Tag Assignment Research Articles

Tagging Multi-Label Categories to Points of Interest From Check-In Data

Category tag of Point Of Interest (POI) serves a crucial role in numerous Location Based Services (LBS) like finding a place of interest, POI recommendation, location-based advertisement, etc. However, it has been found that many POIs (around 30%) do not have any category information. Manual tagging of these categories is a very costly affair as it requires a physical visit to each POI. Hence, an automated method for category tagging of POIs has been identified as an important research problem. The problem of category tagging of POIs is still in its primary stage, requiring further exploration. In this work, we solve the problem in three broad steps i). feature identification, ii). feature extraction, and iii). tag assignment. For the first step, we consider sequential features, temporal features, and spatial features, which can be constructed using check-in data. For the second step, we generate POI embedding representing its features, using a graph-based unsupervised approach. For the final step, the problem is considered a multi-label classification problem. For this, we have used Classifier Chain algorithms which preserves inter-tag correlation. Comparison with state-of-the-art methodologies along with multiple variants of features and classification algorithms show a significant improvement of <inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"><tex-math notation="LaTeX">$5-34\%$</tex-math></inline-formula> by standard metric of average F1-score.

New Probabilistic, Dynamic Multi-Method Ensembles for Optimization Based on the CRO-SL

In this paper, new probabilistic and dynamic (adaptive) strategies for creating multi-method ensembles based on the coral reef optimization with substrate layers (CRO-SL) algorithm are proposed. CRO-SL is an evolutionary-based ensemble approach that is able to combine different search procedures for a single population. In this work, two different probabilistic strategies to improve the algorithm are analyzed. First, the probabilistic CRO-SL (PCRO-SL) is presented, which substitutes the substrates in the CRO-SL population with tags associated with each individual. Each tag represents a different operator which will modify the individual in the reproduction phase. In each generation of the algorithm, the tags are randomly assigned to the individuals with similar probabilities, obtaining this way an ensemble that sees more intense changes with the application of different operators to a given individual than CRO-SL. Second, the dynamic probabilistic CRO-SL (DPCRO-SL) is presented, in which the probability of tag assignment is modified during the evolution of the algorithm, depending on the quality of the solutions generated in each substrate. Thus, the best substrates in the search process will be assigned higher probabilities than those which showed worse performance during the search. The performances of the proposed probabilistic and dynamic ensembles were tested for different optimization problems, including benchmark functions and a real application of wind-turbine-layout optimization, comparing the results obtained with those of existing algorithms in the literature.

Party Positions from Wikipedia Classifications of Party Ideology

AbstractWe develop a new measure of party position based on a scaling of ideology tags supplied in infoboxes on political parties’ Wikipedia pages. Assuming a simple model of tag assignment, we estimate the locations of parties and ideologies in a common space. We find that the recovered scale can be interpreted in familiar terms of “left versus right.” Estimated party positions correlate well with ratings of parties’ positions from extant large-scale expert surveys, most strongly with ratings of general left–right ideology. Party position estimates also show high stability in a test–retest scenario. Our results demonstrate that a Wikipedia-based approach yields valid and reliable left–right scores comparable to scores obtained via conventional expert coding methods. It thus provides a measure with potentially unlimited party coverage. Our measurement strategy is also applicable beyond Wikipedia.

Extracting Time Expressions and Named Entities with Constituent-Based Tagging Schemes

Time expressions and named entities play important roles in data mining, information retrieval, and natural language processing. However, the conventional position-based tagging schemes (e.g., the BIO and BILOU schemes) that previous research used to model time expressions and named entities suffer from the problem of inconsistent tag assignment. To overcome the problem of inconsistent tag assignment, we designed a new type of tagging schemes to model time expressions and named entities based on their constituents. Specifically, to model time expressions, we defined a constituent-based tagging scheme termed TOMN scheme with four tags, namely T, O, M, and N, indicating the defined constituents of time expressions, namely time token, modifier, numeral, and the words outside time expressions. To model named entities, we defined a constituent-based tagging scheme termed UGTO scheme with four tags, namely U, G, T, and O, indicating the defined constituents of named entities, namely uncommon word, general modifier, trigger word, and the words outside named entities. In modeling, our TOMN and UGTO schemes model time expressions and named entities under conditional random fields with minimal features according to an in-depth analysis for the characteristics of time expressions and named entities. Experiments on diverse datasets demonstrate that our proposed methods perform equally with or more effectively than representative state-of-the-art methods on both time expression extraction and named entity extraction.

