贝叶斯并行分类分析

1 贝叶斯训练器

所在包：Package org.apache.mahout.classifier.bayes实现机制

The implementation is divided up into three parts:

The Trainer -- responsible for doing the counting of the words and the labels

The Model -- responsible for holding the training data in a useful way

The Classifier -- responsible for using the trainers output to determine the category of previously unseen documents

1训练器

The trainer is manifested in several classes:

BayesDriver

创建Hadoop贝叶斯作业，输出模型，这个类封装了4个map/reduce类。

common.BayesFeatureDriver

common.BayesTfIdfDriver

common.BayesWeightSummerDriver

BayesThetaNormalizerDriver

训练器的输入是KeyValueTextInputFormat格式，第一个字符时类标签，剩余的是特征（单词），如下面的格式：

hockey puck stick goalie forward defenseman referee ice checking slapshot helmet football field football pigskin referee helmet turf tackle 

hockey 和football 是类标签，剩下的是特征。

2模型