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1.
归纳逻辑程序设计(ILP)是机器学习的一个重要分支,给定一个样例集和相关背景知识,ILP研究如何构建与其相一致的逻辑程序,这些逻辑程序由有限一阶子句组成。文章描述了一种综合当前一些ILP方法多方面优势的算法ICCR,ICCR溶合了以FOIL为代表的自顶向下搜索策略和以GOLEM为代表的自底向上搜索策略,并能根据需要发明新谓词、学习递归逻辑程序,对比实验表明,对相同的样例及背景知识,ICCR比FOIL和GOLEM能学到精度更高的目标逻辑程序。  相似文献   

2.
语义网络数据挖掘是基于语义网络环境的数据挖掘,它给数据挖掘技术的应用研究提出了新的课题。归纳逻辑程序设计是由机器学习与逻辑程序设计交叉所形成的一个研究领域,它为知识工程等人工智能的应用领域提供了新的强有力的技术支持。分析了现有几种常用数据挖掘技术在语义Web环境下应用的局限性,提出了采用归纳逻辑程序设计(ILP)作为语义Web上适合的数据挖掘技术,给出了应用这种技术的算法描述,通过具体实例验证了其可行性。  相似文献   

3.
数字序列抗原内部存在许多语义特征,针对抗原进行语义识别可以提高系统检测的准确性。基于抗原的相对时序关系,该文采用了一阶逻辑作为抗原和淋巴细胞的基本描述语言,以扩展逻辑程序构造淋巴细胞的时间语义逻辑模型,给出了淋巴细胞的逻辑表示形式。基于逻辑程序的稳定模型语义学,用稳定模型语义计算作为新的淋巴细胞的匹配算法。借鉴遗传归纳逻辑程序GILP的基本思想,给出了新的淋巴细胞的演化算法。  相似文献   

4.
虽然对归纳逻辑程序的极限行为至今并没有深入的研究,但是通常在分析正在执行的增量式或在线归纳学习算法时,必须考虑这种程序的极限行为.某些归纳学习算法如果不考虑极限行为可能运行到最后会发生错误.如果给定一个递增的例子集合序列,一个归纳逻辑程序会产生一个相应的具有集合论极限的Horn逻辑程序序列,则此归纳逻辑程序是收敛的,并且如果该Horn逻辑程序序列关于例子集合序列的极限是极限正确的,则此归纳逻辑程序是极限正确的,还说明GOLEM系统不是极限正确的.为了解决这个问题,提出了一个极限正确的称为优先GOLEM系统的归纳逻辑系统,并证明了在一定的限制下,优先GOLEM系统的算法是极限正确的.  相似文献   

5.
针对目前归纳逻辑程序设计(inductive logic programming,ILP)系统要求训练数据充分且无法利用无标记数据的不足,提出了一种利用无标记数据学习一阶规则的算法——关系tri-training(relational-tri-training,R-tri-training)算法。该算法将基于命题逻辑表示的半监督学习算法tri-training的思想引入到基于一阶逻辑表示的ILP系统,在ILP框架下研究如何利用无标记样例信息辅助分类器训练。R-tri-training算法首先根据标记数据和背景知识初始化三个不同的ILP系统,然后迭代地用无标记样例对三个分类器进行精化,即如果两个分类器对一个无标记样例的标记结果一致,则在一定条件下该样例将被标记给另一个分类器作为新的训练样例。标准数据集上实验结果表明:R-tri-training能有效地利用无标记数据提高学习性能,且R-tri-training算法性能优于GILP(genetic inductive logic programming)、NFOIL、KFOIL和ALEPH。  相似文献   