Enhancing the Quality of Image Tagging Using a Visio-Textual Knowledge Base

Auto-tagging of images is important for image understanding and for tag-based applications viz. image retrieval, visual question-answering, image captioning, etc. Although existing tagging methods incorporate both visual and textual information to assign/refine tags, they lag in tag-image relevance, completeness, and preciseness, thereby resulting in the unsatisfactory performance of tag-based applications. In order to bridge this gap, we propose a novel framework for tag assignment using knowledge embedding (TAKE) from a proposed external knowledge base, considering properties such as Rarity, Newness, Generality, and Naturalness ( RNGN properties). These properties help in providing a rich semantic representation to images. Existing knowledge bases provide multiple types of relations extracted through only one modality, either text or visual, which is not effective in image related applications. We construct a simple yet effective Visio-Textual Knowledge Base (VTKB) with only four relations using reliable resources such as Wikipedia, thesauruses, dictionaries, etc. Our large scale experiments demonstrate that the proposed combination of TAKE and VTKB assigns a large number of high quality tags in comparison to the ConceptNet and ImageNet knowledge bases when used in conjunction with TAKE. Also, the effectiveness of knowledge embedding through VTKB is evaluated for image tagging and tag-based image retrieval (TBIR).

Time and ontology for resource recommendation system

Nowadays social tagging systems have considerable growth. These systems help users to find their favorite resources among the large volume of information. Many ways have been proposed for recommending. Since the tags are connotations of users’ interests and also the time of assigning tags indicates the current interests of users, so the combination of semantic influence of tags and time of tag assignment information can effect on the accuracy of recommendations. In this paper, an item recommendation system is proposed that by using important available information in tagging systems, e.g. time, and also using available ontology, the accuracy of recommended results has been improved. The evaluation of the proposed system is performed on movielens.org dataset. The results in comparing with other methods demonstrated the improving quality of the proposed system.

Deep Collaborative Embedding for Social Image Understanding.

In this work, we investigate the problem of learning knowledge from the massive community-contributed images with rich weakly-supervised context information, which can benefit multiple image understanding tasks simultaneously, such as social image tag refinement and assignment, content-based image retrieval, tag-based image retrieval and tag expansion. Towards this end, we propose a Deep Collaborative Embedding (DCE) model to uncover a unified latent space for images and tags. The proposed method incorporates the end-to-end learning and collaborative factor analysis in one unified framework for the optimal compatibility of representation learning and latent space discovery. A nonnegative and discrete refined tagging matrix is learned to guide the end-to-end learning. To collaboratively explore the rich context information of social images, the proposed method integrates the weakly-supervised image-tag correlation, image correlation and tag correlation simultaneously and seamlessly. The proposed model is also extended to embed new tags in the uncovered space. To verify the effectiveness of the proposed method, extensive experiments are conducted on two widely-used social image benchmarks for multiple social image understanding tasks. The encouraging performance of the proposed method over the state-of-the-art approaches demonstrates its superiority.

CNN-feature based automatic image annotation method

Automatic image annotation(AIA) methods are considered as a kind of efficient schemes to solve the problem of semantic-gap between the original images and their semantic information. However, traditional annotation models work well only with finely crafted manual features. To address this problem, we combined the CNN feature of an image into our proposed model which we referred as SEM by using a famous CNN model-AlexNet. We extracted a CNN feature by removing its final layer and it is proved to be useful in our SEM model. Additionally, based on the experience of the traditional KNN models, we propose a model to address the problem of simultaneously addressing the image tag refinement and assignment while maintaining the simplicity of the KNN model. The proposed model divides the images which have similar features into a semantic neighbor group. Moreover, utilizing a self-defined Bayesian-based model, we distribute the tags which belong to the neighbor group to the test images according to the distance between the test image and the neighbors. At last, the experiments are performed on three typical image datasets corel5k, espGame and laprtc12, which verify the effectiveness of the proposed model.

