Birch algorithm . density-based method : if the density of neighborhood, that is the number of data objects, exceeds a certain value, the clustering process will be continued 基于密度的方法的主要思想是:只要邻近区域的密度(对象或数据点的数目)超过某个阈值,就继续聚类。
Dissimilarities are assessed base on the attribute values describing the objects . clustering processes are always carried out in the condition without pre-known knowledge, so the main task is to solve that how to get the clustering result in this premise 聚类分析依据的原则是使同一聚簇中的对象具有尽可能大的相似性,而不同聚簇中的对象具有尽可能大的相异性,聚类分析主要解决的问题是如何在没有先验知识的前提下,实现满足这种要求的聚簇的聚合。
However, there have still some unresolved problems : first, how to determine the number and size of the clusters automatically during the clustering process . second, how to utilize the " local " ridge regression method which including multiple regularization parameters in learning rbf network . third, those clusters in irregular form ca n't represented by radial basis function, thus we must find some other basis functions that can describe the irregular form 但是仍然存在几个问题尚待解决:首先,聚类时怎样自动确定簇的个数和半径;其次,如何利用含有多个正规化参数的局部岭回归方法进行rbf网络学习;第三,如果簇的形状是不规则的,则它很难用径向基函数来描述,因此需要研究其它能代表不规则形状的簇的基函数。
Clustering analysis is the method which partition class to the clustered objects as required of thing's characteristics . clustering processes are always carried out in the condition with no pre-known knowledge, so the most research task is to solve that how to get the clustering result in this premises 聚类分析是在没有先验知识支持的前提下,根据事物本身的特性研究被聚类对象的类别划分,实现满足这种要求的类的聚合,它所依据的原则是使同一类中的对象具有尽可能大的相似性,而不同类中的对象具有尽可能大的差异性。
clustering processes are always carried out in the condition with no pre-known knowledge, so the most research task is to solve that how to get the clustering result in th is premise . as the development of data mining, a number of clustering algorithms has been founded, in general, major clustering methods, can be classified into the following categories : partitioning methods; hierarchical methods; density-based methods; grid-based methods; model-methods; besides these, some clustering algorithms integrate the ideas of several clustering methods 正是由于聚类分析的重要性和特殊性,近年来在该领域的研究取得了长足的发展,涌现出了许多聚类分析的方法,如划分聚类方法(partitioningmethod)、层次聚类方法(hierarchicalmethod)、基于密度(density?based)的聚类方法、基于网格(grid?based)的聚类方法、基于模型(model?based)的聚类方法等等。
And it adds a-priori information into the patterns to change the method as a semi-supervised clustering . in the clustering process, the unlabelled patterns compare similarities with the labeled patterns, and then the accuracy of the algorithm can be increased . ( 3 ) the paper proposes an interactive learning-based image mining in remote sensing 由于遥感图像各类别在特征空间中散点图的分布的特点,本文对传统的fcm聚类算法进行改进,并且加入先验信息之后,将原来的非监督的聚类变成一种半监督的聚类方法,通过与已标签的样本进行相似性比较,能有效地提高聚类算法的准确度。