Question

我有一个libsvm格式的数据集，其中包含重要性分数和功能的标签。 qid是查询。数据如下所示。

我想使用xgboost来创建搜索排名，但我不知道xgb.train函数的输入数据格式是什么。我已经看到用于分类和回归的数据格式。但是我的数据集具有代表组信息的查询，并且还没有计算lambda。那么如何使用xgboost api来训练我的排名模型以及所需数据的格式是什么？

此外，我想使用ndcg来评估我的模型。

非常感谢，我期待着解决方案。

0 qid:1830 1:0.002736 2:0.000000 3:0.000000 4:0.000000 5:0.002736 6:0.000000 7:0.000000 8:0.000000 9:0.000000 10:0.000000
0 qid:1830 1:0.025992 2:0.125000 3:0.000000 4:0.000000 5:0.027360 6:0.000000 7:0.000000 8:0.000000 9:0.000000 10:0.000000
0 qid:1830 1:0.001368 2:0.000000 3:0.000000 4:0.000000 5:0.001368 6:0.000000 7:0.000000 8:0.000000 9:0.000000 10:0.000000
1 qid:1830 1:0.188782 2:0.375000 3:0.333333 4:1.000000 5:0.195622 6:0.000000 7:0.000000 8:0.000000 9:0.000000 10:0.000000
1 qid:1830 1:0.077975 2:0.500000 3:0.666667 4:0.000000 5:0.086183 6:0.000000 7:0.000000 8:0.000000 9:0.000000 10:0.000000
0 qid:1830 1:0.075239 2:0.125000 3:0.333333 4:0.000000 5:0.077975 6:0.000000 7:0.000000 8:0.000000 9:0.000000 10:0.000000
1 qid:1830 1:0.079343 2:0.250000 3:0.666667 4:0.000000 5:0.084815 6:0.000000 7:0.000000 8:0.000000 9:0.000000 10:0.000000
1 qid:1830 1:0.147743 2:0.000000 3:0.000000 4:0.000000 5:0.147743 6:0.000000 7:0.000000 8:0.000000 9:0.000000 10:0.000000
0 qid:1830 1:0.058824 2:0.000000 3:0.000000 4:0.000000 5:0.058824 6:0.000000 7:0.000000 8:0.000000 9:0.000000 10:0.000000
0 qid:1830 1:0.071135 2:0.125000 3:0.333333 4:0.000000 5:0.073871 6:0.000000 7:0.000000 8:0.000000 9:0.000000 10:0.000000
1 qid:1840 1:0.007364 2:0.200000 3:1.000000 4:0.500000 5:0.013158 6:0.000000 7:0.000000 8:0.000000 9:0.000000 10:0.000000
1 qid:1840 1:0.097202 2:0.000000 3:0.000000 4:0.000000 5:0.096491 6:0.000000 7:0.000000 8:0.000000 9:0.000000 10:0.000000
2 qid:1840 1:0.169367 2:0.000000 3:0.500000 4:0.000000 5:0.169591 6:0.000000 7:0.000000 8:0.000000 9:0.000000 10:0.000000
......

Answer 1

Format in XGBoost docs

一般形式：

<line> .=. <target> <feature>:<value> <feature>:<value> ... <feature>:<value> # <docid> <inc> <prob>
<target> .=. +1 | -1 | 0 | <float> 
<feature> .=. <integer> | "qid"
<value> .=. <float>
<info> .=. <string> 
<inc> .=. <integer> 
<prob> .=. <float> 
<docid> .=. <string>

如果您想以该格式编写数据，请参阅dump_svmlight_file。

xgboost（Python版本）中lambdaMART的数据格式是什么？

1 个答案: