摘要：
From wikipedia.org英文版，我主要将其改变成中文。 BM25（Best Match25）是在信息检索系统中根据提出的query对document进行评分的算法。It is based on theprobabilistic retrieval frameworkdeveloped in the 1970s and 1980s byStephen E. Robertson,Karen Spärck Jones, and others.BM25算法首先由OKapi系统实现，所以又称为OKapi BM25。 BM25属于bag-of-words模型，bag-of-words 阅读全文
摘要：
TF-IDF的全称为：term frequence|inverse document frequence，它是揭示一个词对文档重要性的数字统计。From wikipedia.orgThetf*idfweight (term frequency–inverse document frequency, a.k.a.TF-IDF) is a numerical statistic which reflects how important a word is to adocumentin a collection orcorpus. It is often used as a weighting fa 阅读全文