/** * Licensed to the Apache Software Foundation (ASF) under one or more * contributor license agreements. See the NOTICE file distributed with * this work for additional information regarding copyright ownership. * The ASF licenses this file to You under the Apache License, Version 2.0 * (the "License"); you may not use this file except in compliance with * the License. You may obtain a copy of the License at * * http://www.apache.org/licenses/LICENSE-2.0 * * Unless required by applicable law or agreed to in writing, software * distributed under the License is distributed on an "AS IS" BASIS, * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. * See the License for the specific language governing permissions and * limitations under the License. */ package org.apache.mahout.cf.taste.impl.eval; import org.apache.mahout.cf.taste.common.TasteException; import org.apache.mahout.cf.taste.eval.RecommenderBuilder; import org.apache.mahout.cf.taste.eval.RecommenderEvaluator; import org.apache.mahout.cf.taste.impl.TasteTestCase; import org.apache.mahout.cf.taste.impl.recommender.slopeone.SlopeOneRecommender; import org.apache.mahout.cf.taste.model.DataModel; import org.apache.mahout.cf.taste.recommender.Recommender; import org.junit.Test; public final class AverageAbsoluteDifferenceRecommenderEvaluatorTest extends TasteTestCase { @Test public void testEvaluate() throws Exception { DataModel model = getDataModel(); RecommenderBuilder builder = new RecommenderBuilder() { @Override public Recommender buildRecommender(DataModel dataModel) throws TasteException { return new SlopeOneRecommender(dataModel); } }; RecommenderEvaluator evaluator = new AverageAbsoluteDifferenceRecommenderEvaluator(); double eval = evaluator.evaluate(builder, null, model, 0.85, 1.0); assertEquals(0.3833333055178324, eval, EPSILON); } }