GP), twenty years since John Koza named and popularised the method, and ten years since the first issue appeared of the Genetic Programming & Evolvable Machines journal. In particular, during the past two decades there has been a significant range and volume of development in the theory and application of GP, and in recent years the field has become increasingly applied. There remain a number of significant open issues despite the successful application of GP to a number of challenging real-world problem domains and progress in the development of a theory explaining the behavior and dynamics of GP. These issues must be addressed for GP to realise its full potential and to become a trusted mainstream member of the computational problem solving toolkit. In this paper we outline some of the challenges and open issues that face researchers and practitioners of GP. We hope this overview will stimulate debate, focus the direction of future research to deepen our understanding of GP, and further the development of more powerful problem solving algorithms.  相似文献   

7.
Genetic programming (GP) extends traditional genetic algorithms to automatically induce computer programs. GP has been applied in a wide range of applications such as software re-engineering, electrical circuits synthesis, knowledge engineering, and data mining. One of the most important and challenging research areas in GP is the investigation of ways to successfully evolve recursive programs. A recursive program is one that calls itself either directly or indirectly through other programs. Because recursions lead to compact and general programs and provide a mechanism for reusing program code, they facilitate GP to solve larger and more complicated problems. Nevertheless, it is commonly agreed that the recursive program learning problem is very difficult for GP. In this paper, we propose techniques to tackle the difficulties in learning recursive programs. The techniques are incorporated into an adaptive Grammar Based Genetic Programming system (adaptive GBGP). A number of experiments have been performed to demonstrate that the system improves the effectiveness and efficiency in evolving recursive programs. Communicated by: William B. Langdon An erratum to this article is available at .  相似文献   

8.
In this paper, we propose novel recurrent architectures for Genetic Programming (GP) and Group Method of Data Handling (GMDH) to predict software reliability. The effectiveness of the models is compared with that of well-known machine learning techniques viz. Multiple Linear Regression (MLR), Multivariate Adaptive Regression Splines (MARS), Backpropagation Neural Network (BPNN), Counter Propagation Neural Network (CPNN), Dynamic Evolving Neuro-Fuzzy Inference System (DENFIS), TreeNet, GMDH and GP on three datasets taken from literature. Further, we extended our research by developing GP and GMDH based ensemble models to predict software reliability. In the ensemble models, we considered GP and GMDH as constituent models and chose GP, GMDH, BPNN and Average as arbitrators. The results obtained from our experiments indicate that the new recurrent architecture for GP and the ensemble based on GP outperformed all other techniques.  相似文献   

9.
针对多光谱图像分类这一多类别模式识别问题,将二进制纠错编码与GP(GeneticProgramming)算法相结合,并用改进后的编码矩阵代替原先的二进制编码矩阵对图像进行分类,从而建立了新的基于GP的多光谱图像分类算法,给出了用该方法对多光谱图像中地物进行分类的实例。结果表明与以往基于GP的分类方法相比,该文方法体现出较高的分类性能,为遗传规划在多类别模式识别问题中的应用提供了又一条可行的途径。  相似文献   

10.
Genetic Programming and Evolvable Machines - We introduce GPLS (Genetic Programming for Linear Systems) as a GP system that finds mathematical expressions defining an iteration matrix. Stationary...  相似文献   

11.
近年来恶意软件不断地发展变化,导致单一检测模型的准确率较低,使用集成学习组合多种模型可以提高检测效果,但集成模型中基学习器的准确性和多样性难以平衡。为此,提出一种基于遗传规划的集成模型生成方法,遗传规划可以将特征处理和构建集成模型两个阶段集成到单个程序树中,解决了传统恶意软件集成检测模型难以平衡个体准确率和多样性的问题。该方法以集成模型的恶意软件检出率作为种群进化依据,保证了基学习器的准确性;在构建集成模型时自动选择特征处理方法、分类算法和优化基学习器的超参数,通过输入属性扰动和算法参数扰动增加基学习器的多样性,根据优胜劣汰的思想进化生成具有高准确性和多样性的最优集成模型。在EMBER数据集上的结果表明,最优集成模型的检测准确率达到了98.88%;进一步的分析表明,该方法生成的模型具有较高的多样性和可解释性。  相似文献   

12.
高阶常微分方程的演化建模用于时间序列的分析   总被引:2,自引:1,他引:1  
本文提出采用高阶常微分方程模型代替传统的时序分析中所用的ARMA模型来实现一维动态系统的建模,并针对传统方法建模过程中所遇到的困难,设计了将遗传程序设计与遗传算法个嵌套的混合演化建模算法,以遗传程序设计优化模型结构,以遗传算法优化模型参数,首次成功地实现了动态系统的高阶微分方程建模过程自动化,对三个典型时间序列实例的实验结果表明:采用此算法可由计算机自动发现适合描述该动态系统的高阶常微分方程模型,  相似文献   

13.
摄像机标定是精密视觉测量的基础,传统的标定方法具有很多的缺陷。提出了一种新的双目视觉摄像机标定方法,通过引入基因表达式程序设计算法,挖掘其中潜在的坐标函数关系。将GEP标定方法与同类方案进行了比较,实验结果表明:新算法有效地提高了标定精度,加快了运算时间,具有较高的实用价值。  相似文献   

