有人能解释一下数据挖掘中分类和聚类的区别吗?

如果可以,请给出两者的例子以理解主旨。


当前回答

如果你试图将大量的文件归档到你的书架上(根据日期或文件的其他规格),你是在分类。

如果要从这组工作表创建集群,则意味着工作表之间有一些类似的东西。

其他回答

通常,在分类中,您有一组预定义的类,并希望知道新对象属于哪个类。

聚类尝试将一组对象分组,并发现对象之间是否存在某种关系。

在机器学习的背景下,分类是监督学习,聚类是无监督学习。

也可以看看维基百科上的分类和聚类。

如果你试图将大量的文件归档到你的书架上(根据日期或文件的其他规格),你是在分类。

如果要从这组工作表创建集群,则意味着工作表之间有一些类似的东西。

首先,像这里的许多回答一样:分类是有监督的学习,聚类是无监督的。这意味着:

Classification needs labeled data so the classifiers can be trained on this data, and after that start classifying new unseen data based on what he knows. Unsupervised learning like clustering does not uses labeled data, and what it actually does is to discover intrinsic structures in the data like groups. Another difference between both techniques (related to the previous one), is the fact that classification is a form of discrete regression problem where the output is a categorical dependent variable. Whereas clustering's output yields a set of subsets called groups. The way to evaluate these two models is also different for the same reason: in classification you often have to check for the precision and recall, things like overfitting and underfitting, etc. Those things will tell you how good is the model. But in clustering you usually need the vision of and expert to interpret what you find, because you don't know what type of structure you have (type of group or cluster). That's why clustering belongs to exploratory data analysis. Finally, i would say that applications are the main difference between both. Classification as the word says, is used to discriminate instances that belong to a class or another, for example a man or a woman, a cat or a dog, etc. Clustering is often used in the diagnosis of medical illness, discovery of patterns, etc.

我是一个数据挖掘的新手,但正如我的课本所说,分类应该是监督学习,而聚类应该是非监督学习。监督学习和无监督学习之间的区别可以在这里找到。

通过聚类,可以用所需的属性(如数量、形状和提取的聚类的其他属性)对数据进行分组。而在分类中,组的数量和形状是固定的。 大多数聚类算法都给出了聚类个数作为参数。然而,有一些方法可以找出合适的集群数量。