基于用户模糊聚类的两阶段协同过滤推荐

推荐系统中,随着用户数目和商品数目的日益增加,传统的协同过滤技术在生成推荐时的速度已经成为一种瓶颈。针对此问题,本文提出了一种基于用户模糊聚类的两阶段协同过滤推荐。两阶段分为离线和在线两个阶段。离线时,应用模糊聚类技术,对基本用户进行模糊聚类;在线时,利用已有的用户模糊聚类寻找目标用户的最近邻居,并产生推荐。实验表明,基于用户模糊聚类的两阶段协同过滤推荐不仅加快了推荐生成速度,还提高了推荐质量。     

基于模糊聚类的协同过滤推荐方法

推荐系统是利用用户的历史偏好信息实现个性化服务的系统,它已经成为电子商务和信息获取领域中的重要应用。文中提出了一种通过模糊聚类的方法将项目属性特征的相似性与基于项目的协同过滤推荐技术相结合的推荐方法,首先应用模糊聚类技术对项目聚类,得到项目在属性特征上的相似关系群,然后与用户一项目评分矩阵中的协同相似关系群组合得到综合相似关系群,最后,利用综合相似关系群为目标用户推荐项目。实验结果表明,该方法不仅可有效改善基于项目的协同过滤推荐算法面临的“冷启动”问题,而且确实提高了推荐系统的推荐精度。     

个性化服务中基于用户聚类的协同过滤推荐

协同过滤技术被成功地应用于个性化推荐系统中，但随着系统规模扩大，它的效能逐渐降低。针对此缺点，使用了基于用户聚类的协同过滤推荐，根据用户评分的相似性对用户聚类，在此基础上搜索目标用户的最近邻居，从而缩小用户的搜索范围。本文还提出将协同过滤推荐分为类内相似系数计算和产生推荐两个阶段，把相似系数的计算放在离线部分，减少在线推荐的计算量，提高实时响应速度。另对聚类算法初始聚类中心的选取也做了改进。     

基于项目聚类的协同过滤推荐算法

推荐系统是电子商务中最重要的技术之一 ,协同过滤是推荐系统中采用最为广泛也是最成功的推荐技术 .随着电子商务系统用户数目和商品数目日益增加 ,在整个用户空间上寻找目标用户的最近邻居非常耗时 ,导致推荐系统的实时性要求难以保证 .针对上述问题 ,本文提出了一种基于项目聚类的协同过滤推荐算法 ,根据用户对项目评分的相似性对项目进行聚类 ,生成相应的聚类中心 ,在此基础上计算目标项目与聚类中心的相似性 ,从而只需要在与目标项目最相似的若干个聚类中就能寻找到目标项目的大部分最近邻居并产生推荐列表 .实验结果表明 ,本算法可以有效提高推荐系统的实时响应速度     

基于用户兴趣分类的协同过滤推荐算法

在现代信息网络中,个性化的推荐系统已经成为用户和应用软件交互的关键部分.推荐算法是个性化推荐系统的核心,其中,协同过滤算法是至今应用最为成功的推荐算法之一.但传统的协同过滤算法没有考虑用户兴趣的多样性,对用户兴趣度量不准确,难以适用于用户多兴趣的推荐系统,提出了适应用户兴趣多样性的协同过滤算法并利用改进的模糊聚类算法搜...     

基于用户聚类的协同过滤推荐方法

为了提高电子商务网站的个性化服务效率,给出了一种改进的用户聚类的协同过滤推荐方法,该算法利用用户对项目的关注的相似性来修正原始相似性计算,综合考虑用户对项目的关注和用户评价对推荐的影响.实验表明,该基于用户聚类的协同过滤推荐算法不仅减少了用户在寻找最近邻居的搜索强度,加快了推荐生成速度,而且增强了推荐算法的实时性,提高了推荐质量.     

基于用户模糊聚类的个性化推荐算法

针对目前协同过滤算法中存在的项目相似性计算不准确问题,提出运用模糊聚类技术对用户进行聚类,将单个用户对项目的评分转化为用户相似群体对项目的评分,构造密集的用户模糊簇-项目的评分矩阵,并结合项目自身的类别属性特征对相似性计算的影响最终完成项目相似性的计算,以提高项目相似性计算的准确度,实验结果表明,可提高协同过滤推荐算法的推荐精度.     

