Converting browsers into buyers • Improving web site design and usability • Improving customer retention and loyalty • Increasing cross-sell by recommending items related to the ones being considered • Helping visitors to quickly find relevant information on a website • Making results of information retrieval/search more aware of the context and user interests
Knowledge Discovery in databases is to create a suitable target dataset for data mining
Web log may not be completely reliable Caching – files stored at client but not accessed from server Information pass through the POST method will not be available in a server log
Content preprocessing consists of converting the text, image, scripts and other files such as multimedia into forms that are useful for the web Usage mining process 数据清理： (1) 图片、视频等非用户显式请求的记录，即属性 URI 中后缀名为 gif, jpg, jpeg, ico, rm 等的记录。 (2) 网页的格式信息记录，即属性 URI 中后缀名为 css 的记录。 (3) 属性 Status 中代码显示访问错误的记录， 即属性 Status 中代码值小于 200 或大于 299 的日志记录 ( 属性 Status 中代码为 200~299 通常指示成功响应 ) 。 用户会话识别： (1) 如果 IP 地址不同则认为是不同的用户。 (2) 如果 IP 地址相同，但浏览器软件或操作系统不同，则认为是不同的用户。 (3) 如果 IP 地址相同，浏览器软件和操作系统也相同，那么根据引用信息进行进一步判断。 检查记录的属性 ReferURI ，如果 ReferURI 中记录的 URL 没有被访问过，则认为该记录为一个新的用户会话；或如果 ReferURI 为空，且该记录与上一条记录的访问时间间隔大于 10 s ，也认为该记录为一个新的用户会话。 (4) 根据前 3 条规则得到的每个用户会话可能包含了用户在不同时间的多次访问，因此，采用基于页面访问时间的方法进一步进行用户会话识别，得到用户会话集合。 路径补充： 路径补充是通过分析将日志中没有记录的信息补充完整，得到用户实际的浏览路径。本文采用基于引用的分析方法完成路径补充。
Ambiguity : the level at which clicksare analyzed ( URL A, B, or C as basic identifier) is very shallow, almost no meaning – Dynamic URLs: meaningless URLs even more ambiguity – Semantic Web Usage Mining: (Oberleet al., 2003) • Scalability : Massive Web Log data that cannot fit in main memory requires techniques that are scalable (stream data mining) (Nasraouiet al.: WebKDD2003, ICDM 2003) • Handling Evolution : Usage data that changes with time – Mining & Validation in dynamic environments: largely unexplored area…except in: (Mitchell et al. 1994; Widmer, 1996; Maloof& Michalski, 2000) – In the Web usage domain:(Desikan& Srivastava, 2004; Nasraouiet al.: WebKDD2003, ICDM 2003, KDD 2005, Computer Networks 2006, CIKM 2006) • From Clicks to Concepts : few efforts exist based on laborious manual construction of concepts, website ontology or taxonomy – How to do this automatically? (Berendtet al., 2002; Oberleet al., 2003; Dai & Mobasher, 2002; Eirinakiet al., 2003) • Implementing recommender systems can be slow, costly and a bottle neck especially – for researchers who need to perform tests on a variety of websites – For website owners that cannot afford expensive or complicated solutions
1 。时间阈值 Time out 来划分不同的用户会话；改进的会话识别，动态的 Time out 划分；统计学特征、滑动窗口 模式发现： 1 。 统计分析 2 。序列模式 Markov 模型 3 。关联规则 最大前向引用 (Maximal Forward Reference, 简称 MFR) Ap riori 算法 4 。分类和聚类 决策树、分类法、贝叶斯分类法
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