421 research outputs found
Econometrics meets sentiment : an overview of methodology and applications
The advent of massive amounts of textual, audio, and visual data has spurred the development of econometric methodology to transform qualitative sentiment data into quantitative sentiment variables, and to use those variables in an econometric analysis of the relationships between sentiment and other variables. We survey this emerging research field and refer to it as sentometrics, which is a portmanteau of sentiment and econometrics. We provide a synthesis of the relevant methodological approaches, illustrate with empirical results, and discuss useful software
An Attention-Based Model for Predicting Contextual Informativeness and Curriculum Learning Applications
Both humans and machines learn the meaning of unknown words through
contextual information in a sentence, but not all contexts are equally helpful
for learning. We introduce an effective method for capturing the level of
contextual informativeness with respect to a given target word. Our study makes
three main contributions. First, we develop models for estimating contextual
informativeness, focusing on the instructional aspect of sentences. Our
attention-based approach using pre-trained embeddings demonstrates
state-of-the-art performance on our single-context dataset and an existing
multi-sentence context dataset. Second, we show how our model identifies key
contextual elements in a sentence that are likely to contribute most to a
reader's understanding of the target word. Third, we examine how our contextual
informativeness model, originally developed for vocabulary learning
applications for students, can be used for developing better training curricula
for word embedding models in batch learning and few-shot machine learning
settings. We believe our results open new possibilities for applications that
support language learning for both human and machine learner
The Benefits of Word Embeddings Features for Active Learning in Clinical Information Extraction
This study investigates the use of unsupervised word embeddings and sequence
features for sample representation in an active learning framework built to
extract clinical concepts from clinical free text. The objective is to further
reduce the manual annotation effort while achieving higher effectiveness
compared to a set of baseline features. Unsupervised features are derived from
skip-gram word embeddings and a sequence representation approach. The
comparative performance of unsupervised features and baseline hand-crafted
features in an active learning framework are investigated using a wide range of
selection criteria including least confidence, information diversity,
information density and diversity, and domain knowledge informativeness. Two
clinical datasets are used for evaluation: the i2b2/VA 2010 NLP challenge and
the ShARe/CLEF 2013 eHealth Evaluation Lab. Our results demonstrate significant
improvements in terms of effectiveness as well as annotation effort savings
across both datasets. Using unsupervised features along with baseline features
for sample representation lead to further savings of up to 9% and 10% of the
token and concept annotation rates, respectively
Neural models of language use:Studies of language comprehension and production in context
Artificial neural network models of language are mostly known and appreciated today for providing a backbone for formidable AI technologies. This thesis takes a different perspective. Through a series of studies on language comprehension and production, it investigates whether artificial neural networks—beyond being useful in countless AI applications—can serve as accurate computational simulations of human language use, and thus as a new core methodology for the language sciences
Deep Active Learning for Swedish Named Entity Recognition An empiric evaluation of active learning algorithms for Named Entity Recognition
Named entity recognition holds promise for numerous practical applications involving
text data, such as keyword extraction and automated anonymization. However,
successfully train a machine learning model for Named Entity Recognition is challenging
due to the amount of annotated data required, especially for cases where
language that is not globally common such as Swedish is involved. In such cases,
using a Deep pre-trained model such as BERT in conjunction with the practice of
active learning may be preferred. To obtain some insight into the implementation of
such an approach, this thesis serves as an empirical study of various active learning
strategies when used in conjunction with BERT-based name entity recognition. The
performance of different active learning algorithms and the effect of acquisition size
on the performance of active learning is the main focus of this study. In conclusion,
after comparing and evaluating 17 different active learning methods, the study’s
empirical results demonstrate entropy sampling to be the best performing active
learning algorithm for Named Entity Recognition of Swedish texts, and the choice
of acquisition sizes is practically negligible to performance
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