Mahout 基于用户的协同过滤推荐简单实现

Javase小例子

1：用户推荐数据：

用户id   商品id   评分

1,01,2.0
1,02,1.0
1,03,2.5
1,04,5.0
1,05,5.0
2,01,1.0
2,03,4.5
2,04,4.0
2,06,3.0
3,01,3.5
3,04,2.0
3,05,3.0
3,07,5.0
4,01,5.0
4,03,3.0
4,05,3.5
4,07,4.0
4,08,6.0
5,01,4.0
5,02,3.0
5,04,2.0
5,09,4.0
5,05,3.5
5,06,4.0

2：maven依赖：

http://mvnrepository.com/artifact/org.apache.mahout/mahout-core

http://mvnrepository.com/artifact/org.apache.mahout/mahout-integration

3：主程序代码（）

import org.apache.mahout.cf.taste.common.TasteException;
import org.apache.mahout.cf.taste.impl.model.file.FileDataModel;
import org.apache.mahout.cf.taste.impl.neighborhood.NearestNUserNeighborhood;
import org.apache.mahout.cf.taste.impl.recommender.GenericUserBasedRecommender;
import org.apache.mahout.cf.taste.impl.similarity.EuclideanDistanceSimilarity;
import org.apache.mahout.cf.taste.impl.similarity.PearsonCorrelationSimilarity;
import org.apache.mahout.cf.taste.model.DataModel;
import org.apache.mahout.cf.taste.neighborhood.UserNeighborhood;
import org.apache.mahout.cf.taste.recommender.RecommendedItem;
import org.apache.mahout.cf.taste.recommender.Recommender;
import org.apache.mahout.cf.taste.similarity.UserSimilarity;

import java.io.File;
import java.io.IOException;
import java.util.List;

public class C {
    public static void main(String[] args) {
        //准备数据
        File file=new File("D:\\data\\data.txt");
        DataModel dataModel= null;
        try {
            //加载数据
            dataModel = new FileDataModel(file);
            //计算相似度这里采用欧式距离
            UserSimilarity similarity=new EuclideanDistanceSimilarity(dataModel);
            //基于5个邻居计算相似度
            UserNeighborhood neighborhood=new NearestNUserNeighborhood(5,similarity,dataModel);
            //基于用户协同推荐
            Recommender recommender=new GenericUserBasedRecommender(dataModel,neighborhood,similarity);
            int userid=3;
            //给用户id为3的推荐两项项目。
            List<RecommendedItem> list=recommender.recommend(userid,2);
            //打印输出
            for (RecommendedItem item:list){
                System.out.println(item);
                System.out.println(item.getItemID());
                System.out.println(item.getValue());
                System.out.println("\n");
            }
        } catch (IOException e) {
            System.out.println("filed");
            e.printStackTrace();
        } catch (TasteException e) {
            System.out.println("filed");
            e.printStackTrace();
        }
    }
}

4：实现效果：