13,378 research outputs found
Unsupervised Methods for Determining Object and Relation Synonyms on the Web
The task of identifying synonymous relations and objects, or synonym
resolution, is critical for high-quality information extraction. This paper
investigates synonym resolution in the context of unsupervised information
extraction, where neither hand-tagged training examples nor domain knowledge is
available. The paper presents a scalable, fully-implemented system that runs in
O(KN log N) time in the number of extractions, N, and the maximum number of
synonyms per word, K. The system, called Resolver, introduces a probabilistic
relational model for predicting whether two strings are co-referential based on
the similarity of the assertions containing them. On a set of two million
assertions extracted from the Web, Resolver resolves objects with 78% precision
and 68% recall, and resolves relations with 90% precision and 35% recall.
Several variations of resolvers probabilistic model are explored, and
experiments demonstrate that under appropriate conditions these variations can
improve F1 by 5%. An extension to the basic Resolver system allows it to handle
polysemous names with 97% precision and 95% recall on a data set from the TREC
corpus
FarsBase-KBP: A Knowledge Base Population System for the Persian Knowledge Graph
While most of the knowledge bases already support the English language, there
is only one knowledge base for the Persian language, known as FarsBase, which
is automatically created via semi-structured web information. Unlike English
knowledge bases such as Wikidata, which have tremendous community support, the
population of a knowledge base like FarsBase must rely on automatically
extracted knowledge. Knowledge base population can let FarsBase keep growing in
size, as the system continues working. In this paper, we present a knowledge
base population system for the Persian language, which extracts knowledge from
unlabeled raw text, crawled from the Web. The proposed system consists of a set
of state-of-the-art modules such as an entity linking module as well as
information and relation extraction modules designed for FarsBase. Moreover, a
canonicalization system is introduced to link extracted relations to FarsBase
properties. Then, the system uses knowledge fusion techniques with minimal
intervention of human experts to integrate and filter the proper knowledge
instances, extracted by each module. To evaluate the performance of the
presented knowledge base population system, we present the first gold dataset
for benchmarking knowledge base population in the Persian language, which
consisting of 22015 FarsBase triples and verified by human experts. The
evaluation results demonstrate the efficiency of the proposed system.Comment: 39 pages, 6 figure
Self-supervised Visual Feature Learning with Deep Neural Networks: A Survey
Large-scale labeled data are generally required to train deep neural networks
in order to obtain better performance in visual feature learning from images or
videos for computer vision applications. To avoid extensive cost of collecting
and annotating large-scale datasets, as a subset of unsupervised learning
methods, self-supervised learning methods are proposed to learn general image
and video features from large-scale unlabeled data without using any
human-annotated labels. This paper provides an extensive review of deep
learning-based self-supervised general visual feature learning methods from
images or videos. First, the motivation, general pipeline, and terminologies of
this field are described. Then the common deep neural network architectures
that used for self-supervised learning are summarized. Next, the main
components and evaluation metrics of self-supervised learning methods are
reviewed followed by the commonly used image and video datasets and the
existing self-supervised visual feature learning methods. Finally, quantitative
performance comparisons of the reviewed methods on benchmark datasets are
summarized and discussed for both image and video feature learning. At last,
this paper is concluded and lists a set of promising future directions for
self-supervised visual feature learning
Fine-grained Recognition in the Wild: A Multi-Task Domain Adaptation Approach
While fine-grained object recognition is an important problem in computer
vision, current models are unlikely to accurately classify objects in the wild.
