机器学习中的特征选择降维Dimensionality Reduction by Feature Selection in Machine Learning |
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课程网址: | http://videolectures.net/slsfs05_mladenic_drfsm/ |
主讲教师: | Dunja Mladenić |
开课单位: | 约瑟夫·斯特凡学院 |
开课时间: | 2007-02-25 |
课程语种: | 英语 |
中文简介: | 降维是机器学习中常用的一个步骤,特别是在处理高维特征空间时。将原始特征空间映射到一个新的降维线性空间上,并在新的空间中给出了机器学习算法要使用的例子。映射通常通过选择原始特征的子集或/和构造一些新特征来执行。这个过程涉及第一种方法,特征子集选择。我们简要概述了机器学习中常用的特征子集选择技术,并对文本数据机器学习中使用的特征子集选择进行了更详细的描述。通过对从网络上采集到的实际数据进行实验比较,说明了文档分类方法的性能。 |
课程简介: | Dimensionality reduction is a commonly used step in machine learning, especially when dealing with a high dimensional space of features. The original feature space is mapped onto a new, reduced dimensioanllyity space and the examples to be used by machine learning algorithms are represented in that new space. The mapping is usually performed either by selecting a subset of the original features or/and by constructing some new features. This persentation deals with the first approach, feature subset selection. We provide a brief overview of the feature subset selection techniques that are commonly used in machine learning and give a more detailed description of feature subset selection used in machine learning on text data. Performance of some methods used is document categorization is illustrated by providing experimental comparison on real-world data collected from the Web. |
关 键 词: | 计算机科学; 机器学习; 预处理 |
课程来源: | 视频讲座网 |
最后编审: | 2020-07-28:yumf |
阅读次数: | 25 |