南京大学学报(自然科学版) ›› 2013, Vol. 49 ›› Issue (2): 250–257.

• • 上一篇    下一篇

 多标记粒度不完备信息系统的粗糙近似*

 顾沈明**,叶晓敏,吴伟志
  

  • 出版日期:2015-10-22 发布日期:2015-10-22
  • 作者简介: (浙江海洋学院数理与信息学院,舟山 316000)
  • 基金资助:
    国家自然科学基金(61272021,61075120,11071284,61173181),浙江省自然科学基金(LZ12F03002),浙江省科技厅优先主题重大项日(2008C13068)

 Rough set approximations in incomplete information systems
with multrlabeled granules

 Gu Shen-Ming ,Ye Xiao-Min ,Wu Wei - Zhi   

  • Online:2015-10-22 Published:2015-10-22
  • About author:(School of Mathematics,Physics and information Science,Zhejiang Ocean University,Zhoushan,316000,China)

摘要: 在粒计算看来,一个粒是由多个比较小的颗粒组成更大的一个单元.在许多场合下,由于不同
尺度对数据集分割而得到不同层次的信息粒度,这些不同的信息粒度可以用不同的标记块来区分.首先
介绍了用一个满射来定义标记块的概念,接着在标记块的基础上给出了多标记粒度结构.针对多标记粒
度结构,先给出了完备信息系统中粒度信息变换函数,接着在多标记不完备信息系统中重新定义了粒度
信息变换函数.由粒度信息变换函数,可以在多标记不完备信息系统中得到信息粒度的一个层次结构.
在每一个层次中,利用非对称相似关系定义相似类,进而定义集合的上近似、下近似、近似精度和粗糙度
等概念.在不同层次之间,分别讨论了上近似、下近似、近似精度和粗糙度的性质,在不同的知识粒度下
探索的知识近似的变化规律.

Abstract: The key to granular computing is to make use of granules in problem solving. With the view point of
granular computing,the notion of a granule may be interpreted as one of the numerous small particles forming a lai-
ger unit.ln many situations, there arc different granules at different levels of scale in data sets having hierarchical
scale structures.The different granules can be described by different labeled blocks.The concept of labeled blocks de-
termined by a surjective function is first introduced in this paper. Based on the labeled blocks,the multi-labeled gran-
ular structure is also introduced.Then, the function of granular information transformation is proposed in multi-la-
bcled complete information systems. Duc to the rampant existence of incomplete information systems in practice, a
new approach for granular knowledge acquisition in incomplete information system became necessity.Therefore,a
new function of granular information transformation is defined in multi-labeled incomplete information systems. With
the function of granular information transformation,a hierarchical structure of granules can be obtained in multi-la-
beled incomplete information system. At every level,the similarity class can be defined by using asymmetric similarity
relation,and the lower and upper approximations of any subset of  universe in multi-labeled incomplete information
systems can be defined based on similarity class. Analogously,accuracy of approximations and roughness are also de-
fined as usual at one level. Furthermore, the properties of lower approximations, upper approximations, accuracy of
approximations and roughness between different levels arc discussed respectivcly,and some examples arc also illus-
trativcd.Those properties may be useful to find laws of knowledge variation in multi-labeled incomplete information
system while the granular sizc changing.