6.
基于位串编码的遗传归纳逻辑程序设计   总被引:1,自引:1,他引:0       下载免费PDF全文
归纳逻辑程序设计是基于一阶逻辑的数据挖掘新方法。一阶规则挖掘是目标谓词和背景知识谓词对应的各种原子的复杂组合优化问题。该文根据Occam’s razor原理提出原子的位串编码,设计相应的遗传箅子,基于sequential covering策略提出采用遗传算法作为搜索策略的遗传归纳逻辑程序设计算法GILP。在连通图问题和gcd问题上验证算法的可行性。  相似文献   

7.
遗传归纳逻辑程序设计的个体编码生长现象   总被引:3,自引:0,他引:3  
遗传归纳逻辑程序设计(GILP)的个体编码生长现象严重影响了算法的性能和规则的可读性.通过对变长编码的模式分析,解释了GILP的个体编码生长现象.并发现,若从初始种群开始添加长度惩罚项来解决个体编码生长问题,种群会出现退化现象.而采取在演化的初期不添加惩罚项,在种群的性状有了明显改善后再添加惩罚的策略,既可避免种群退化,又可有效解决个体编码生长问题.  相似文献   

8.
刘曦  张潇璐  张学杰 《计算机应用》2016,36(8):2128-2133
资源分配策略的研究一直是云计算领域研究的热点和难点,针对异构云计算环境下多维资源的公平分配问题,结合基因算法(GA)和差分进化算法(DE),分别给出了两种兼顾分配公平性和效率的资源分配策略,改进了解矩阵表达式使异构云系统中的主资源公平分配(DRFH)模型转化成为整数线性规划(ILP)模型,并提出了基于最大任务数匹配值(MTM)的初始解产生机制和使不可行解转化为可行解的修正操作,以此提高算法的收敛速度,使其能够快速有效地得到最优分配方案。实验结果表明,基于GA和DE算法的多维资源公平分配策略可以得到近似最优解,在最大化最小主资源份额目标值和资源利用率方面明显优于Best-Fit DRFH和Distributed-DRFH,而且针对不同任务类型的资源需求,具有较强的自适应能力。  相似文献   

9.
基于粒距和动态区间的粒子群权值调整策略   总被引:3,自引:0,他引:3  
左旭坤  苏守宝 《计算机应用》2010,30(9):2286-2289
由于标准粒子群优化(PSO)算法把惯性权值作为全局参数,因此很难适应复杂的非线性优化过程。针对这一问题,提出了一种基于粒距和动态区间的权值调整策略(PSSIW),根据粒子的粒距大小在动态区间内选取不同的权值,并通过区间的动态变化来控制算法的收敛速度。设计了四种不同的动态区间,并采用三个常用的标准测试函数测试不同区间对算法性能的影响。通过与标准粒子群算法比较发现,该策略提高了算法摆脱局部极值的能力,是一种新型全局收敛粒子群算法。  相似文献   

10.
目前大多数数据挖掘方法是从单关系中发现模式,而多关系数据挖掘(MRDM)则可直接从关系数据库的多表中抽取有效模式。MRDM可以解决原有命题数据挖掘方法不能解决的问题,它不仅有更强的信息表示能力,可以表示和发现更复杂的模式,还可以在挖掘进程中有效地利用背景知识来提高挖掘效率和准确率。近年来,借鉴归纳逻辑程序设计(ILP)技术,已经形成许多多关系数据挖掘方法,如关系关联规则挖掘方法、关系分类聚类方法等。  相似文献   

11.
Inductive logic programming (ILP) algorithms are classification algorithms that construct classifiers represented as logic programs. ILP algorithms have a number of attractive features, notably the ability to make use of declarative background (user-supplied) knowledge. However, ILP algorithms deal poorly with large data sets (>104 examples) and their widespread use of the greedy set-covering algorithm renders them susceptible to local maxima in the space of logic programs.This paper presents a novel approach to address these problems based on combining the local search properties of an inductive logic programming algorithm with the global search properties of an evolutionary algorithm. The proposed algorithm may be viewed as an evolutionary wrapper around a population of ILP algorithms.The evolutionary wrapper approach is evaluated on two domains. The chess-endgame (KRK) problem is an artificial domain that is a widely used benchmark in inductive logic programming, and Part-of-Speech Tagging is a real-world problem from the field of Natural Language Processing. In the latter domain, data originates from excerpts of the Wall Street Journal. Results indicate that significant improvements in predictive accuracy can be achieved over a conventional ILP approach when data is plentiful and noisy.  相似文献   

