共查询到20条相似文献,搜索用时 0 毫秒
1.
2.
An incremental algorithm generating satisfactory decision rules and a rule post-processing technique are presented. The rule induction algorithm is based on the Apriori algorithm. It is extended to handle preference-ordered domains of attributes (called criteria) within Variable Consistency Dominance-based Rough Set Approach. It deals, moreover, with the problem of missing values in the data set. The algorithm has been designed for medical applications which require: (i) a careful selection of the set of decision rules representing medical experience and (ii) an easy update of these decision rules because of data set evolving in time, and (iii) not only a high predictive capacity of the set of decision rules but also a thorough explanation of a proposed decision. To satisfy all these requirements, we propose an incremental algorithm for induction of a satisfactory set of decision rules and a post-processing technique on the generated set of rules. Userʼns preferences with respect to attributes are also taken into account. A measure of the quality of a decision rule is proposed. It is used to select the most interesting representatives in the final set of rules. 相似文献
3.
4.
5.
基于Rough Set带结论域的关联规则挖掘 总被引:2,自引:0,他引:2
论文构建了一种基于RoughSet(RS)带结论域的强关联规则挖掘模型,采用约简决策表和改进的Apriori算法来挖掘关联规则,提高了关联规则的挖掘效率和挖掘质量,提出并实现了带结论域的关联规则挖掘的解决方案。 相似文献
6.
7.
运用粗糙集和遗传算法的理论,为大型的数据挖掘提供了一种新的方法。首先通过粗糙集理论对数据进行预处理,然后对属性简约,最后通过遗传算法进行规则提取,寻找最优解。 相似文献
8.
9.
粗集作为一种数据分析方法,能有效地从不精确的、不完整的数据中发现知识。决策支持系统涉及到对不确定因素和对不完备信息的处理。应用粗集理论可以在决策支持系统中对不完备数据进行分析、推理,提取有用特征,简化信息处理,得出肯定结论。 相似文献
10.
11.
文章提出在多层分类器中使用粗集理论来进行网络的设计,由于粗集理论有强大的数值分析能力,而多层分类器具有准确的逼近收敛能力和较高的精度,所以通过两者的结合,可以得到一种可理解性好、计算简单、收敛速度快的新型多层分类器模型。首先利用粗集理论来提取原始的领域知识,然后通过计算决策表的相对约简来产生规则,这些规则的依赖性因子被设为多层分类器的初始连接权值,这些权值在训练学习中得到改进。文章最后给出了一个决策表的实例来进一步验证了该方法的高效性和正确性。 相似文献
12.
13.
基于Rough Set的最简决策树确定算法的研究 总被引:6,自引:2,他引:6
朱红 《计算机工程与应用》2003,39(13):129-131
决策树是一种有效用于分类的数据采掘方法,有确定性和非确定性决策树。传统的方法是通过信息熵的计算去生成决策树,计算量大。目前有人用RS方法去计算信息熵,但存在局限性。该文将指出其局限性,并给出了一种有效的属性选择算法,确定了最简确定性和非确定性决策树的判别准则及其通用生成算法。 相似文献
14.
15.
16.
17.
《国际计算机数学杂志》2012,89(7):789-796
Rough set theory (RS), introduced by Zdzislaw Pawlak in the early 1980s, is a methodology that concerned with the classificatory analysis of imprecise, uncertain or incomplete information or knowledge expressed in terms of data acquired from experiences or observations. It has the ability to distinguish between object and reason about the objects in the universe in which objects are perceived through the information that is available about them through the values for a predetermined set of attribute. The main advantage of RS is that it requires no additional information to the data represented in table. On the other hand, Supervised Neural Network learns by abstracting a mapping function from the training data for classification purposes. However the drawback of using a supervised neural network is that a large amount of training data must be provided for it to obtain an accurate mapping function. The problem is further aggravated if the data are in the continuous form (real values). Thus, in this paper we overcome the problem by transforming the training data in the continuous form into discrete values using Rough Sets theory and Boolean Reasoning technique. Here, global shape features are chosen to represent the logo images. The invariant features representing logo images are obtained by using the Geometric Invariant Moment Technique (Hu, 1962). The classification results prove that discretization using Rough Sets and Boolean Reasoning can reduce the training cycle and significantly increase the accuracy of the classification of logo images. 相似文献
18.
19.
一种基于关联规则挖掘的粗糙集约简算法 总被引:6,自引:1,他引:6
针对粗糙集理论中的约简这个重要问题进行了研究,引入关联规则挖掘中的支持度和置信度概念,提出一种基于关联规则挖掘算法思想的约简算法,从而得到更有效的约简。 相似文献