おそらくまばらなデータ セットでレコメンダー アルゴリズムを評価しようとしていますが、約 20,000 人のユーザーに対して 341 アイテムしかありません。すべての類似性アルゴリズムを評価したいだけです。私はほとんどすべてのユーザーベースの推奨事項を試しましたが、それらのすべてについて、評価者 (AverageAbsoluteDifferenceRecommenderEvaluatorまたはルート平均二乗スコアリング評価者) に関係なく、評価者からこの情報を取得しています。これはxXXX ケースでは推奨できません。ただし、最終出力にはまだいくつかの結果があります。私の評価者の出力は次のとおりです。
3/06/17 14:11:35 INFO eval.AbstractDifferenceRecommenderEvaluator: Beginning evaluation using 0.7 of org.apache.mahout.cf.taste.impl.model.jdbc.PostgreSQLJDBCDataModel@44303e7b
13/06/17 14:15:17 INFO model.GenericDataModel: Processed 10000 users
13/06/17 14:15:17 INFO model.GenericDataModel: Processed 20000 users
13/06/17 14:15:17 INFO model.GenericDataModel: Processed 20530 users
13/06/17 14:15:17 INFO eval.AbstractDifferenceRecommenderEvaluator: Beginning evaluation of 11240 users
13/06/17 14:15:17 INFO eval.AbstractDifferenceRecommenderEvaluator: Starting timing of 11240 tasks in 4 threads
13/06/17 14:15:17 INFO eval.AbstractDifferenceRecommenderEvaluator: Average time per recommendation: 4ms
13/06/17 14:15:17 INFO eval.AbstractDifferenceRecommenderEvaluator: Approximate memory used: 57MB / 101MB
13/06/17 14:15:17 INFO eval.AbstractDifferenceRecommenderEvaluator: Unable to recommend in 3 cases
13/06/17 14:15:19 INFO eval.AbstractDifferenceRecommenderEvaluator: Average time per recommendation: 4ms
13/06/17 14:15:19 INFO eval.AbstractDifferenceRecommenderEvaluator: Approximate memory used: 48MB / 99MB
13/06/17 14:15:19 INFO eval.AbstractDifferenceRecommenderEvaluator: Unable to recommend in 882 cases
13/06/17 14:15:20 INFO eval.AbstractDifferenceRecommenderEvaluator: Average time per recommendation: 5ms
13/06/17 14:15:20 INFO eval.AbstractDifferenceRecommenderEvaluator: Approximate memory used: 33MB / 109MB
13/06/17 14:15:20 INFO eval.AbstractDifferenceRecommenderEvaluator: Unable to recommend in 1787 cases
13/06/17 14:15:22 INFO eval.AbstractDifferenceRecommenderEvaluator: Average time per recommendation: 5ms
13/06/17 14:15:22 INFO eval.AbstractDifferenceRecommenderEvaluator: Approximate memory used: 41MB / 86MB
13/06/17 14:15:22 INFO eval.AbstractDifferenceRecommenderEvaluator: Unable to recommend in 2687 cases
13/06/17 14:15:23 INFO eval.AbstractDifferenceRecommenderEvaluator: Average time per recommendation: 5ms
13/06/17 14:15:23 INFO eval.AbstractDifferenceRecommenderEvaluator: Approximate memory used: 38MB / 98MB
13/06/17 14:15:23 INFO eval.AbstractDifferenceRecommenderEvaluator: Unable to recommend in 3569 cases
13/06/17 14:15:24 INFO eval.AbstractDifferenceRecommenderEvaluator: Average time per recommendation: 5ms
13/06/17 14:15:24 INFO eval.AbstractDifferenceRecommenderEvaluator: Approximate memory used: 28MB / 93MB
13/06/17 14:15:24 INFO eval.AbstractDifferenceRecommenderEvaluator: Unable to recommend in 4465 cases
13/06/17 14:15:26 INFO eval.AbstractDifferenceRecommenderEvaluator: Average time per recommendation: 5ms
13/06/17 14:15:26 INFO eval.AbstractDifferenceRecommenderEvaluator: Approximate memory used: 41MB / 88MB
13/06/17 14:15:26 INFO eval.AbstractDifferenceRecommenderEvaluator: Unable to recommend in 5420 cases
13/06/17 14:15:27 INFO eval.AbstractDifferenceRecommenderEvaluator: Average time per recommendation: 5ms
13/06/17 14:15:27 INFO eval.AbstractDifferenceRecommenderEvaluator: Approximate memory used: 45MB / 90MB
13/06/17 14:15:27 INFO eval.AbstractDifferenceRecommenderEvaluator: Unable to recommend in 6317 cases
13/06/17 14:15:28 INFO eval.AbstractDifferenceRecommenderEvaluator: Average time per recommendation: 5ms
13/06/17 14:15:28 INFO eval.AbstractDifferenceRecommenderEvaluator: Approximate memory used: 46MB / 103MB
13/06/17 14:15:28 INFO eval.AbstractDifferenceRecommenderEvaluator: Unable to recommend in 7220 cases
13/06/17 14:15:30 INFO eval.AbstractDifferenceRecommenderEvaluator: Average time per recommendation: 5ms
13/06/17 14:15:30 INFO eval.AbstractDifferenceRecommenderEvaluator: Approximate memory used: 72MB / 102MB
13/06/17 14:15:30 INFO eval.AbstractDifferenceRecommenderEvaluator: Unable to recommend in 8145 cases
13/06/17 14:15:31 INFO eval.AbstractDifferenceRecommenderEvaluator: Average time per recommendation: 5ms
13/06/17 14:15:31 INFO eval.AbstractDifferenceRecommenderEvaluator: Approximate memory used: 67MB / 99MB
13/06/17 14:15:31 INFO eval.AbstractDifferenceRecommenderEvaluator: Unable to recommend in 9084 cases
13/06/17 14:15:33 INFO eval.AbstractDifferenceRecommenderEvaluator: Average time per recommendation: 5ms
13/06/17 14:15:33 INFO eval.AbstractDifferenceRecommenderEvaluator: Approximate memory used: 31MB / 83MB
13/06/17 14:15:33 INFO eval.AbstractDifferenceRecommenderEvaluator: Unable to recommend in 9982 cases
13/06/17 14:15:33 INFO eval.AbstractDifferenceRecommenderEvaluator: Evaluation result: 1.643042326271061
なぜ何度も表示されるのか、数字がわかりません。これは、すべてのデータの 20% を超える xxx ケースでは推奨できませんか? あるユーザーには 3 件、別のユーザーには 9892 件の推奨できないということですか?