RankLib.jar 是一個學習排名(Learning to rank)算法的庫,目前已經實現了以下幾種算法:java
Usage: java -jar RankLib.jar <Params> Params: [+] Training (+ tuning and evaluation) # 訓練數據 -train <file> Training data # 指定排名算法 -ranker <type> Specify which ranking algorithm to use 0: MART (gradient boosted regression tree) 1: RankNet 2: RankBoost 3: AdaRank 4: Coordinate Ascent 6: LambdaMART 7: ListNet 8: Random Forests 9: Linear regression (L2 regularization) # 特徵描述文件,列出要學習的特徵,每行一個特徵,默認使用全部特徵 [ -feature <file> ] Feature description file: list features to be considered by the learner, each on a separate line If not specified, all features will be used. # [ -metric2t <metric> ] Metric to optimize on the training data. Supported: MAP, NDCG@k, DCG@k, P@k, RR@k, ERR@k (default=ERR@10) [ -gmax <label> ] Highest judged relevance label. It affects the calculation of ERR (default=4, i.e. 5-point scale {0,1,2,3,4}) [ -silent ] Do not print progress messages (which are printed by default) # 是否在驗證數據集上調整模型 [ -validate <file> ] Specify if you want to tune your system on the validation data (default=unspecified) If specified, the final model will be the one that performs best on the validation data # 訓練-驗證數據集的分割比例 [ -tvs <x \in [0..1]> ] If you don't have separate validation data, use this to set train-validation split to be (x)(1.0-x) # 學習模型保存到指定文件 [ -save <model> ] Save the model learned (default=not-save) # 是否要在數據上測試訓練的模型 [ -test <file> ] Specify if you want to evaluate the trained model on this data (default=unspecified) # 訓練-測試數據集的分割比例 [ -tts <x \in [0..1]> ] Set train-test split to be (x)(1.0-x). -tts will override -tvs # 默認與 metric2t 一致 [ -metric2T <metric> ] Metric to evaluate on the test data (default to the same as specified for -metric2t) # 歸一化特徵向量,方法包括求和歸一化,均值/標準差歸一化,最大值/最小值歸一化 [ -norm <method>] Normalize all feature vectors (default=no-normalization). Method can be: sum: normalize each feature by the sum of all its values zscore: normalize each feature by its mean/standard deviation linear: normalize each feature by its min/max values # 在訓練數據集上執行交叉驗證 [ -kcv <k> ] Specify if you want to perform k-fold cross validation using the specified training data (default=NoCV) -tvs can be used to further reserve a portion of the training data in each fold for validation # 交叉驗證訓練庫模型的目錄 [ -kcvmd <dir> ] Directory for models trained via cross-validation (default=not-save) [ -kcvmn <model> ] Name for model learned in each fold. It will be prefix-ed with the fold-number (default=empty) [-] RankNet-specific parameters # 特定參數 # 訓練迭代次數 [ -epoch <T> ] The number of epochs to train (default=100) # 隱含層個數 [ -layer <layer> ] The number of hidden layers (default=1) # 每層隱含節點個數 [ -node <node> ] The number of hidden nodes per layer (default=10) # 學習率 [ -lr <rate> ] Learning rate (default=0.00005) [-] RankBoost-specific parameters # 特定參數 # 訓練迭代次數 [ -round <T> ] The number of rounds to train (default=300) # 搜索的閾值候選個數 [ -tc <k> ] Number of threshold candidates to search. -1 to use all feature values (default=10) [-] AdaRank-specific parameters # 特定參數 # 訓練迭代次數 [ -round <T> ] The number of rounds to train (default=500) # [ -noeq ] Train without enqueuing too-strong features (default=unspecified) # 連續兩輪學習之間的偏差 [ -tolerance <t> ] Tolerance between two consecutive rounds of learning (default=0.002) # 一個特徵能夠被連續選擇而不改變性能的最大次數 [ -max <times> ] The maximum number of times can a feature be consecutively selected without changing performance (default=5) [-] Coordinate Ascent-specific parameters # 特定參數 [ -r <k> ] The number of random restarts (default=5) [ -i <iteration> ] The number of iterations to search in each dimension (default=25) [ -tolerance <t> ] Performance tolerance between two solutions (default=0.001) [ -reg <slack> ] Regularization parameter (default=no-regularization) [-] {MART, LambdaMART}-specific parameters # 特定參數 # 樹的個數 [ -tree <t> ] Number of trees (default=1000) # 一個葉子的樣本個數 [ -leaf <l> ] Number of leaves for each tree (default=10) # 學習率 [ -shrinkage <factor> ] Shrinkage, or learning rate (default=0.1) # 樹分割時的候選特徵個數 [ -tc <k> ] Number of threshold candidates for tree spliting. -1 to use all feature values (default=256) # 一個葉子最少的樣本個數 [ -mls <n> ] Min leaf support -- minimum #samples each leaf has to contain (default=1) [ -estop <e> ] Stop early when no improvement is observed on validaton data in e consecutive rounds (default=100) [-] ListNet-specific parameters [ -epoch <T> ] The number of epochs to train (default=1500) [ -lr <rate> ] Learning rate (default=0.00001) [-] Random Forests-specific parameters # 隨機森林特定參數 [ -bag <r> ] Number of bags (default=300) # 子集採樣率 [ -srate <r> ] Sub-sampling rate (default=1.0) # 特徵採樣率 [ -frate <r> ] Feature sampling rate (default=0.3) [ -rtype <type> ] Ranker to bag (default=0, i.e. MART) # 樹個數 [ -tree <t> ] Number of trees in each bag (default=1) # 每棵樹的葉節點個數 [ -leaf <l> ] Number of leaves for each tree (default=100) # 學習率 [ -shrinkage <factor> ] Shrinkage, or learning rate (default=0.1) # 樹分割時使用的候選特徵閾值個數 [ -tc <k> ] Number of threshold candidates for tree spliting. -1 to use all feature values (default=256) [ -mls <n> ] Min leaf support -- minimum #samples each leaf has to contain (default=1) [-] Linear Regression-specific parameters [ -L2 <reg> ] L2 regularization parameter (default=1.0E-10) [+] Testing previously saved models # 測試已保存的模型 # 加載模型 -load <model> The model to load Multiple -load can be used to specify models from multiple folds (in increasing order), in which case the test/rank data will be partitioned accordingly. # 測試數據 -test <file> Test data to evaluate the model(s) (specify either this or -rank but not both) # 對指定文件中的樣本排序,與 -test 不能同時使用 -rank <file> Rank the samples in the specified file (specify either this or -test but not both) [ -metric2T <metric> ] Metric to evaluate on the test data (default=ERR@10) [ -gmax <label> ] Highest judged relevance label. It affects the calculation of ERR (default=4, i.e. 5-point scale {0,1,2,3,4}) [ -score <file>] Store ranker's score for each object being ranked (has to be used with -rank) # 打印單個排名列表上的性能(必須與 -test 一塊兒使用) [ -idv <file> ] Save model performance (in test metric) on individual ranked lists (has to be used with -test) # 特徵歸一化 [ -norm ] Normalize feature vectors (similar to -norm for training/tuning)
