Deep Learning
Feature-Less End-to-End Nested Term Extraction
In this paper, we proposed a deep learning-based end-to-end method on the domain specified automatic term extraction (ATE), it considers possible term spans within a fixed length in the sentence and predicts them whether they can be conceptual terms. In comparison with current ATE methods, the model supports nested term extraction and does not crucially need extra (extracted) features. Results show that it can achieve high recall and a comparable precision on term extraction task with inputting segmented raw text.
TAPER: Time-Aware Patient EHR Representation
Darabi, Sajad, Kachuee, Mohammad, Fazeli, Shayan, Sarrafzadeh, Majid
--Effective representation learning of electronic health records is a challenging task and is becoming more important as the availability of such data is becoming pervasive. The data contained in these records are irregular and contain multiple modalities such as notes, and medical codes. They are preempted by medical conditions the patient may have, and are typically recorded by medical staff. Accompanying codes are notes containing valuable information about patients beyond the structured information contained in electronic health records. We use transformer networks and the recently proposed BERT language model to embed these data streams into a unified vector representation. The presented approach effectively encodes a patient's visit data into a single distributed representation, which can be used for downstream tasks. Our model demonstrates superior performance and generalization on mortality, readmission and length of stay tasks using the publicly available MIMIC-III ICU dataset. LECTRONIC health records (EHR) are commonly adopted in hospitals to improve patient care. In an intensive care unit (ICU), various data sources are collected on a daily basis as preempted by medical staff as the patient undergoes care in the unit. The collected data consists of data from different modalities: medical codes such as diagnosis which are standardized by well-organized ontology's like the International Classification of Disease (ICD) Additionally, lab tests and bedside monitoring devices are used to collect signals each of which are collected at varying frequencies for a quantitative measure of the patient care.
Unsupervised Discovery of Decision States for Transfer in Reinforcement Learning
Modhe, Nirbhay, Chattopadhyay, Prithvijit, Sharma, Mohit, Das, Abhishek, Parikh, Devi, Batra, Dhruv, Vedantam, Ramakrishna
We present a hierarchical reinforcement learning (HRL) or options framework for identifying decision states. Informally speaking, these are states considered important by the agent's policy e.g. , for navigation, decision states would be crossroads or doors where an agent needs to make strategic decisions. While previous work (most notably Goyal et. al., 2019) discovers decision states in a task/goal specific (or 'supervised') manner, we do so in a goal-independent (or 'unsupervised') manner, i.e. entirely without any goal or extrinsic rewards. Our approach combines two hitherto disparate ideas - 1) \emph{intrinsic control} (Gregor et. al., 2016, Eysenbach et. al., 2018): learning a set of options that allow an agent to reliably reach a diverse set of states, and 2) \emph{information bottleneck} (Tishby et. al., 2000): penalizing mutual information between the option $\Omega$ and the states $s_t$ visited in the trajectory. The former encourages an agent to reliably explore the environment; the latter allows identification of decision states as the ones with high mutual information $I(\Omega; a_t | s_t)$ despite the bottleneck. Our results demonstrate that 1) our model learns interpretable decision states in an unsupervised manner, and 2) these learned decision states transfer to goal-driven tasks in new environments, effectively guide exploration, and improve performance.
Natural Language Processing of Clinical Notes on Chronic Diseases: Systematic Review
Sheikhalishahi, Seyedmostafa, Miotto, Riccardo, Dudley, Joel T, Lavelli, Alberto, Rinaldi, Fabio, Osmani, Venet
Of the 2652 articles considered, 106 met the inclusion criteria. Review of the included papers resulted in identification of 43 chronic diseases, which were then further classified into 10 disease categories using ICD-10. The majority of studies focused on diseases of the circulatory system (n=38) while endocrine and metabolic diseases were fewest (n=14). This was due to the structure of clinical records related to metabolic diseases, which typically contain much more structured data, compared with medical records for diseases of the circulatory system, which focus more on unstructured data and consequently have seen a stronger focus of NLP. The review has shown that there is a significant increase in the use of machine learning methods compared to rule-based approaches; however, deep learning methods remain emergent (n=3). Consequently, the majority of works focus on classification of disease phenotype with only a handful of papers addressing extraction of comorbidities from the free text or integration of clinical notes with structured data. There is a notable use of relatively simple methods, such as shallow classifiers (or combination with rule-based methods), due to the interpretability of predictions, which still represents a significant issue for more complex methods. Finally, scarcity of publicly available data may also have contributed to insufficient development of more advanced methods, such as extraction of word embeddings from clinical notes. Further efforts are still required to improve (1) progression of clinical NLP methods from extraction toward understanding; (2) recognition of relations among entities rather than entities in isolation; (3) temporal extraction to understand past, current, and future clinical events; (4) exploitation of alternative sources of clinical knowledge; and (5) availability of large-scale, de-identified clinical corpora.