Weakly-Supervised Deep Nonnegative Low-Rank Model for Social Image Tag Refinement and Assignment

It has been well known that the user-provided tags of social images are imperfect, i.e., there exist noisy, irrelevant or incomplete tags. It heavily degrades the performance of many multimedia tasks. To alleviate this problem, we propose a Weakly-supervised Deep Nonnegative Low-rank model (WDNL) to improve the quality of tags by integrating the low-rank model with deep feature learning. A nonnegative low-rank model is introduced to uncover the intrinsic relationships between images and tags by simultaneously removing noisy or irrelevant tags and complementing missing tags. The deep architecture is leveraged to seamlessly connect the visual content and the semantic tag. That is, the proposed model can well handle the scalability by assigning tags to new images. Extensive experiments conducted on two real-world datasets demonstrate the effectiveness of the proposed method compared with some state-of-the-art methods.

Weakly Supervised Deep Matrix Factorization for Social Image Understanding.

The number of images associated with weakly supervised user-provided tags has increased dramatically in recent years. User-provided tags are incomplete, subjective and noisy. In this paper, we focus on the problem of social image understanding, i.e., tag refinement, tag assignment, and image retrieval. Different from previous work, we propose a novel weakly supervised deep matrix factorization algorithm, which uncovers the latent image representations and tag representations embedded in the latent subspace by collaboratively exploring the weakly supervised tagging information, the visual structure, and the semantic structure. Due to the well-known semantic gap, the hidden representations of images are learned by a hierarchical model, which are progressively transformed from the visual feature space. It can naturally embed new images into the subspace using the learned deep architecture. The semantic and visual structures are jointly incorporated to learn a semantic subspace without overfitting the noisy, incomplete, or subjective tags. Besides, to remove the noisy or redundant visual features, a sparse model is imposed on the transformation matrix of the first layer in the deep architecture. Finally, a unified optimization problem with a well-defined objective function is developed to formulate the proposed problem and solved by a gradient descent procedure with curvilinear search. Extensive experiments on real-world social image databases are conducted on the tasks of image understanding: image tag refinement, assignment, and retrieval. Encouraging results are achieved with comparison with the state-of-the-art algorithms, which demonstrates the effectiveness of the proposed method.

Hierarchical Event Descriptors (HED): Semi-Structured Tagging for Real-World Events in Large-Scale EEG.

Real-world brain imaging by EEG requires accurate annotation of complex subject-environment interactions in event-rich tasks and paradigms. This paper describes the evolution of the Hierarchical Event Descriptor (HED) system for systematically describing both laboratory and real-world events. HED version 2, first described here, provides the semantic capability of describing a variety of subject and environmental states. HED descriptions can include stimulus presentation events on screen or in virtual worlds, experimental or spontaneous events occurring in the real world environment, and events experienced via one or multiple sensory modalities. Furthermore, HED 2 can distinguish between the mere presence of an object and its actual (or putative) perception by a subject. Although the HED framework has implicit ontological and linked data representations, the user-interface for HED annotation is more intuitive than traditional ontological annotation. We believe that hiding the formal representations allows for a more user-friendly interface, making consistent, detailed tagging of experimental, and real-world events possible for research users. HED is extensible while retaining the advantages of having an enforced common core vocabulary. We have developed a collection of tools to support HED tag assignment and validation; these are available at hedtags.org. A plug-in for EEGLAB (sccn.ucsd.edu/eeglab), CTAGGER, is also available to speed the process of tagging existing studies.

TagBook: A Semantic Video Representation Without Supervision for Event Detection

We consider the problem of event detection in video for scenarios where only a few, or even zero, examples are available for training. For this challenging setting, the prevailing solutions in the literature rely on a semantic video representation obtained from thousands of pretrained concept detectors. Different from existing work, we propose a new semantic video representation that is based on freely available social tagged videos only, without the need for training any intermediate concept detectors. We introduce a simple algorithm that propagates tags from a video's nearest neighbors, similar in spirit to the ones used for image retrieval, but redesign it for video event detection by including video source set refinement and varying the video tag assignment. We call our approach TagBook and study its construction, descriptiveness, and detection performance on the TRECVID 2013 and 2014 multimedia event detection datasets and the Columbia Consumer Video dataset. Despite its simple nature, the proposed TagBook video representation is remarkably effective for few-example and zero-example event detection, even outperforming very recent state-of-the-art alternatives building on supervised representations.