指定訓練數據的文件,訓練數據格式:node
label qid:$id $featureid:$featurevalue $featureid:$featurevalue ... # description
每行表明一個樣本,相同查詢請求的樣本的 qid 相同,label 表示該樣本和該查詢請求的相關程度,description 描述信息,不參與訓練計算。算法
指定排名算法網絡
指定樣本的特徵定義文件,格式以下:dom
feature1 feature2 ... # featureK(該特徵不參與分析)
指定信息檢索中的評價指標,包括:
MAP, NDCG@k, DCG@k, P@k, RR@k, ERR@kide
java -jar bin/RankLib.jar -train MQ2008/Fold1/train.txt -test MQ2008/Fold1/test.txt -validate MQ2008/Fold1/vali.txt -ranker 6 -metric2t NDCG@10 -metric2T ERR@10 -save mymodel.txt
命令解釋 >>>
訓練數據:MQ2008/Fold1/train.txt
測試數據:MQ2008/Fold1/test.txt
驗證數據:MQ2008/Fold1/vali.txt
排名算法:6,LambdaMART
評估指標:NDCG,取排名前 10 個數據進行計算
測試數據評估指標:ERR,取排名前 10 個數據進行計算
保存模型:mymodel.txt性能
java -jar bin/RankLib.jar -train MQ2008/Fold1/train.txt -ranker 4 -kcv 5 -kcvmd models/ -kcvmn ca -metric2t NDCG@10 -metric2T ERR@10
按順序將訓練數據拆分5等份,第 i 份數據做爲第 i 摺疊的測試數據,第 i 摺疊的訓練數據則是由其餘摺疊的數據組成。學習
java -cp bin/RankLib.jar ciir.umass.edu.features.FeatureManager -input MQ2008/Fold1/train.txt -output mydata/ -shuffle
將訓練數據 train.txt 從新洗牌存儲在 mydata/ 目錄下 train.txt.shuffled測試
java -cp bin/RankLib.jar ciir.umass.edu.features.FeatureManager -input MQ2008/Fold1/train.txt.shuffled -output mydata/ -k 5
java -jar bin/RankLib.jar -load mymodel.txt -test MQ2008/Fold1/test.txt -metric2T ERR@10
java -jar bin/RankLib.jar -test MQ2008/Fold1/test.txt -metric2T NDCG@10 -idv output/baseline.ndcg.txt java -jar bin/RankLib.jar -load ca.model.txt -test MQ2008/Fold1/test.txt -metric2T NDCG@10 -idv output/ca.ndcg.txt java -jar bin/RankLib.jar -load lm.model.txt -test MQ2008/Fold1/test.txt -metric2T NDCG@10 -idv output/lm.ndcg.txt
輸出文件中包含了每條查詢的 NDCG@10 指標值,以及全部查詢的綜合指標,例如:ui
NDCG@10 170 0.0 NDCG@10 176 0.6722390270733757 NDCG@10 177 0.4772656487866462 NDCG@10 178 0.539003131276382 NDCG@10 185 0.6131471927654585 NDCG@10 189 1.0 NDCG@10 191 0.6309297535714574 NDCG@10 192 1.0 NDCG@10 194 0.2532778777010656 NDCG@10 197 1.0 NDCG@10 200 0.6131471927654585 NDCG@10 204 0.4772656487866462 NDCG@10 207 0.0 NDCG@10 209 0.123151194370365 NDCG@10 221 0.39038004999210174 NDCG@10 all 0.5193204478059303
而後再進行對比:
java -cp RankLib.jar ciir.umass.edu.eval.Analyzer -all output/ -base baseline.ndcg.txt > analysis.txt
對比結果 analysis.txt 以下:
Overall comparison ------------------------------------------------------------------------ System Performance Improvement Win Loss p-value baseline_ndcg.txt [baseline] 0.093 LM_ndcg.txt 0.2863 +0.1933 (+207.8%) 9 1 0.03 CA_ndcg.txt 0.5193 +0.4263 (+458.26%) 12 0 0.0 Detailed break down ------------------------------------------------------------------------ [ < -100%) [-100%,-75%) [-75%,-50%) [-50%,-25%) [-25%,0%) (0%,+25%] (+25%,+50%] (+50%,+75%] (+75%,+100%] ( > +100%] LM_ndcg.txt 0 0 1 0 0 4 2 2 1 0 CA_ndcg.txt 0 0 0 0 0 1 6 2 3 0
java -jar RankLib.jar -load mymodel.txt -rank myResultLists.txt -score myScoreFile.txt
myScoreFile.txt 文件中只是增長了一列,表示從新計算的排名評分,須要本身另外根據該評分排序獲取新的排名順序。
1 0 -7.528650760650635 1 1 2.9022061824798584 1 2 -0.700125515460968 1 3 2.376657485961914 1 4 -0.29666265845298767 1 5 -2.038628101348877 1 6 -5.267711162567139 1 7 -2.022146463394165 1 8 0.6741248369216919 ...