Coursera NLP课程第二周Assignment

作者张洋，很通俗的讲解朴素贝叶斯分类器的文章，作者的博客讲解了许多算法：http://blog.codinglabs.org/ ，值得一读。

垃圾邮件分类 K最近邻居分类器： Accuracy: 93.x% 决策树分类器： Accuracy: 93-94% 朴素贝叶斯分类器： Accuracy: 96.x% Ada-Boost分类器： Accuracy: 96.x% 支持向量机： Accuracy: 97.x% 随机森林分类器： Accuracy: 97-98.x% 调整参数可能会导致结果变化

Decision trees are particularly promising in symbolic representation and reasoning due to their comprehensible nature, which resembles the hierarchical process of human decision making. However, their drawbacks, caused by the single-tree structure, cannot be ignored. A rigid decision path may cause the majority class to overwhelm other class when dealing with imbalanced data sets, and pruning removes not only superfluous nodes, but also subtrees. The proposed learning algorithm, flexible hybrid decision forest (FHDF), mines information implicated in each instance to form logical rules on the basis of a chain rule of local mutual information, then forms different decision tree structures and decision forests later. The most credible decision path from the decision forest can be selected to make a prediction. Furthermore, functional dependencies (FDs), which are extracted from the whole data set based on association rule analysis, perform embeddedattribute selection to remove nodes rather than subtrees, thus helping to achieve different levels of knowledge representation and improve model comprehension in the framework of semi-supervised learning. Naive Bayes replaces the leaf nodes at the bottom of the tree hierarchy, where the conditional independence assumption may hold. This techniquereduces the potential for overfitting and overtraining and improves the prediction quality and generalization. Experimental results on UCI data sets demonstrate the efficacy of the proposed approach.

Matlab高斯朴素贝叶斯算法和KNN分类算法的实现。 培训和测试数据取自UCI机器学习数据存储库的“玻璃识别数据集”。数据集在Data文件夹下 注意：为了进行KNN的准确性计算，使用了留一法交叉验证。

这个是Python编写的一个情感文本分析程序，定义两种term weight实现，分别为TF 和BOOL，实现了特征选择算法。文件夹中附带数据集

本程序实现了基于朴素贝叶斯方法的文本分类，附有源代码、实验报告、可执行程序以及语料库（包括训练集和测试集）

机器学习大作业，用matlab对mnist手写字分类，包含knn bayes 和svm算法

NaiveBays朴素贝叶斯算法在JAVA中的实现

个人课设时实现的基于决策树和朴素贝叶斯算法对Adult数据集进行分类的源码！