Socializing the Semantic Gap

Where previous reviews on content-based image retrieval emphasize what can be seen in an image to bridge the semantic gap, this survey considers what people tag about an image. A comprehensive treatise of three closely linked problems (i.e., image tag assignment, refinement, and tag-based image retrieval) is presented. While existing works vary in terms of their targeted tasks and methodology, they rely on the key functionality of tag relevance, that is, estimating the relevance of a specific tag with respect to the visual content of a given image and its social context. By analyzing what information a specific method exploits to construct its tag relevance function and how such information is exploited, this article introduces a two-dimensional taxonomy to structure the growing literature, understand the ingredients of the main works, clarify their connections and difference, and recognize their merits and limitations. For a head-to-head comparison with the state of the art, a new experimental protocol is presented, with training sets containing 10,000, 100,000, and 1 million images, and an evaluation on three test sets, contributed by various research groups. Eleven representative works are implemented and evaluated. Putting all this together, the survey aims to provide an overview of the past and foster progress for the near future.

Computational Methods for Coptic: Developing and Using Part-of-Speech Tagging for Digital Scholarship in the Humanities

This article motivates and details the first implementation of a freely available part of speech tag set and tagger for Coptic. Coptic is the last phase of the Egyptian language family and a descendant of the hieroglyphs of ancient Egypt. Unlike classical Greek and Latin, few resources for digital and computational work have existed for ancient Egyptian language and literature until now. We evaluate our tag set in an inter-annotator agreement experiment and examine some of the difficulties in tagging Coptic data. Using an existing digital lexicon and a small training corpus taken from several genres of literary Sahidic Coptic in the first half of the first millennium, we evaluate the performance of a stochastic tagger applying a fine-grained and coarse-grained set of tags within and outside the domain of literary texts. Our results show that a relatively high accuracy of 94–95% correct automatic tag assignment can be reached for literary texts, with substantially worse performance on documentary papyrus data. We also present some preliminary applications of natural language processing to the study of genre, style, and authorship attribution in Coptic and discuss future directions in applying computational linguistics methods to the analysis of Coptic texts.

Social Tagging: Exploring the Image, the Tags, and the Game

KO KNOWLEDGE ORGANIZATION , Seite 57 - 65

Assessing the relationships among tag syntax, semantics, and perceived usefulness

With the recent interest in socially created metadata as a potentially complementary resource for image description in relation to established tools such as thesauri and other forms of controlled vocabulary, questions remain about the quality and reuse value of these metadata. This study describes and examines a set of tags using quantitative and qualitative methods and assesses relationships among categories of image tags, tag assignment order, and users' perceptions of usefulness of index terms and user‐contributed tags. The study found that tags provide much descriptive information about an image but that users also value and trust controlled vocabulary terms. The study found no correlation between tag length and assignment order, and tag length and its perceived usefulness. The findings of this study can contribute to the design of controlled vocabularies, indexing processes, and retrieval systems for images. In particular, the findings of the study can advance the understanding of image tagging practices, tag facet/category distributions, relative usefulness and importance of these categories to the user, and potential mechanisms for identifying useful terms.

