Deep Learning
Deep Learning for Procedural Content Generation
Liu, Jialin, Snodgrass, Sam, Khalifa, Ahmed, Risi, Sebastian, Yannakakis, Georgios N., Togelius, Julian
Procedural content generation in video games has a long history. Existing procedural content generation methods, such as search-based, solver-based, rule-based and grammar-based methods have been applied to various content types such as levels, maps, character models, and textures. A research field centered on content generation in games has existed for more than a decade. More recently, deep learning has powered a remarkable range of inventions in content production, which are applicable to games. While some cutting-edge deep learning methods are applied on their own, others are applied in combination with more traditional methods, or in an interactive setting. This article surveys the various deep learning methods that have been applied to generate game content directly or indirectly, discusses deep learning methods that could be used for content generation purposes but are rarely used today, and envisages some limitations and potential future directions of deep learning for procedural content generation.
Recurrent babbling: evaluating the acquisition of grammar from limited input data
Pannitto, Ludovica, Herbelot, Aurélie
In contrast with previous models: (i) we train a Artificial Neural Networks, and Long Short-Term vanilla char-LSTM on a more realistic variety and Memory Networks more specifically, have consistently amount of data, focusing on a limited amount of demonstrated great capabilities in the area child-directed language; (ii) we do not rely on extrinsic of language modeling. In addition to generating evaluations or downstream tasks, instead we credible surface patterns, they show excellent performances introduce a methodology to evaluate how the distribution when tested on very specific grammatical of grammatical items, over time, comes abilities (Gulordava et al., 2018; Lakretz et al., to approximate the one in the input, through a continuous 2019), without requiring any prior bias towards the process and (iii) we tentatively explore the syntactic structure of natural languages.
Deep Partial Updating
Qu, Zhongnan, Liu, Cong, Guo, Junfeng, Thiele, Lothar
Emerging edge intelligence applications require the server to continuously retrain and update deep neural networks deployed on remote edge nodes in order to leverage newly collected data samples. Unfortunately, it may be impossible in practice to continuously send fully updated weights to these edge nodes due to the highly constrained communication resource. In this paper, we propose the weight-wise deep partial updating paradigm, which smartly selects only a subset of weights to update at each server-to-edge communication round, while achieving a similar performance compared to full updating. Our method is established through analytically upper-bounding the loss difference between partial updating and full updating, and only updates the weights which make the largest contributions to the upper bound. Extensive experimental results demonstrate the efficacy of our partial updating methodology which achieves a high inference accuracy while updating a rather small number of weights.
Towards User Friendly Medication Mapping Using Entity-Boosted Two-Tower Neural Network
Yuan, Shaoqing, Bhatia, Parminder, Celikkaya, Busra, Liu, Haiyang, Choi, Kyunghwan
Recent advancements in medical entity linking have been applied in the area of scientific literature and social media data. However, with the adoption of telemedicine and conversational agents such as Alexa in healthcare settings, medical name inference has become an important task. Medication name inference is the task of mapping user friendly medication names from a free-form text to a concept in a normalized medication list. This is challenging due to the differences in the use of medical terminology from health care professionals and user conversations coming from the lay public. We begin with mapping descriptive medication phrases (DMP) to standard medication names (SMN). Given the prescriptions of each patient, we want to provide them with the flexibility of referring to the medication in their preferred ways. We approach this as a ranking problem which maps SMN to DMP by ordering the list of medications in the patient's prescription list obtained from pharmacies. Furthermore, we leveraged the output of intermediate layers and performed medication clustering. We present the Medication Inference Model (MIM) achieving state-of-the-art results. By incorporating medical entities based attention, we have obtained further improvement for ranking models.
Identifying Risk of Opioid Use Disorder for Patients Taking Opioid Medications with Deep Learning
Dong, Xinyu, Deng, Jianyuan, Rashidian, Sina, Abell-Hart, Kayley, Hou, Wei, Rosenthal, Richard N, Saltz, Mary, Saltz, Joel, Wang, Fusheng
The United States is experiencing an opioid epidemic, and there were more than 10 million opioid misusers aged 12 or older each year. Identifying patients at high risk of Opioid Use Disorder (OUD) can help to make early clinical interventions to reduce the risk of OUD. Our goal is to predict OUD patients among opioid prescription users through analyzing electronic health records with machine learning and deep learning methods. This will help us to better understand the diagnoses of OUD, providing new insights on opioid epidemic. Electronic health records of patients who have been prescribed with medications containing active opioid ingredients were extracted from Cerner Health Facts database between January 1, 2008 and December 31, 2017. Long Short-Term Memory (LSTM) models were applied to predict opioid use disorder risk in the future based on recent five encounters, and compared to Logistic Regression, Random Forest, Decision Tree and Dense Neural Network. Prediction performance was assessed using F-1 score, precision, recall, and AUROC. Our temporal deep learning model provided promising prediction results which outperformed other methods, with a F1 score of 0.8023 and AUCROC of 0.9369. The model can identify OUD related medications and vital signs as important features for the prediction. LSTM based temporal deep learning model is effective on predicting opioid use disorder using a patient past history of electronic health records, with minimal domain knowledge. It has potential to improve clinical decision support for early intervention and prevention to combat the opioid epidemic.
Incorporating planning intelligence into deep learning: A planning support tool for street network design
Fang, Zhou, Jin, Ying, Yang, Tianren
With the emergence of deep learning techniques, procedural and example-based modeling have been increasingly applied to support automatic content generation and visualization for planning decisions (Hartmann et al., 2017). Procedural modeling relies on manually designated rule sets to produce proposals. Parish and Müller (2001) made one of the first attempts to generate three-dimensional city models for visualization using procedural approaches, where a Lindenmayer system was used to grow road networks and buildings conditioned on global goals and local constraints. Given an initial and a final road point, Galin et al. (2010) developed a cost minimization function to automate path creation, considering the slope of the terrain and natural obstacles. The function was then extended to generate hierarchical road networks between towns at a regional level (Galin et al., 2011). Similar procedural principles can also be applied to allocate land use, subdivide blocks and generate buildings (see, e.g., Chen et al., 2008; Lyu et al., 2015). In comparison, example-based approaches learn from real-world cases in a preprocessing step to extract features and adopt them as templates. Hartmann et al. (2017) developed an automatic road generation tool, StreetGAN, using a generative adversarial network (GAN) to synthesize street networks in a fix-sized region that can maintain the consistency of urban layouts learned from the training data set. Similarly, Kempinska and Murcio (2019) trained Variational Autoencoders (VAEs) using images of street networks derived from OpenStreetMap to capture urban configurations using lowdimensional vectors and generating new street networks by controlling the encoded vectors.
TaxiNLI: Taking a Ride up the NLU Hill
Joshi, Pratik, Aditya, Somak, Sathe, Aalok, Choudhury, Monojit
Pre-trained Transformer-based neural architectures have consistently achieved state-of-the-art performance in the Natural Language Inference (NLI) task. Since NLI examples encompass a variety of linguistic, logical, and reasoning phenomena, it remains unclear as to which specific concepts are learnt by the trained systems and where they can achieve strong generalization. To investigate this question, we propose a taxonomic hierarchy of categories that are relevant for the NLI task. We introduce TAXINLI, a new dataset, that has 10k examples from the MNLI dataset (Williams et al., 2018) with these taxonomic labels. Through various experiments on TAXINLI, we observe that whereas for certain taxonomic categories SOTA neural models have achieved near perfect accuracies - a large jump over the previous models - some categories still remain difficult. Our work adds to the growing body of literature that shows the gaps in the current NLI systems and datasets through a systematic presentation and analysis of reasoning categories.
GitEvolve: Predicting the Evolution of GitHub Repositories
Zhou, Honglu, Ravi, Hareesh, Muniz, Carlos M., Azizi, Vahid, Ness, Linda, de Melo, Gerard, Kapadia, Mubbasir
Software development is becoming increasingly open and collaborative with the advent of platforms such as GitHub. Given its crucial role, there is a need to better understand and model the dynamics of GitHub as a social platform. Previous work has mostly considered the dynamics of traditional social networking sites like Twitter and Facebook. We propose GitEvolve, a system to predict the evolution of GitHub repositories and the different ways by which users interact with them. To this end, we develop an end-to-end multi-task sequential deep neural network that given some seed events, simultaneously predicts which user-group is next going to interact with a given repository, what the type of the interaction is, and when it happens. To facilitate learning, we use graph based representation learning to encode relationship between repositories. We map users to groups by modelling common interests to better predict popularity and to generalize to unseen users during inference. We introduce an artificial event type to better model varying levels of activity of repositories in the dataset. The proposed multi-task architecture is generic and can be extended to model information diffusion in other social networks. In a series of experiments, we demonstrate the effectiveness of the proposed model, using multiple metrics and baselines. Qualitative analysis of the model's ability to predict popularity and forecast trends proves its applicability.
EpidemiOptim: A Toolbox for the Optimization of Control Policies in Epidemiological Models
Colas, Cédric, Hejblum, Boris, Rouillon, Sébastien, Thiébaut, Rodolphe, Oudeyer, Pierre-Yves, Moulin-Frier, Clément, Prague, Mélanie
Epidemiologists model the dynamics of epidemics in order to propose control strategies based on pharmaceutical and non-pharmaceutical interventions (contact limitation, lock down, vaccination, etc). Hand-designing such strategies is not trivial because of the number of possible interventions and the difficulty to predict long-term effects. This task can be cast as an optimization problem where state-of-the-art machine learning algorithms such as deep reinforcement learning, might bring significant value. However, the specificity of each domain -- epidemic modelling or solving optimization problem -- requires strong collaborations between researchers from different fields of expertise. This is why we introduce EpidemiOptim, a Python toolbox that facilitates collaborations between researchers in epidemiology and optimization. EpidemiOptim turns epidemiological models and cost functions into optimization problems via a standard interface commonly used by optimization practitioners (OpenAI Gym). Reinforcement learning algorithms based on Q-Learning with deep neural networks (DQN) and evolutionary algorithms (NSGA-II) are already implemented. We illustrate the use of EpidemiOptim to find optimal policies for dynamical on-off lock-down control under the optimization of death toll and economic recess using a Susceptible-Exposed-Infectious-Removed (SEIR) model for COVID-19. Using EpidemiOptim and its interactive visualization platform in Jupyter notebooks, epidemiologists, optimization practitioners and others (e.g. economists) can easily compare epidemiological models, costs functions and optimization algorithms to address important choices to be made by health decision-makers.
Rao-Blackwellizing the Straight-Through Gumbel-Softmax Gradient Estimator
Paulus, Max B., Maddison, Chris J., Krause, Andreas
Gradient estimation in models with discrete latent variables is a challenging problem, because the simplest unbiased estimators tend to have high variance. To counteract this, modern estimators either introduce bias, rely on multiple function evaluations, or use learned, input-dependent baselines. Thus, there is a need for estimators that require minimal tuning, are computationally cheap, and have low mean squared error. In this paper, we show that the variance of the straight-through variant of the popular Gumbel-Softmax estimator can be reduced through Rao-Blackwellization without increasing the number of function evaluations. This provably reduces the mean squared error. We empirically demonstrate that this leads to variance reduction, faster convergence, and generally improved performance in two unsupervised latent variable models.