2,636 research outputs found

    A Novel Keyword Suggestion Method to Achieve Competitive Advertising on Search Engines

    Get PDF
    Search engine advertising is a popular business model for online advertising and recently a new strategy (i.e. competitive advertising) is emerging. Competitive advertising is helpful for organizations to expand market shares from competitors, which is crucial to sustain competitive advantage. To achieve the goal of competitive advertising, appropriate and fruitful competitive keywords should be provided to advertisers. However, existing keywords suggestion methods usually recommend general business keywords based on co-occurrence analysis. They not only fail to enable competitive advertising, but also limit advertisers to a small number of hot keywords, causing high bidding costs. As a response, this study proposes a competitive keywords suggestion method based on query logs. It uses the indirect associations between keywords and the hidden topic information captured by query logs to recommend competitive keywords. Through the method, massive competitive keywords are mined out to help organizations achieve competitive advertising and simultaneously broaden the choices of keywords for search engine advertising. Experiments are conducted to demonstrate that the proposed method could have a good performance than other methods, proving that it can help organizations well achieve the goal of competitive advertising

    Preference Learning

    Get PDF
    This report documents the program and the outcomes of Dagstuhl Seminar 14101 “Preference Learning”. Preferences have recently received considerable attention in disciplines such as machine learning, knowledge discovery, information retrieval, statistics, social choice theory, multiple criteria decision making, decision under risk and uncertainty, operations research, and others. The motivation for this seminar was to showcase recent progress in these different areas with the goal of working towards a common basis of understanding, which should help to facilitate future synergies

    CHORUS Deliverable 2.1: State of the Art on Multimedia Search Engines

    Get PDF
    Based on the information provided by European projects and national initiatives related to multimedia search as well as domains experts that participated in the CHORUS Think-thanks and workshops, this document reports on the state of the art related to multimedia content search from, a technical, and socio-economic perspective. The technical perspective includes an up to date view on content based indexing and retrieval technologies, multimedia search in the context of mobile devices and peer-to-peer networks, and an overview of current evaluation and benchmark inititiatives to measure the performance of multimedia search engines. From a socio-economic perspective we inventorize the impact and legal consequences of these technical advances and point out future directions of research

    Learning domain-specific sentiment lexicons with applications to recommender systems

    Get PDF
    Search is now going beyond looking for factual information, and people wish to search for the opinions of others to help them in their own decision-making. Sentiment expressions or opinion expressions are used by users to express their opinion and embody important pieces of information, particularly in online commerce. The main problem that the present dissertation addresses is how to model text to find meaningful words that express a sentiment. In this context, I investigate the viability of automatically generating a sentiment lexicon for opinion retrieval and sentiment classification applications. For this research objective we propose to capture sentiment words that are derived from online users’ reviews. In this approach, we tackle a major challenge in sentiment analysis which is the detection of words that express subjective preference and domain-specific sentiment words such as jargon. To this aim we present a fully generative method that automatically learns a domain-specific lexicon and is fully independent of external sources. Sentiment lexicons can be applied in a broad set of applications, however popular recommendation algorithms have somehow been disconnected from sentiment analysis. Therefore, we present a study that explores the viability of applying sentiment analysis techniques to infer ratings in a recommendation algorithm. Furthermore, entities’ reputation is intrinsically associated with sentiment words that have a positive or negative relation with those entities. Hence, is provided a study that observes the viability of using a domain-specific lexicon to compute entities reputation. Finally, a recommendation system algorithm is improved with the use of sentiment-based ratings and entities reputation

    Enterprise Search in the European Union: A Techno-economic Analysis

    Get PDF
    This Report contributes to the work being carried out by IPTS on the potential of Search, discussing, in particular, the prospects of Enterprise search as well as the main challenges and opportunities. It is part of CHORUS+, an initiative supported by the Directorate General Information Society and Media. Information about CHORUS+ is available at http://avmediasearch.euJRC.J.3-Information Societ

    Supporting interactive summarization for explainable exploratory search

    Get PDF
    Exploratory search is characterised by user uncertainty with respect to search domain and information seeking goals. This uncertainty can negatively impact users’ abilities to assess the quality of search results, causing them to scroll through more documents than necessary and struggle to give consistent relevance feedback. As users’ information needs are assumed to be highly dynamic and expected to evolve over time, successful searches can be indistinguishable from those that have drifted erroneously away from their original search intent. Indeed, given their lack of domain knowledge, searchers may be slow, or even unable, to recognise when search results have become skewed towards another topic. With these issues in mind, we designed and implemented an interactive search system which integrated a keyword summaries algorithm, Exploratory Search Captions (ESC) to support users in exploratory search. This thesis investigated into the usefulness of ESC in terms of user experience, user behaviour and also explored impact of design decision in terms of user satisfaction. We evaluated the ESC system with a user study in the context of exploratory search of scientific literature in Computer Science. According to the user study results, participants almost unanimously preferred the retrieval system that incorporated ESC; and the presence of captions dramatically impacts user behaviour: users issue more queries, investigate fewer documents per query, but see more documents overall. We demonstrated the usefulness of ESC, the improved usability of ESC system, and the positive impact of our design decisions