A Review of Ontology-Based Tag Recommendation Approaches

Tag recommender schemes suggest related tags for an untagged resource and better tag suggestions to tagged resources. Tagging is very important if the user identifies the tag that is more precise to use in searching interesting blogs. There is no clear information regarding the meaning of each tag in a tagging process. An user can use various tags for the same content, and he can also use new tags for an item in a blog. When the user selects tags, the resultant metadata may comprise homonyms and synonyms. This may cause an improper relationship among items and ineffective searches for topic information. The collaborative tag recommendation allows a set of freely selected text keywords as tags assigned by users. These tags are imprecise, irrelevant, and misleading because there is no control over the tag assignment. It does not follow any formal guidelines to assist tag generation, and tags are assigned to resources based on the knowledge of the users. This causes misspelled tags, multiple tags with the same meaning, bad word encoding, and personalized words without common meaning. This problem leads to miscategorization of items, irrelevant search results, wrong prediction, and their recommendations. Tag relevancy can be judged only by a specific user. These aspects could provide new challenges and opportunities to its tag recommendation problem. This paper reviews the challenges to meet the tag recommendation problem. A brief comparison between existing works is presented, which we can identify and point out the novel research directions. The overall performance of our ontology-based recommender systems is favorably compared to other systems in the literature.

Experts vs. Novices Tagging Behavior: An Exploratory Analysis

The universe of knowledge is not exclusively put in order by professionals any more. Traditional expert-oriented approaches are supplemented by organically-evolving user-generated approaches known as folksonomies. Their potentials (and disadvantages) as a new form of knowledge organization needs to be critically evaluated and scrutinized. This paper will review the notion of organization of information in contemporary information environments and contribute to findings and research data on tagging and folksonomies. The authors present results of a study in tagging behavior of an expert and novice group of users. By conducting the research on the student population two questions are being explored: a) what are specific differences in tagging behavior between experts and novices, and b) is the expertise acquired by students through course credits enough to create a significant difference in regard to the novice group with no formal education in the area. Differences of the two user groups in tag assignment are being analyzed with regard to tag number and distribution, both by using descriptive statistic and by introducing the tag efficiency measure. The results have shown that different efficiency levels in tag assignment between the two groups indicating that users with more knowledge and expertise could create folksonomies of higher quality.

폭소노미에 따른 웹 분류 연구 - 이용자 태깅 행위 분석을 중심으로 -

본 연구는 실제 폭소노미를 사용하는 참여자의 태깅 경험, 태깅과 폭소노미에 대한 인식을 파악하며, 폭소노미에 따른 웹 분류의 의미에 대해 탐구하고자 한다. 세 개의 폭소노미 시스템 Connotea, CiteULike, Delicious의 12명 참여자와 함께 정성적 연구의 틀 내에서 웹 설문, 인터뷰, 일기연구를 수행하였다. 참여자들의 태깅 행위를 이루는 기본구성요소를 파악하고, 태깅활동에 참여하게 되는 동기와 그 태깅동기들이 참여자들이 사용하는 태그에 어떻게 반영되는지를 조사하였다. 또한 정보탐색(information foraging) 이론을 적용하여 참여자들이 태깅을 통해 참여하는 사회성과 상호작용성에 대한 경험과 인식을 분석하고, 정보냄새로서의 태그에 대하여 논의하였다. 이용자 참여를 기반으로 하는 본 연구의 실증적 연구결과들은 폭소노미를 활용한 웹 정보서비스를 다양한 각도에서 이해하는데 도움을 주고, 웹 정보자원의 분류와 조직에 있어서 폭소노미의 유용화를 연구하는 개념적 틀을 제시함으로써 폭소노미 현상의 연구 향상에 기여할 수 있을 것으로 기대한다.

Mining multi-tag association for image tagging

Automatic media tagging plays a critical role in modern tag-based media retrieval systems. Existing tagging schemes mostly perform tag assignment based on community contributed media resources, where the tags are provided by users interactively. However, such social resources usually contain dirty and incomplete tags, which severely limit the performance of these tagging methods. In this paper, we propose a novel automatic image tagging method aiming to automatically discover more complete tags associated with information importance for test images. Given an image dataset, all the near-duplicate clusters are discovered. For each near-duplicate cluster, all the tags occurring in the cluster form the cluster's "document". Given a test image, we firstly initialize the candidate tag set from its near-duplicate cluster's document. The candidate tag set is then expanded by considering the implicit multi-tag associations mined from all the clusters' documents, where each cluster's document is regarded as a transaction. To further reduce noisy tags, a visual relevance score is also computed for each candidate tag to the test image based on a new tag model. Tags with very low scores can be removed from the final tag set. Extensive experiments conducted on a real-world web image dataset--NUS-WIDE, demonstrate the promising effectiveness of our approach.