Reiner Kraft

Searching with context

Contextual search refers to proactively capturing the information need of a user by automatically augmenting the user query with information extracted from the search context; for example, by using terms from the web page the user is currently browsing or a file the user is currently editing.We present three different algorithms to implement contextual search for the Web. The first, it query rewriting (QR), augments each query with appropriate terms from the search context and uses an off-the-shelf web search engine to answer this augmented query. The second, rank-biasing (RB), generates a representation of the context and answers queries using a custom-built search engine that exploits this representation. The third, iterative filtering meta-search (IFM), generates multiple subqueries based on the user query and appropriate terms from the search context, uses an off-the-shelf search engine to answer these subqueries, and re-ranks the results of the subqueries using rank aggregation methods.We extensively evaluate the three methods using 200 contexts and over 24,000 human relevance judgments of search results. We show that while QR works surprisingly well, the relevance and recall can be improved using RB and substantially more using IFM. Thus, QR, RB, and IFM represent a cost-effective design spectrum for contextual search.

Y!Q: contextual search at the point of inspiration

Contextual search tries to better capture a users information need by augmenting the users query with contextual information extracted from the search context (for example, terms from the web page the user is currently reading or a file the user is currently editing).This paper presents Y!Q---a first of its kind large-scale contextual search system---and provides an overview of its system design and architecture. Y!Q solves two major problems. First, how to capture high quality search context. Second, how to use that context in a way to improve the relevancy of search queries. To address the first problem, Y!Q introduces an information widget that captures precise search context and provides convenient access to its functionality at the point of inspiration. For example, Y!Q can be easily embedded into web pages using a web API, or it can be integrated into a web browser toolbar. This paper provides an overview of Y!Qs user interaction design, highlighting its novel aspects for capturing high quality search context.To address the second problem, Y!Q uses a semantic network for analyzing search context, possibly resolving ambiguous terms, and generating a contextual digest comprising its key concepts. This digest is passed through a query planner and rewriting framework for augmenting a users search query with relevant context terms to improve the overall search relevancy and experience. We show experimental results comparing contextual Y!Q search results side-by-side with regular Yahoo! web search results. This evaluation suggests that Y!Q results are considered significantly more relevant.The paper also identifies interesting research problems and argues that contextual search may represent the next major step in the evolution of web search engines.

Contextual Ranking of Keywords Using Click Data

The problem of automatically extracting the most interesting and relevant keyword phrases in a document has been studied extensively as it is crucial for a number of applications. These applications include contextual advertising, automatic text summarization, and user-centric entity detection systems. All these applications can potentially benefit from a successful solution as it enables computational efficiency (by decreasing the input size), noise reduction, or overall improved user satisfaction.In this paper, we study this problem and focus on improving the overall quality of user-centric entity detection systems. First, we review our concept extraction technique, which relies on search engine query logs. We then define a new feature space to represent the interestingness of concepts, and describe a new approach to estimate their relevancy for a given context. We utilize click through data obtained from a large scale user-centric entity detection system - Contextual Shortcuts - to train a model to rank the extracted concepts, and evaluate the resulting model extensively again based on their click through data. Our results show that the learned model outperforms the baseline model, which employs similar features but whose weights are tuned carefully based on empirical observations, and reduces the error rate from 30.22% to 18.66%.