Conditional LSTM-GAN for Melody Generation from Lyrics
--Melody generation from lyrics has been a challenging research issue in the field of artificial intelligence and music, which enables to learn and discover latent relationship between interesting lyrics and accompanying melody. Unfortunately, the limited availability of paired lyrics-melody dataset with alignment information has hindered the research progress. T o address this problem, we create a large dataset consisting of 12,197 MIDI songs each with paired lyrics and melody alignment through leveraging different music sources where alignment relationship between syllables and music attributes is extracted. Most importantly, we propose a novel deep generative model, conditional Long Short-T erm Memory - Generative Adversarial Network (LSTM-GAN) for melody generation from lyrics, which contains a deep LSTM generator and a deep LSTM discriminator both conditioned on lyrics. In particular, lyrics-conditioned melody and alignment relationship between syllables of given lyrics and notes of predicted melody are generated simultaneously. Experimental results have proved the effectiveness of our proposed lyrics-to-melody generative model, where plausible and tuneful sequences can be inferred from lyrics. I NTRODUCTION Music generation is also referred to as music composition with the process of creating or writing an original piece of music, which is one of human creative activities [1]. Without understanding music rules and concepts well, creating pleasing sounds is impossible. To learn these kinds of rules and concepts such as mathematical relationships between notes, timing, and melody, the earliest study of various music computational techniques related to Artificial Intelligence (AI) has emerged for music composition in the middle of 1950s [2]. Markov models as a representative method of machine learning have been applied to algorithmic composition [3]. However, due to the limited availability of paired lyrics-melody dataset with alignment information, research progress of lyrics-conditioned music generation has been obstructed.
Multi-class Hierarchical Question Classification for Multiple Choice Science Exams
Xu, Dongfang, Jansen, Peter, Martin, Jaycie, Xie, Zhengnan, Yadav, Vikas, Madabushi, Harish Tayyar, Tafjord, Oyvind, Clark, Peter
Prior work has demonstrated that question classification (QC), recognizing the problem domain of a question, can help answer it more accurately. However, developing strong QC algorithms has been hindered by the limited size and complexity of annotated data available. To address this, we present the largest challenge dataset for QC, containing 7,787 science exam questions paired with detailed classification labels from a fine-grained hierarchical taxonomy of 406 problem domains. We then show that a BERT-based model trained on this dataset achieves a large (+0.12 MAP) gain compared with previous methods, while also achieving state-of-the-art performance on benchmark open-domain and biomedical QC datasets. Finally, we show that using this model's predictions of question topic significantly improves the accuracy of a question answering system by +1.7% P@1, with substantial future gains possible as QC performance improves.
Deep Learning for NLP: ANNs, RNNs and LSTMs explained!
Ever fantasied about having your own personal assistant to answer any questions you can ask, or have conversations with? Well, thanks to Machine Learning and Deep Neural Networks, this is not so far from happening. Think of the amazing capabilities exhibited by Apple's Siri or Amazon's Alexa. Don't get too excited, in this next series of posts we are not going to create an omnipotent Artificial Intelligence, rather we will create a simple chatbot that given some input information and a question about such information, responds to yes/no questions regarding what it has been told. It is nowhere near to Siri's or Alexa's capabilities, but it illustrates very well how even using very simple deep neural network structures, amazing results can be obtained.
DeepMind's Losses and the Future of Artificial Intelligence
Alphabet's DeepMind lost $572 million last year. DeepMind, likely the world's largest research-focused artificial intelligence operation, is losing a lot of money fast, more than $1 billion in the past three years. DeepMind also has more than $1 billion in debt due in the next 12 months. Does this mean that AI is falling apart? Gary Marcus is founder and CEO of Robust.AI and a professor of psychology and neural science at NYU.
DeepMind's Losses and the Future of Artificial Intelligence
Alphabet's DeepMind lost $572 million last year. DeepMind, likely the world's largest research-focused artificial intelligence operation, is losing a lot of money fast, more than $1 billion in the past three years. DeepMind also has more than $1 billion in debt due in the next 12 months. Does this mean that AI is falling apart? Gary Marcus is founder and CEO of Robust.AI and a professor of psychology and neural science at NYU.
AutoML: A Survey of the State-of-the-Art
He, Xin, Zhao, Kaiyong, Chu, Xiaowen
Deep learning has penetrated all aspects of our lives and brought us great convenience. However, the process of building a high-quality deep learning system for a specific task is not only time-consuming but also requires lots of resources and relies on human expertise, which hinders the development of deep learning in both industry and academia. To alleviate this problem, a growing number of research projects focus on automated machine learning (AutoML). In this paper, we provide a comprehensive and up-to-date study on the state-of-the-art AutoML. First, we introduce the AutoML techniques in details according to the machine learning pipeline. Then we summarize existing Neural Architecture Search (NAS) research, which is one of the most popular topics in AutoML. We also compare the models generated by NAS algorithms with those human-designed models. Finally, we present several open problems for future research.