Example usage for org.apache.mahout.cf.taste.recommender IDRescorer IDRescorer

Introduction

In this page you can find the example usage for org.apache.mahout.cf.taste.recommender IDRescorer IDRescorer.

Prototype

IDRescorer

Source Link

Usage

From source file:com.rssrecommender.services.MahoutService.java

@PostConstruct
public void init() {
    try {//from   w w w  .jav a 2 s  .c o  m
        dataSource = new MysqlConnectionPoolDataSource();

        dataSource.setServerName("localhost");
        dataSource.setUser("root");
        dataSource.setPassword("1234");
        dataSource.setDatabaseName("rss_rec");
        dataSource.setCachePreparedStatements(true);
        dataSource.setCachePrepStmts(true);
        dataSource.setCacheResultSetMetadata(true);
        dataSource.setAlwaysSendSetIsolation(true);
        dataSource.setElideSetAutoCommits(true);

        model = new MySQLJDBCDataModel(dataSource, "user_likes_article", "user_id", "article_id", "rating",
                null);
        m = new ReloadFromJDBCDataModel(model);
        is = new PearsonCorrelationSimilarity(m);

        //            ItemSimilarity is = new EuclideanDistanceSimilarity(model, Weighting.WEIGHTED);
        //            cis = new CachingItemSimilarity(is, 150);
        r = new GenericItemBasedRecommender(m, is);
        rsr = new IDRescorer() {

            @Override
            public double rescore(long id, double originalScore) {
                Article a = af.find((int) id);
                long diff = Calendar.getInstance().getTimeInMillis() - a.getDate().getTime() + 1;
                double time = 1.0d / (diff / (1000 * 360 * 12)); // half day period since feeds are update regularly
                return originalScore * time;
            }

            @Override
            public boolean isFiltered(long id) {
                //always rescore
                return false;
            }
        };
        //            Optimizer optimizer = new ConjugateGradientOptimizer();
        //            r = new KnnItemBasedRecommender(m, is, optimizer, 5);
        //          
    } catch (TasteException ex) {
        Logger.getLogger(MahoutService.class.getName()).log(Level.SEVERE, null, ex);
    }
}

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From source file:net.myrrix.online.example.rescorer.FilterHalfRescorerProvider.java

License:Apache License

@Override
public IDRescorer getRecommendRescorer(final long[] userIDs, MyrrixRecommender recommender, String... args) {
    final boolean odd = args.length > 0 && "odd".equalsIgnoreCase(args[0]);
    return new IDRescorer() {
        @Override//w w w  . j a v a 2  s .c  o  m
        public double rescore(long itemID, double score) {
            for (long userID : userIDs) {
                if (odd == ((userID & 0x01) == 1)) {
                    return Double.NaN;
                }
            }
            return isFiltered(itemID) ? Double.NaN : 10.0 * score;
        }

        @Override
        public boolean isFiltered(long itemID) {
            return odd == ((itemID & 0x01) == 1);
        }
    };
}

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From source file:net.myrrix.online.example.rescorer.FilterHalfRescorerProvider.java

License:Apache License

@Override
public IDRescorer getRecommendToAnonymousRescorer(final long[] itemIDs, MyrrixRecommender recommender,
        String... args) {//w  w  w  . j ava 2 s  .co  m
    final boolean odd = args.length > 0 && "odd".equalsIgnoreCase(args[0]);
    return new IDRescorer() {
        @Override
        public double rescore(long itemID, double score) {
            for (long anItemID : itemIDs) {
                if (odd == ((anItemID & 0x01) == 1)) {
                    return Double.NaN;
                }
            }
            return isFiltered(itemID) ? Double.NaN : 10.0 * score;
        }

        @Override
        public boolean isFiltered(long itemID) {
            return odd == ((itemID & 0x01) == 1);
        }
    };
}

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From source file:net.myrrix.online.example.rescorer.FilterHalfRescorerProvider.java

License:Apache License

@Override
public IDRescorer getMostPopularItemsRescorer(MyrrixRecommender recommender, String... args) {
    final boolean odd = args.length > 0 && "odd".equalsIgnoreCase(args[0]);
    return new IDRescorer() {
        @Override//from ww  w .jav a 2 s .c  o  m
        public double rescore(long itemID, double score) {
            return isFiltered(itemID) ? Double.NaN : 10.0 * score;
        }

        @Override
        public boolean isFiltered(long itemID) {
            return odd == ((itemID & 0x01) == 1);
        }
    };
}

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