    Multi modal multi-semantic image retrieval

    Get PDF
    PhDThe rapid growth in the volume of visual information, e.g. image, and video can overwhelm users’ ability to find and access the specific visual information of interest to them. In recent years, ontology knowledge-based (KB) image information retrieval techniques have been adopted into in order to attempt to extract knowledge from these images, enhancing the retrieval performance. A KB framework is presented to promote semi-automatic annotation and semantic image retrieval using multimodal cues (visual features and text captions). In addition, a hierarchical structure for the KB allows metadata to be shared that supports multi-semantics (polysemy) for concepts. The framework builds up an effective knowledge base pertaining to a domain specific image collection, e.g. sports, and is able to disambiguate and assign high level semantics to ‘unannotated’ images. Local feature analysis of visual content, namely using Scale Invariant Feature Transform (SIFT) descriptors, have been deployed in the ‘Bag of Visual Words’ model (BVW) as an effective method to represent visual content information and to enhance its classification and retrieval. Local features are more useful than global features, e.g. colour, shape or texture, as they are invariant to image scale, orientation and camera angle. An innovative approach is proposed for the representation, annotation and retrieval of visual content using a hybrid technique based upon the use of an unstructured visual word and upon a (structured) hierarchical ontology KB model. The structural model facilitates the disambiguation of unstructured visual words and a more effective classification of visual content, compared to a vector space model, through exploiting local conceptual structures and their relationships. The key contributions of this framework in using local features for image representation include: first, a method to generate visual words using the semantic local adaptive clustering (SLAC) algorithm which takes term weight and spatial locations of keypoints into account. Consequently, the semantic information is preserved. Second a technique is used to detect the domain specific ‘non-informative visual words’ which are ineffective at representing the content of visual data and degrade its categorisation ability. Third, a method to combine an ontology model with xi a visual word model to resolve synonym (visual heterogeneity) and polysemy problems, is proposed. The experimental results show that this approach can discover semantically meaningful visual content descriptions and recognise specific events, e.g., sports events, depicted in images efficiently. Since discovering the semantics of an image is an extremely challenging problem, one promising approach to enhance visual content interpretation is to use any associated textual information that accompanies an image, as a cue to predict the meaning of an image, by transforming this textual information into a structured annotation for an image e.g. using XML, RDF, OWL or MPEG-7. Although, text and image are distinct types of information representation and modality, there are some strong, invariant, implicit, connections between images and any accompanying text information. Semantic analysis of image captions can be used by image retrieval systems to retrieve selected images more precisely. To do this, a Natural Language Processing (NLP) is exploited firstly in order to extract concepts from image captions. Next, an ontology-based knowledge model is deployed in order to resolve natural language ambiguities. To deal with the accompanying text information, two methods to extract knowledge from textual information have been proposed. First, metadata can be extracted automatically from text captions and restructured with respect to a semantic model. Second, the use of LSI in relation to a domain-specific ontology-based knowledge model enables the combined framework to tolerate ambiguities and variations (incompleteness) of metadata. The use of the ontology-based knowledge model allows the system to find indirectly relevant concepts in image captions and thus leverage these to represent the semantics of images at a higher level. Experimental results show that the proposed framework significantly enhances image retrieval and leads to narrowing of the semantic gap between lower level machinederived and higher level human-understandable conceptualisation

    Dataset search: a survey

    Get PDF
    Generating value from data requires the ability to find, access and make sense of datasets. There are many efforts underway to encourage data sharing and reuse, from scientific publishers asking authors to submit data alongside manuscripts to data marketplaces, open data portals and data communities. Google recently beta released a search service for datasets, which allows users to discover data stored in various online repositories via keyword queries. These developments foreshadow an emerging research field around dataset search or retrieval that broadly encompasses frameworks, methods and tools that help match a user data need against a collection of datasets. Here, we survey the state of the art of research and commercial systems in dataset retrieval. We identify what makes dataset search a research field in its own right, with unique challenges and methods and highlight open problems. We look at approaches and implementations from related areas dataset search is drawing upon, including information retrieval, databases, entity-centric and tabular search in order to identify possible paths to resolve these open problems as well as immediate next steps that will take the field forward.Comment: 20 pages, 153 reference
    corecore