14.
Evolutionary algorithms are generally used to find or generate the best individuals in a population. Whenever these algorithms are applied to agent systems, they will lead to optimal solutions. Genetic Network Programming (GNP), which contains graph networks, is one of the developed evolutionary algorithms. When the aim is to forecast the share price or return, ascending and descending trends, volatilities, recent returns, fundamental and technical factors have remarkable impacts on the prediction. This is why technical indicators are used to constitute a set of trading rules. In this paper, we apply an integrated framework consisting of GNP model along with a reinforcement learning and Multi-Layer Perceptron (MLP) neural network to classify data and also time series models to forecast the stock return. Moreover, we utilize rules of accumulation based on the GNP model’s results to forecast the return. The aim of using these models alongside one another is to estimate one-day return. The results derived from 9 stocks with regard to the Tehran Stock Exchange Market. GNP extracts a prodigious number of rules on the basis of 5 technical indicators with 3 times period. Next, MLP network classifies data and finds the similarity between future data and past data concerning a stock (5 sub-period) through classification. Subsequently, a number of conditions are established, in order to choose the best estimation between GNP-RL and ARMA. Distinct comparison with the ARMA–GARCH model, which is operated for return estimation and risk measurement in many researches, demonstrates an extended forecasting power of the proposed model, by the name of GNP–ARMA, reducing error by a mean of 16%.  相似文献   

15.
一种基于多目标优化的遗传规划模型   总被引:1,自引:0,他引:1  
遗传规划常因进化过程中层次树的复杂度无节制的增大,导致运行时间过长而难以直接在工程上应用.本文在传统遗传规划中引入多目标优化原理,这种基于多目标优化的遗传规划模型不仅产生精度更高的最优结果,而且提供了一种在随机搜索过程中有效控制树结构长度的方法.通过对符号回归问题的实验验证,得到了较好的结果.  相似文献   

16.
The Body-Centered Cubic (BCC) and Face-Centered Cubic (FCC) lattices have been analytically shown to be more efficient sampling lattices than the traditional Cartesian Cubic (CC) lattice, but there has been no estimate of their visual comparability. Two perceptual studies (each with N = 12 participants) compared the visual quality of images rendered from BCC and FCC lattices to images rendered from the CC lattice. Images were generated from two signals: the commonly used Marschner-Lobb synthetic function and a computed tomography scan of a fish tail. Observers found that BCC and FCC could produce images of comparable visual quality to CC, using 30-35 percent fewer samples. For the images used in our studies, the L(2) error metric shows high correlation with the judgement of human observers. Using the L(2) metric as a proxy, the results of the experiments appear to extend across a wide range of images and parameter choices.  相似文献   

17.
We propose a sequential test procedure for transient detections in a stochastic process which can be expressed as an autoregressive moving average (ARMA) model. Preliminary analysis shows that if an ARMA(p,q) time series exhibits a transient behavior, then its residuals behave as an ARMA(Q,Q) process, where Qp + q. Based on this fact, we derive a new sequential test to determine when a transient behavior occurs in a given ARMA time series. Simulation experiments conducted in this study show that the proposed test can detect the occurrence of a transient in the ARMA model. We also apply the proposed method to detect transient changes in the pH of an erythromycin salt.  相似文献   

18.
混合GP-GA用于信息系统建模预测的研究   总被引:10,自引:1,他引:10  
该文克服了传统建模方法在模型选取及参数估计方面的困难与不足,提出了利用改进的遗传程序设计和改进的遗传算法相结合的混合GP-GA算法。一方面,遗传程序设计中加入了简约压力项,控制了代码过度增长,实现了不加先验知识的简洁非线性模型的自动获取。另一方面,遗传算法采用Gray编码,随机整群抽样选择,以优化模型中的参数,这在一定程度上补偿了遗传程序设计在演化过程中具有较好结构的模型可能因为其中的参数未能达到最优而被淘汰的损失。仿真实例和实际应用均表明混合GP-GA算法优于普通的回归分析及单纯的遗传程序设计方法,提高了拟合和预测精度,并且更适合反映问题的实际情况。  相似文献   

19.
为提高不平衡数据的分类性能,提出了基于度量指标优化的不平衡数据Boosting算法。该算法结合不平衡数据分类性能度量标准和Boosting算法,使用不平衡数据分类性能度量指标代替原有误分率指标,分别采用带有权重的正类和负类召回率、F-measure和G-means指标对Boosting算法进行优化,按照不同的度量指标计算Alpha 值进行迭代,得到带有加权值的弱学习器组合,最后使用Boosting算法进行优化。经过实验验证,与带有权重的Boosting算法进行比较,该算法对一定数据集的AUC分类性能指标有一定提高,错误率有所下降,对F-measure和G-mean性能指标有一定的改善,说明该算法侧重提高正类分类性能,改善不平衡数据的整体分类性能。  相似文献   

20.
针对一个需要Agent之间相互协作的多Agent角色分配问题,研究采取了一种GNP的模型结构来解决。GNP是GP的改进,GP是树型结构,而GNP是网络结构。文中首先分别描述了GP与GNP的模型结构和对应算法,然后通过使用负载传输问题来对比分析GNP与GP的性能,并通过计算机仿真负载传输问题中的基于能力的Agent角色分配问题类型,证实了GNP的有效性。  相似文献   

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