基于密度的动态协同过滤图书推荐算法*

针对协同过滤推荐技术在个性化服务应用中存在的服务质量和服务效率问题,提出一种基于密度的动态协同过滤图书推荐算法。在对读者的图书流通记录进行兴趣度模糊筛选基础上,利用扩展的密度聚类算法进行区域聚类,读者的兴趣模型依据聚类区域的密度与权重变化更新,动态进行协同过滤图书推荐。实验表明,该算法在提高推荐精确度上,优于传统的协同过滤推荐算法。     

基于项目属性的用户聚类协同过滤推荐算法

协同过滤推荐算法是个性化推荐服务系统的关键技术,由于项目空间上用户评分数据的极端稀疏性,传统推荐系统中的用户相似度量算法开销较大并且无法保证项目推荐精度.通过对共同感兴趣的项目属性的相似用户进行聚类,构建了不同项目评价的用户相似性,设计了一种优化的协同过滤推荐算法.实验结果表明,该算法能够有效避免由于数据稀疏性带来的弊端,提高了系统的推荐质量.     

一种基于情景的协同过滤推荐算法

针对协同过滤推荐算法中数据极端稀疏所带来的推荐精度低下的问题,文中提出一种基于情景的协同过滤推荐算法。通过引入项目情景相似度的概念,基于项目情景相似度改进了用户之间相似度的计算公式,并将此方法应用至用户离线聚类过程中,最终利用用户聚类矩阵和用户评分数据产生在线推荐。实验结果表明,该算法能够在数据稀疏的情况下定位目标用户的最近邻,一定程度上缓解数据极端稀疏性引起的问题,并减少系统在线推荐的时间。     

个性化推荐算法设计

协同过滤技术（collaborative filtering）目前被成功地应用于个性化推荐系统中，但随着系统规模的扩大，它的效能逐渐降低，提出了一种高效的个性化推荐算法，它包括维数简化和项集相似性计算两个过程，这种算法在提高精确性的基础上减少了计算耗费，可以较好地解决应用协同过滤技术的推荐系统所存在的稀疏性，扩展性等问题，快速产生精确的个性化推荐结果。     

Automatic metadata expansion and indirect collaborative filtering for TV program recommendation system

TV Program recommendation is a good example of a novel application of networked appliances using personalization technologies. The aim of this paper is to propose methods to improve the accuracy of TV program recommendation. Automatic metadata expansion (AME) is a method to enhance TV program metadata from electronic program guide (EPG) data, and indirect collaborative filtering (ICF) is a method to recommend non-persistent items such as TV programs based on the preferences of other members in a community. In this paper, the effectiveness of these methods is confirmed through experiments. This online TV recommendation system is currently being used by 230,000 members in Japan. The result of the actual operation is also discussed.     

Web personalization: is it effective?

By knowing their customers' needs better, firms can offer products and services at the right price, in the right context, and at the right time. Web personalization enables this sort of interaction. Firms can implement personalization by integrating independent packages such as data mining and collaborative filtering tools with the Web server; or personalization could take the form of a package solution. In general, Web personalization serves three main objectives: It draws attention to a company and its products and services; implants messages; and attempts to persuade. The study presented provides empirical support that Web personalization can motivate users to consider agent-recommended items.     

A hybrid collaborative filtering method for multiple-interests and multiple-content recommendation in E-Commerce

Recommender systems apply knowledge discovery techniques to the problem of making personalized recommendations for products or services during a live interaction. These systems, especially collaborative filtering based on user, are achieving widespread success on the Web. The tremendous growth in the amount of available information and the kinds of commodity to Web sites in recent years poses some key challenges for recommender systems. One of these challenges is ability of recommender systems to be adaptive to environment where users have many completely different interests or items have completely different content (We called it as Multiple interests and Multiple-content problem). Unfortunately, the traditional collaborative filtering systems can not make accurate recommendation for the two cases because the predicted item for active user is not consist with the common interests of his neighbor users. To address this issue we have explored a hybrid collaborative filtering method, collaborative filtering based on item and user techniques, by combining collaborative filtering based on item and collaborative filtering based on user together. Collaborative filtering based on item and user analyze the user-item matrix to identify similarity of target item to other items, generate similar items of target item, and determine neighbor users of active user for target item according to similarity of other users to active user based on similar items of target item.In this paper we firstly analyze limitation of collaborative filtering based on user and collaborative filtering based on item algorithms respectively and emphatically make explain why collaborative filtering based on user is not adaptive to Multiple-interests and Multiple-content recommendation. Based on analysis, we present collaborative filtering based on item and user for Multiple-interests and Multiple-content recommendation. Finally, we experimentally evaluate the results and compare them with collaborative filtering based on user and collaborative filtering based on item, respectively. The experiments suggest that collaborative filtering based on item and user provide better recommendation quality than collaborative filtering based on user and collaborative filtering based on item dramatically.     

