Community Question Answering (CQA) websites, where people share expertise on open platforms, have become large repositories of valuable knowledge. To bring the best value out of these knowledge repositories, it is critically important for CQA services to know how to find the right experts, retrieve archived similar questions and recommend best answers to new questions. To tackle this cluster of closely related problems in a principled approach, we proposed Topic Expertise Model (TEM), a novel probabilistic generative model with GMM hybrid, to jointly model topics and expertise by integrating textual content model and link structure analysis. Based on TEM results, we proposed CQARank to measure user interests and expertise score under different topics. Leveraging the question answering history based on long-term community reviews and voting, our method could find experts with both similar topical preference and high topical expertise. Experiments carried out on Stack Overflow data, the largest CQA focused on computer programming, show that our method achieves significant improvement over existing methods on multiple metrics.

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CQArank: jointly model topics and expertise in community question answering

Crowdsourcing information systems are socio-technical systems that provide informational products or services by harnessing the diverse potential of large groups of people via the Web. Interested individuals can contribute to such systems by selecting among a wide range of open tasks. Arguing that current approaches are suboptimal in terms of matching tasks and contributors' individual interests and capabilities, this article advocates the introduction of personalized task recommendation mechanisms. We contribute to a conceptual foundation for the design of such mechanisms by conducting a systematic review of the corresponding academic literature. Based on the insights derived from this analysis, we identify a number of issues for future research. In particular, our findings highlight the need for more significant empirical results through large-scale online experiments, an improved dialog with mainstream recommender systems research, and the integration of various sources of knowledge that exceed the boundaries of individual systems.

Personalized task recommendation in crowdsourcing information systems - Current state of the art

Community Question Answering (CQA) websites provide a rapidly growing source of information in many areas. This rapid growth, while offering new opportunities, puts forward new challenges. In most CQA implementations there is little effort in directing new questions to the right group of experts. This means that experts are not provided with questions matching their expertise, and therefore new matching questions may be missed and not receive a proper answer. We focus on finding experts for a newly posted question. We investigate the suitability of two statistical topic models for solving this issue and compare these methods against more traditional Information Retrieval approaches. We show that for a dataset constructed from the Stackoverflow website, these topic models outperform other methods in retrieving a candidate set of best experts for a question. We also show that the Segmented Topic Model gives consistently better performance compared to the Latent Dirichlet Allocation Model.

https://web.cs.dal.ca/~eem/res/pubs/pubs/2012-Riahi-WWW.pdf

Finding expert users in community question answering

A system for identifying influential users of a social network platform The system may compute a score for each of multiple users Such a score may be topic-based, leading to a more accurate identification of influential users Such a topic-based score may indicate authority and/or impact of a user with respect to a topic The impact may be computed based on authority combined with other factors, such as power of the user The authority score may be simply computed, in whole or in part, directly from a tweet log without, for example creating a retweet graph As a result, the scores may be computed, using MapReduce primitives or other constructs that allow the computations to be distributed across multiple parallel processors Such scores may be used to select users based on impact as part of social trend analysis, marketing or other functions

Social media impact assessment

Community Question Answering (CQA) service provides a platform for increasing number of users to ask and answer for their own needs but unanswered questions still exist within a fixed period. To address this, the paper aims to route questions to the right answerers who have a top rank in accordance of their previous answering performance. In order to rank the answerers, we propose a framework called Question Routing (QR) which consists of four phases: (1) performance profiling, (2) expertise estimation, (3) availability estimation, and (4) answerer ranking. Applying the framework, we conduct experiments with Yahoo! Answers dataset and the results demonstrate that on average each of 1,713 testing questions obtains at least one answer if it is routed to the top 20 ranked answerers.

http://www.cse.cuhk.edu.hk/~king/PUB/CIKM2010-Li-p1585.pdf

Routing questions to appropriate answerers in community question answering services

User-Interactive Question Answering (QA) communities such as Yahoo! Answers are growing in popularity. However, as these QA sites always have thousands of new questions posted daily, it is difficult for users to find the questions that are of interest to them. Consequently, this may delay the answering of the new questions. This gives rise to question recommendation techniques that help users locate interesting questions. In this paper, we adopt the Probabilistic Latent Semantic Analysis (PLSA) model for question recommendation and propose a novel metric to evaluate the performance of our approach. The experimental results show our recommendation approach is effective.

/pdf/probabilistic-question-recommendation-for-question-answering-9zvvx4ps21.pdf

Probabilistic question recommendation for question answering communities

Social annotations on a Web document are highly generalized description of topics contained in that page. Their tagged frequency indicates the user attentions with various degrees. This makes annotations a good resource for summarizing multiple topics in a Web page. In this paper, we present a tag-oriented Web document summarization approach by using both document content and the tags annotated on that document. To improve summarization performance, a new tag ranking algorithm named EigenTag is proposed in this paper to reduce noise in tags. Meanwhile, association mining technique is employed to expand tag set to tackle the sparsity problem. Experimental results show our tag-oriented summarization has a significant improvement over those not using tags.

/pdf/tag-oriented-document-summarization-3qi3wml158.pdf

Tag-oriented document summarization

This paper proposes an efficient relevance feedback based interactive model for keyword generation in sponsored search advertising. We formulate the ranking of relevant terms as a supervised learning problem and suggest new terms for the seed by leveraging user relevance feedback information. Active learning is employed to select the most informative samples from a set of candidate terms for user labeling. Experiments show our approach improves the relevance of generated terms significantly with little user effort required.

/pdf/advertising-keyword-generation-using-active-learning-4376yzqnhv.pdf

Advertising keyword generation using active learning

The invention discloses a recommended method for analyzing the latent semantic problem based on the probability. The method describes the interest of a user through a state model in the latent semantic analysis on the probability and provides the compatible problem recommendation for the user interactive type question-answering system. The method adopts a ternary state model, has the advantages of two recommended ways based on the content and collaborative filtering, performs problem recommendation according to the personalized information of the user, and has high accuracy and good applicability in the user interactive type question-answering system.

Method for recommending problem based on probability latent semantic analysis

Online advertising has now turned to be one of the major revenue sources for today's Internet companies. Among the different channels of advertising, contextual advertising takes the great part. There are already lots of studies done for the keyword extraction problem in contextual advertising for English, however, little has been conducted for Chinese, which is mainly different from English linguistically. In this paper, we focus on the problem of Chinese advertising keywords extraction and propose a novel approach based on the idea of classification. We adopt C4.5 as the classifier model and select appropriate features with Chinese linguistic characteristic taken into consideration. The experimental results indicate that our approach is promising.

Mingcheng Qu

Papers

Probabilistic question recommendation for question answering communities

Tag-oriented document summarization

Advertising keyword generation using active learning

Method for recommending problem based on probability latent semantic analysis

A Novel Approach to Keyword Extraction for Contextual Advertising