[1]Wu W Z,Leung Y.Theory and applications of grams lar labeled partitions in multi-scale decision tables. In
formation Sciences,2011,181:3878一3897.
[2]Zadeh L A. Fuzzy sets and information granularity.Gupta N,Ragade R, Yager R R. Advances in Fuzzy
Set Theory and Applications. North-Holland, Am sterdam, 1979,3一18.
[3]Zadeh L A. Towards a theory of fuzzy information granulation and its centrality in human reasoning and
fuzzy logic. Fuzzy Sets and Systems, 1997,90:111 ~127.
[4]Bargiela A, Pedrycz W. Granular computing; An in troduction. Boston; Kluwer Academic Publishers 2002,1一455.
[5]Bargicla A,Pedrycz W. Toward a theory of granular computing for human-centered information proce-ss
ing. IEEE Transactions on Fuzzy Systems,2008,16: 320一330.
[6]Hu Q H,Liu J F, Yu D R. Mixed feature selection based on granulation and approximation. Knowledge
Based Systems,2008,21;294一304.
[7]Qian Y H,Liang J Y, Dang C Y. Knowledge strur ture,knowledge granulation and knowledge distance
in a knowledge base. international Journal of Ap- proximate Reasoning,2009,50:174一188.
[8]Inuiguchi M,Hirano S,Tsumoto S. Rough set theory and granular computing. Heidelberg; Springer,2002,315.
[9]LinT Y,Yao Y Y,Zadeh L A. Data mining, rough sets and granular computing. Physica-Ver- lag, Heidelberg, 2002,1一541.
[10]Yao Y Y. Stratified rough sets and granular com- puting. Dave R N,Sudkamp T.The 18th Interna-
tional Conference of the North American Fuzzy information Processing Society. New York:IEEE Press.1999.800一804.
[11]Yao Y Y, Information granulation and rough set approximation, International Journal of Intelligent Systems, 2001,16:87一104.
[12]Yao Y Y,Liau C J,Zhong N. Granular computing based on rough sets, quotient space theory,and
belief functions, Zhong N. Foundations of Intelli- gent Systems,LNAI,Heidelberg; Springer, 2003,2871:152一159.
[13]Pawlak Z. Rough sets,International Journal of Computer and Information Science, 1982,11(5) :341一356.
[14]Pawlak Z. Rough sets;Theoretical aspects of rea soning about data. Boston; Kluwer Academic Publishers, 1991,1一229.
[15]Liu X Y,Wu J X,Zhou G Z. A method about based on the model cascade type imbalanced data
classification. Journal of Nanjing Univcrsity(Nat- ural Sciences),2006,42(2):148一1 55.(刘青影,
吴建鑫,周志华.一种基于级联模型的类别不平衡数据分类方法.南京大学学报(自然科学),2006, 42(2):148一155).
[16]Wang L,Qi u T R,He N,et al. A method for fea- ture selection based on rough sets and ant colony
optimization algorithm. Journal of Nanjing Uni- versity( Natural Sciences),2010,46(5):487一
493.(王 璐,邱桃荣,何妞等.基于粗糙集和蚁群优化算法的特征选择方法.南京大学学报(自然科学),2010,46(5):487-493).
[17]Yao Y Y. A partition model of granular compu- ting.Transactions on rough sets I,
LNCS, Heidel-berg;Springer,2004,3100:232一253.
[18]Zhang W X, Wu W Z, Liang J Y, et al. Rough set theory and method. Beijing; Science Publishing,
2001 ,15-90.(张文修,吴伟志,梁吉业等.粗糙集理论与方法.北京:科学出版社,2001,15-90).
[19]Zhang W X,Mi J S,Wu W Z. Knowledge reductions in inconsistent information systems. Chinese Journal
of Compuers, 2003 , 26 ( 1) ; 12 - 18.(张文修,米据生,吴伟志.不协调目标信息系统的知识约简.计算机学报,2003 26(1):12 -18 ).
[20]Yi X H,Wang G Y, Hu F. A new dynamic sample recognition algorithm based on rough set. Journal of
Nanj ing University ( Natural Sciences) , 2010 , 46 ( 5 ): 501-506.易兴辉,土国lg},胡峰.一种新的基
于粗糙集的动态样木识别算法.南京大学学报(自然科学),2010,46(5):501-506).
[21]Hu J , Wang G Y. Hierarchical model of covering granular space. Journal of Nanjing University
(Natural Sciences),2008,44(5):551一558.(胡军,王国胤.覆盖粒度空间的层次模型.南京大学学报(自然科学),2008,44(5):551-558).
[22]Chen Y M, Wu K S, Sun J H. Minimal attribute re- duction based on power set tree in decision table.
Journal of Nanjing University(Natural Sciences),2012,48(2);164-171.(陈玉明,吴克寿,孙金华.
基于幂树的决策表最小属性约简.南京大学学报(自然科学),2012,48(2);164-171).
[23]Gu S M, Wu W Z, Zheng Y. Rule acquisition in consistent multi-scale decision systems. The 8th
international conference on Fuzzy System and Knowledge Discovery, IEEE Computer Society, Los Alamitos,2011,390一393.
[24]Gu S M, Wu W Z. Knowledge acquisition in in- consistent multi-scale decision systems. The 6th
international Conference on Rough set and Knowledge Technology, LNAI,Hcidclbcrg; Springcr,2011,6954:669一678 .
[25]Stcfanowski J,Tsoukias A, Incomplete information tables and rough classification. Computational lntelli-
gence,2001,17:545一566.

No related articles found!
Viewed
Full text


Abstract

Cited

  Shared   
  Discussed   
No Suggested Reading articles found!