12.
13.
《Artificial Intelligence》2007,171(16-17):939-950
In this paper we propose a new formalization of the inductive logic programming (ILP) problem for a better handling of exceptions. It is now encoded in first-order possibilistic logic. This allows us to handle exceptions by means of prioritized rules, thus taking lessons from non-monotonic reasoning. Indeed, in classical first-order logic, the exceptions of the rules that constitute a hypothesis accumulate and classifying an example in two different classes, even if one is the right one, is not correct. The possibilistic formalization provides a sound encoding of non-monotonic reasoning that copes with rules with exceptions and prevents an example to be classified in more than one class. The benefits of our approach with respect to the use of first-order decision lists are pointed out. The possibilistic logic view of ILP problem leads to an optimization problem at the algorithmic level. An algorithm based on simulated annealing that in one turn computes the set of rules together with their priority levels is proposed. The reported experiments show that the algorithm is competitive to standard ILP approaches on benchmark examples.  相似文献   

14.
Scaling Up Inductive Logic Programming by Learning from Interpretations   总被引:4,自引:0,他引:4  
When comparing inductive logic programming (ILP) and attribute-value learning techniques, there is a trade-off between expressive power and efficiency. Inductive logic programming techniques are typically more expressive but also less efficient. Therefore, the data sets handled by current inductive logic programming systems are small according to general standards within the data mining community. The main source of inefficiency lies in the assumption that several examples may be related to each other, so they cannot be handled independently.Within the learning from interpretations framework for inductive logic programming this assumption is unnecessary, which allows to scale up existing ILP algorithms. In this paper we explain this learning setting in the context of relational databases. We relate the setting to propositional data mining and to the classical ILP setting, and show that learning from interpretations corresponds to learning from multiple relations and thus extends the expressiveness of propositional learning, while maintaining its efficiency to a large extent (which is not the case in the classical ILP setting).As a case study, we present two alternative implementations of the ILP system TILDE (Top-down Induction of Logical DEcision trees): TILDEclassic, which loads all data in main memory, and TILDELDS, which loads the examples one by one. We experimentally compare the implementations, showing TILDELDS can handle large data sets (in the order of 100,000 examples or 100 MB) and indeed scales up linearly in the number of examples.  相似文献   

15.
归纳逻辑程序设计的核心问题是如何从背景知识中优选谓词构造满足约束的归纳假设,按Occam准则,满足约束的最精简归纳假设为优,但迄今归纳逻辑程序设计中精简归纳假设构造的计算复杂性尚未解决。  相似文献   

16.
Cropper  Andrew  Morel  Rolf 《Machine Learning》2021,110(4):801-856
Machine Learning - We describe an inductive logic programming (ILP) approach called learning from failures. In this approach, an ILP system (the learner) decomposes the learning problem into three...  相似文献   

17.
基于归纳逻辑程序设计的学习方法及其实现的研究   总被引:1,自引:0,他引:1  
归纳逻辑程序设计是机器学习领域中的一个新方法,它研究的是从实例和背景知识进行逻辑程序(新知识)的构造.本文介绍了归纳逻辑程序设计的基本理论和方法,并介绍了这种学习方法在专家系统中的应用情况.  相似文献   

18.
Cropper  Andrew  Tourret  Sophie 《Machine Learning》2020,109(7):1323-1369
Machine Learning - Many forms of inductive logic programming (ILP) use metarules, second-order Horn clauses, to define the structure of learnable programs and thus the hypothesis space. Deciding...  相似文献   

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