These fully supervised models need additional annotated images to classify
objects in every new scenario, a task that is infeasible. However, sources such
as e-commerce websites and field guides provide annotated images for many
classes. In this work, we study fine-grained domain adaptation as a step
towards overcoming the dataset shift between easily acquired annotated images
and the real world. Adaptation has not been studied in the fine-grained setting
where annotations such as attributes could be used to increase performance. Our
work uses an attribute based multi-task adaptation loss to increase accuracy
from a baseline of 4.1% to 19.1% in the semi-supervised adaptation case. Prior
do- main adaptation works have been benchmarked on small datasets such as [46]
with a total of 795 images for some domains, or simplistic datasets such as
[41] consisting of digits. We perform experiments on a subset of a new
challenging fine-grained dataset consisting of 1,095,021 images of 2, 657 car
categories drawn from e-commerce web- sites and Google Street View.Comment: ICCV 201
A review of EO image information mining
We analyze the state of the art of content-based retrieval in Earth
observation image archives focusing on complete systems showing promise for
operational implementation. The different paradigms at the basis of the main
system families are introduced. The approaches taken are analyzed, focusing in
particular on the phases after primitive feature extraction. The solutions
envisaged for the issues related to feature simplification and synthesis,
indexing, semantic labeling are reviewed. The methodologies for query
specification and execution are analyzed
Unsupervised Induction of Contingent Event Pairs from Film Scenes
Human engagement in narrative is partially driven by reasoning about
discourse relations between narrative events, and the expectations about what
is likely to happen next that results from such reasoning. Researchers in NLP
have tackled modeling such expectations from a range of perspectives, including
treating it as the inference of the contingent discourse relation, or as a type
of common-sense causal reasoning. Our approach is to model likelihood between
events by drawing on several of these lines of previous work. We implement and
evaluate different unsupervised methods for learning event pairs that are
likely to be contingent on one another. We refine event pairs that we learn
from a corpus of film scene descriptions utilizing web search counts, and
evaluate our results by collecting human judgments of contingency. Our results
indicate that the use of web search counts increases the average accuracy of
our best method to 85.64% over a baseline of 50%, as compared to an average
accuracy of 75.15% without web search
A Survey on Web Multimedia Mining
Modern developments in digital media technologies has made transmitting and
storing large amounts of multi/rich media data (e.g. text, images, music, video
and their combination) more feasible and affordable than ever before. However,
the state of the art techniques to process, mining and manage those rich media
are still in their infancy. Advances developments in multimedia acquisition and
storage technology the rapid progress has led to the fast growing incredible
amount of data stored in databases. Useful information to users can be revealed
if these multimedia files are analyzed. Multimedia mining deals with the
extraction of implicit knowledge, multimedia data relationships, or other
patterns not explicitly stored in multimedia files. Also in retrieval, indexing
and classification of multimedia data with efficient information fusion of the
different modalities is essential for the system's overall performance. The
purpose of this paper is to provide a systematic overview of multimedia mining.
This article is also represents the issues in the application process component
for multimedia mining followed by the multimedia mining models.Comment: 13 Pages; The International Journal of Multimedia & Its Applications
(IJMA) Vol.3, No.3, August 201
Using Rank Aggregation for Expert Search in Academic Digital Libraries
The task of expert finding has been getting increasing attention in
information retrieval literature. However, the current state-of-the-art is
still lacking in principled approaches for combining different sources of
evidence. This paper explores the usage of unsupervised rank aggregation
methods as a principled approach for combining multiple estimators of
expertise, derived from the textual contents, from the graph-structure of the
citation patterns for the community of experts, and from profile information
about the experts. We specifically experimented two unsupervised rank
aggregation approaches well known in the information retrieval literature,
namely CombSUM and CombMNZ. Experiments made over a dataset of academic
publications for the area of Computer Science attest for the adequacy of these
methods.Comment: In Simp\'{o}sio de Inform\'{a}tica, INForum, Portugal, 201
Watch-Bot: Unsupervised Learning for Reminding Humans of Forgotten Actions
We present a robotic system that watches a human using a Kinect v2 RGB-D
sensor, detects what he forgot to do while performing an activity, and if
necessary reminds the person using a laser pointer to point out the related
object. Our simple setup can be easily deployed on any assistive robot.
Our approach is based on a learning algorithm trained in a purely
unsupervised setting, which does not require any human annotations. This makes
our approach scalable and applicable to variant scenarios. Our model learns the
action/object co-occurrence and action temporal relations in the activity, and
uses the learned rich relationships to infer the forgotten action and the
related object. We show that our approach not only improves the unsupervised
action segmentation and action cluster assignment performance, but also
effectively detects the forgotten actions on a challenging human activity RGB-D
video dataset. In robotic experiments, we show that our robot is able to remind
people of forgotten actions successfully
Machine Learning with World Knowledge: The Position and Survey
Machine learning has become pervasive in multiple domains, impacting a wide
variety of applications, such as knowledge discovery and data mining, natural
language processing, information retrieval, computer vision, social and health
informatics, ubiquitous computing, etc. Two essential problems of machine
learning are how to generate features and how to acquire labels for machines to
learn. Particularly, labeling large amount of data for each domain-specific
problem can be very time consuming and costly. It has become a key obstacle in
making learning protocols realistic in applications. In this paper, we will
discuss how to use the existing general-purpose world knowledge to enhance
machine learning processes, by enriching the features or reducing the labeling
work. We start from the comparison of world knowledge with domain-specific
knowledge, and then introduce three key problems in using world knowledge in
learning processes, i.e., explicit and implicit feature representation,
inference for knowledge linking and disambiguation, and learning with direct or
indirect supervision. Finally we discuss the future directions of this research
topic
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