1、毕业设计论文任务书 题目 基于贝叶斯的文本自动分类的研究和实现 专业 学号 姓名主要内容、根本要求、主要参考资料等:近年来随着Internet的大规模普及和企业信息化程度的提高,有越来越多的信息积累,而需要信息的人还没有特别方便的工具去从来自异构数据源的大规模的文本信息资源中提取符合需要的简洁、精炼、可理解的知识,文本挖掘正是解决这一问题的一个方法。本课题研究基于贝叶斯的文本分类系统,可以用于以下领域和系统中:企业知识门户、信息增值效劳、智能搜索引擎 、数字图书馆 、情报分析 、信息安全和过滤、电子商务系统。文本自动分类不需人工干预的自动分类技术,有效提高非结构化信息资源的加工效率。利用朴素贝
2、叶斯分类文法的分类器,分析已经手动分类的文本,根据文本内容计算分类条件概率,再利用训练好的分类器分析未分类的文本,根据分类器算出的所属领域概率最大的进行分类。本课题任务要求:1) 学习关于朴素贝叶斯分类文法,查找相关的资料以供参考;2) 实现朴素贝叶斯分类文法的分类器;3) 人工对样本数据进行分类和标注;4) 利用贝叶斯分类文法的分类器,利用样本进行训练,然后对分类数据进行自动分类;5) 根据分类结果,调整分类阈值,弥补分类器的缺乏。6) 根据实验数据和结果,按时完成毕业设计论文。主要参考资料:贝叶斯分类算法的论文和资料,未分类文本语料。完成期限: 指导教师签章: 专业负责人签章:年 月 日随
3、着计算机技术和通讯技术的飞速开展,人们可以获得越来越多的数字化信息,但同时也需要投入更多的时间对信息进行组织和管理。为了减轻这种负担,人们开始研究使用计算机对文本进行自动分类。文本自动分类就是在给定的分类体系下,让计算机根据文本的内容确定与它相关联的类别。自动文本分类是人工智能技术和信息获取技术相结合的研究领域。随着网络的开展,大量的文档数据涌现在网上,用于处理海量数据的自动文本分类技术变得越来越重要,已逐渐成为处理和组织大量文档数据的关键技术。通过分析kNN(k Nearest Neighbor)、朴素贝叶斯(Naive Bayes)、SVM(Support Vector Machine)三
4、种文本分类方法的优点和缺点,发现朴素贝叶斯分类器速度极快,具有最小的出错率,可在线化实现等优点,并对该分类方法进行了理论分析和实验比照,实验结果说明这种文本分类模型是高效的可行的。本文首先介绍了基于贝叶斯的文本自动分类的研究和实现的背景,并且表达了相关问题的概念知识,包括文本分类和中文分词等;其次,对相关的理论知识做了讲解,包括先验概率、条件概率、贝叶斯理论、贝叶斯算法等;第三,对如何实现文本分类进行了概述以及整体讲解,通过给出流程图,可以更直观的了解实现的过程;第四,详细介绍了实现本课题所用到的重要工具,包括JBuilder2023开发工具和全文检索引擎Lucene以及Java平台;第五,在
5、前期工作根底上,给出了详细的实现过程,包括单文本分类和多文本分类以及相关具体操作;最后,通过屡次大量重复试验,得出了实验数据,在此通过表格的形式,直观的给出了实验结果。本课题研究基于贝叶斯的文本分类系统,根据所讨论的算法构造了贝叶斯文本自动别离器,并做出详尽的训练测试,从最终的试验结果可以看出,贝叶斯算法简单、性能优越,即使在不考虑贝叶斯假设的前提下,仍然取得良好的分类性能。关键字:文本自动分类 ,贝叶斯分类 ,分类文本语料库。AbstractWith the computer technology and the rapid development of communication tech
6、nology, people can get more and more digital information, but it also needs to devote more time to organize and manage information. In order to alleviate that burden, people began to study the use of computers for automatic classification of text. Automatic text categorization is the classification
7、of a given system, the computer determined in accordance with the contents of the text associated with its category. Automatic text classification is the artificial intelligence technology and access to information technology research field. With the development of network, data on the emergence of
8、a large number of documents online, to deal with massive data technology of automatic text classification is becoming increasingly important, has become an increasingly large number of document processing and organization of the key technologies of data.By analyzing the k Nearest Neighbor、Naive Baye
9、s、Support Vector Machine method of text classification in three strengths and weaknesses found in Naive Bayesian classifier speed, with the smallest error rate, can achieve the advantages of online technology, and the classification of the theoretical analysis and experimental comparison, experiment
10、al results show that the text categorization model is feasible and efficient. This paper first introduces the Bayesian-based text categorization of the research and realization of the background and describes the issues related to the concept of knowledge, including text classification and Chinese w
11、ord segmentation . Second, the relevant theoretical knowledge to do the explaining, including a priori probability, conditional probability, Bayesian theory, the Bayesian algorithm . Third, on how to achieve the outlined text classification as well as on the whole, through the given flow chart, you
12、can achieve a more intuitive understanding of the process. Fourth, in detail on achieving this important task by use of tools, including development tools and JBuilder2023 full-text search engine Lucene and Java platform.Fifth, prior to the adoption of the work detailed in this paper the realization
13、 of the process, including single-and multi-text classification text categorization and related specific operations; Finally, a large number of repeat tests many times, the experimental data obtained in this form through the form, intuitive experimental results are given.The research based on Bayesi
14、an text classification system, according to the algorithm discussed in the text automatically constructed Bayesian separator and training to make a detailed test results from the final we can see that the Bayesian algorithm is simple, superior performance, even without taking into account the assump
15、tion that the premise of Bayesian still achieve good classification performance. Keywords: Automatic Text Categorization, Bayesian Classifier, Classification of text corpora.目录1.绪论21.1研究背景21.2 文本分类的研究现状21.3分类的含义31.4文本分类的含义31.5自动分类31.6中文分词31.7中文分词的意义和作用41.8中文分词的应用41.9 本文的组织42.条件概率62.1 条件概率定义62.2 全概率公式和贝叶斯公式62.3贝叶斯学习理论62.4朴素贝叶斯分类72.5贝叶斯文本分类算法92.6文本自动分类的特点103.设计概述113.1流程图113.2概要设计144.系统开发环境154.1 JAVA154.2开放源代码的全文检索引擎Lucene简介165.贝叶斯的文本自动分类的分析与设计195.1 引言195.2 详细设计195.3 程序实现295.4试验数据356结论36全文总结36未来展望36致谢37参考文献381.绪论1.1研究背景我们正处在一个信息