User attitudes towards news content personalization

Personalizing news content requires to choose the appropriate depth of personalization and to assess the extent to which readers’ explicit expressions of interest in general and specific news topics can be used as the basis for personalization. A preliminary survey examined 117 respondents’ attitudes towards news content personalization and their interest in various news topics and subtopics. The second survey examined 23 participants’ declared and actual interests. Participants preferred personalization based on general news topics. Declared interest in general news topics adequately predicted the actual interests in some topics, while in others users’ interests differed between general news topics and subtopics. The variance in interest in items also differed among topics. Thus, different personalization methods should be used for different topics. For some, such as ‘Sports’, users show either high interest or no interest at all. In the latter case most articles related to the topic should be removed, with the exception of items that refer to unique events that may raise general interest according to the expressed interest. In other topics, such as ‘Science & Technology’, most users are interested in important articles, even if they are not interested in the general news topic. Here, the filtering technique should identify the important articles and present them to all readers. The results can be used to develop effective and simple personalization mechanisms which can be applied to the personalization of news, as well as to other domains.     

融合注意力机制的深度协同过滤推荐算法

传统基于项目的协同过滤算法在计算项目之间相似度时只考虑历史项目的评分，而忽略了历史项目偏好对其的影响，以至于推荐精度不够理想。针对此问题，提出了一种融合注意力机制的深度电影推荐算法。根据得到的隐性反馈，在特征级注意力框架上，从项目内容特征提取网络开始，学习项目特征的偏好；将项目特征偏好与项目特征加权得到项目内容特征向量；在项目级特征注意力框架中，通过项目内容特征向量学习对项目偏好的评分，从而产生最终的推荐结果。实验结果表明，提出的推荐算法在MovieLens 100K和MovieLens 1M两个公开数据集上的准确率和推荐个性化较传统算法均有不同程度的提高，表现出较为优越的推荐性能。     

基于项目分层的个性化推荐方法

协同过滤目前较为成功地应用于个性化推荐系统中.但随着系统规模的扩大和待推荐项目的不断增加,协同过滤面临着稀疏性问题和新项目推荐问题,制约了推荐效果.在此分析了传统协同过滤推荐方法中存在的问题,提出一种基于项目分层的个性化推荐方法.采用了基于多层兴趣表示的用户相似性算法,并结合相似用户推荐项与项目相似性来推荐新项目.该推荐方法在稀疏数据集上能表现出较好的推荐质量,同时也能够有效地解决新项目推荐问题.     

基于搜索结果的个性化推荐系统研究

搜索引擎返回的信息太多且不能根据用户的兴趣提供检索结果,使得用户使用搜索引擎难以用简便的方式找到感兴趣的文档。个性化推荐是一种旨在减轻用户在信息检索方面负担的有效方法。文中把内容过滤技术和文档聚类技术相结合,实现了一个基于搜索结果的个性化推荐系统,以聚类的方法自动组织搜索结果,主动推荐用户感兴趣的文档。通过建立用户概率兴趣模型,对搜索结果STC聚类的基础上进行内容过滤。实验表明,概率模型比矢量空间模型更好地表达了用户的兴趣和变化。     

Case-studies on exploiting explicit customer requirements in recommender systems

Recommender Systems (RS) suggest useful and interesting items to users in order to increase user satisfaction and online conversion rates. They typically exploit explicit or implicit user feedback such as ratings, buying records or clickstream data and apply statistical methods to derive recommendations. This paper focuses on explicitly formulated customer requirements as the sole type of user feedback. Its contribution lies in comparing different techniques such as knowledge- and utility-based methods, collaborative filtering, association rule mining as well as hybrid variants when user models consist solely of explicit customer requirements. We examine how this type of user feedback can be exploited for personalization in e-commerce scenarios. Furthermore, examples of actual online shops are developed where such contextual user information is available, demonstrating how more efficient RS configurations can be implemented. Results indicate that, especially for new users, explicit customer requirements are a useful source of feedback for personalization and hybrid configurations of collaborative and knowledge-based techniques achieve best results.