Deep Learning
BioNLP-OST 2019 RDoC Tasks: Multi-grain Neural Relevance Ranking Using Topics and Attention Based Query-Document-Sentence Interactions
Chaudhary, Yatin, Gupta, Pankaj, Schรผtze, Hinrich
This paper presents our system details and results of participation in the RDoC Tasks of BioNLP-OST 2019. Research Domain Criteria (RDoC) construct is a multi-dimensional and broad framework to describe mental health disorders by combining knowledge from genomics to behaviour. Non-availability of RDoC labelled dataset and tedious labelling process hinders the use of RDoC framework to reach its full potential in Biomedical research community and Healthcare industry. Therefore, Task-1 aims at retrieval and ranking of PubMed abstracts relevant to a given RDoC construct and Task-2 aims at extraction of the most relevant sentence from a given PubMed abstract. We investigate (1) attention based supervised neural topic model and SVM for retrieval and ranking of PubMed abstracts and, further utilize BM25 and other relevance measures for re-ranking, (2) supervised and unsupervised sentence ranking models utilizing multi-view representations comprising of query-aware attention-based sentence representation (QAR), bag-of-words (BoW) and TF-IDF. Our best systems achieved 1st rank and scored 0.86 mean average precision (mAP) and 0.58 macro average accuracy (MAA) in Task-1 and Task-2 respectively.
Natural Language State Representation for Reinforcement Learning
Schwartz, Erez, Tennenholtz, Guy, Tessler, Chen, Mannor, Shie
Recent advances in Reinforcement Learning have highlighted the difficulties in learning within complex high dimensional domains. We argue that one of the main reasons that current approaches do not perform well, is that the information is represented sub-optimally. A natural way to describe what we observe, is through natural language. In this paper, we implement a natural language state representation to learn and complete tasks. Our experiments suggest that natural language based agents are more robust, converge faster and perform better than vision based agents, showing the benefit of using natural language representations for Reinforcement Learning.
Deep Reinforcement Learning for Single-Shot Diagnosis and Adaptation in Damaged Robots
Verma, Shresth, Nair, Haritha S., Agarwal, Gaurav, Dhar, Joydip, Shukla, Anupam
Robotics has proved to be an indispensable tool in many industrial as well as social applications, such as warehouse automation, manufacturing, disaster robotics, etc. In most of these scenarios, damage to the agent while accomplishing mission-critical tasks can result in failure. To enable robotic adaptation in such situations, the agent needs to adopt policies which are robust to a diverse set of damages and must do so with minimum computational complexity. We thus propose a damage aware control architecture which diagnoses the damage prior to gait selection while also incorporating domain randomization in the damage space for learning a robust policy. To implement damage awareness, we have used a Long Short Term Memory based supervised learning network which diagnoses the damage and predicts the type of damage. The main novelty of this approach is that only a single policy is trained to adapt against a wide variety of damages and the diagnosis is done in a single trial at the time of damage.
Stabilizing Off-Policy Reinforcement Learning with Conservative Policy Gradients
Tessler, Chen, Merlis, Nadav, Mannor, Shie
In recent years, advances in deep learning have enabled the application of reinforcement learning algorithms in complex domains. However, they lack the theoretical guarantees which are present in the tabular setting and suffer from many stability and reproducibility problems \citep{henderson2018deep}. In this work, we suggest a simple approach for improving stability and providing probabilistic performance guarantees in off-policy actor-critic deep reinforcement learning regimes. Experiments on continuous action spaces, in the MuJoCo control suite, show that our proposed method reduces the variance of the process and improves the overall performance.
Clinical Text Generation through Leveraging Medical Concept and Relations
Lee, Wangjin, Park, Hyeryun, Yoon, Jooyoung, Kim, Kyeongmo, Choi, Jinwook
With a neural sequence generation model, this study aims to develop a method of writing the patient clinical text s given a brief medical history. As a proof - of - a - concept, we have demonstrated that it can be workable t o use medical concept embedding in clinical text generation . Our model was based on the Sequence - to - Sequence architecture and trained with a large set of de - identified clinical text data . T he quantitative result shows that our concept embedding method decr eased the perplexity of the baseline architecture . Also, we discuss the analyzed r esults from a human evaluation performed by medical doctors .
Variational Temporal Abstraction
Kim, Taesup, Ahn, Sungjin, Bengio, Yoshua
We introduce a variational approach to learning and inference of temporally hierarchical structure and representation for sequential data. We propose the Variational Temporal Abstraction (VTA), a hierarchical recurrent state space model that can infer the latent temporal structure and thus perform the stochastic state transition hierarchically. We also propose to apply this model to implement the jumpy-imagination ability in imagination-augmented agent-learning in order to improve the efficiency of the imagination. In experiments, we demonstrate that our proposed method can model 2D and 3D visual sequence datasets with interpretable temporal structure discovery and that its application to jumpy imagination enables more efficient agent-learning in a 3D navigation task.
CWAE-IRL: Formulating a supervised approach to Inverse Reinforcement Learning problem
Inverse reinforcement learning (IRL) is used to infer the reward function from the actions of an expert running a Markov Decision Process (MDP). A novel approach using variational inference for learning the reward function is proposed in this research. Using this technique, the intractable posterior distribution of the continuous latent variable (the reward function in this case) is analytically approximated to appear to be as close to the prior belief while trying to reconstruct the future state conditioned on the current state and action. The reward function is derived using a well-known deep generative model known as Conditional Variational Auto-encoder (CVAE) with Wasserstein loss function, thus referred to as Conditional Wasserstein Auto-encoder-IRL (CWAE-IRL), which can be analyzed as a combination of the backward and forward inference. This can then form an efficient alternative to the previous approaches to IRL while having no knowledge of the system dynamics of the agent. Experimental results on standard benchmarks such as objectworld and pendulum show that the proposed algorithm can effectively learn the latent reward function in complex, high-dimensional environments.
Deep learning based super resolution, without using a GAN
This article describes the techniques and training a deep learning model for image improvement, image restoration, inpainting and super resolution. This utilises many techniques taught in the Fastai course and makes use of the Fastai software library. This method of training a model is based upon methods and research by very talented AI researchers, I've credited them where I have been able to in the information and techniques. As far as I'm aware some of the techniques I've applied with the training data are unique at this point with these learning methods (as of February 2019) and only a handful of researchers are using all these techniques together, who will mostly are likely to be Fastai researchers/students. Super resolution is the process of upscaling and or improving the details within an image. Often a low resolution image is taken as an input and the same image is upscaled to a higher resolution, which is the output.
Dyad X Machina: bringing emotion into machine learning (TensorFlow Meets)
Dyad X Machina is a research partnership that combines affective neuroscience and deep learning. In this episode, Laurence meets with the co-founder, Haohan Wang, who explains Dyad's mission as bringing emotion into machine learning. Haohan and her partner Christian created a course -- Applied Deep Learning with TensorFlow and Google Cloud AI -- that is the synthesis of their learning. It covers everything from building your first deep learning model to taking it all the way to deployment. Watch to learn more about the intersection of deep learning and affective computing and Haohan's four P's of learning.
Sometimes You Don't Need Deep Learning: Eye on A.I.
Ibrahim Gokcen, the digital chief technology officer for industrial giant Schneider Electric, has some words of caution about deep learning--the latest craze in artificial intelligence. Sometimes, conventional data crunching works just fine. All of the technology sold by Schneider that warns corporate customers when their industrial equipment may fail uses basic analytics or statistical analysis to make predictions. Although the software incorporates machine learning, it doesn't use deep learning, a technology that has led to breakthroughs in image and language translation. But that's okay, Gokcen explained.