Fast Ranking with Additive Ensembles of Oblivious and Non-Oblivious Regression Trees
Fast Ranking with Additive Ensembles of Oblivious and Non-Oblivious Regression Trees
复制标题
使用遗忘和非遗忘回归树的可加集成进行快速排序
DOI:
10.1145/2987380
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发表时间:
2016
期刊:
影响因子:
--
通讯作者:
Rossano Venturini
中科院分区:
文献类型:
--
作者:
Domenico Dato;C. Lucchese;F. M. Nardini;S. Orlando;R. Perego;N. Tonellotto;Rossano Venturini
Learning-to-Rank models based on additive ensembles of regression trees have been proven to be very effective for scoring query results returned by large-scale Web search engines. Unfortunately, the computational cost of scoring thousands of candidate documents by traversing large ensembles of trees is high. Thus, several works have investigated solutions aimed at improving the efficiency of document scoring by exploiting advanced features of modern CPUs and memory hierarchies. In this article, we present QuickScorer, a new algorithm that adopts a novel cache-efficient representation of a given tree ensemble, performs an interleaved traversal by means of fast bitwise operations, and supports ensembles of oblivious trees. An extensive and detailed test assessment is conducted on two standard Learning-to-Rank datasets and on a novel very large dataset we made publicly available for conducting significant efficiency tests. The experiments show unprecedented speedups over the best state-of-the-art baselines ranging from 1.9 × to 6.6 × . The analysis of low-level profiling traces shows that QuickScorer efficiency is due to its cache-aware approach in terms of both data layout and access patterns and to a control flow that entails very low branch mis-prediction rates.