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4IR: Convergence of Blockchain, AI and IOT

#artificialintelligence

Raneem Muhammed, a Blockchain consultant based in Saudi Arabia was interviewed by the Coinnewsextra team on the topic "4IR: Convergence of Blockchain, AI and IOT". The fourth industrial revolution also known as 4IR is the current and developing environment in which disruptive technologies and trends such as the Internet of Things (IoT), robotics, virtual reality (VR), Blockchain and artificial intelligence (AI) are changing the way we live and work. Ever since the third industrial revolution which pave way for the 4IR, the way we live changed drastically from the mechanical way of doing things during the First and Second revolution to a digital form. According to Raneem, "It would have a lot of different benefits along with negative effects." There are huge opportunities for individuals, society and the companies.


App promises to improve pain management in dementia patients

#artificialintelligence

University of Alberta computing scientists are developing an app to aid health-care staff to assess and manage pain in patients suffering from dementia and other neurodegenerative diseases. "The challenge with understanding pain in patients with dementia is that the expressions of pain in these individuals are often mistaken for psychiatric problems," said Eleni Stroulia, professor in the Department of Computing Science and co-lead on the project. "So we asked, how can we use technology to better understand the pain of people with dementia?" Along with Stroulia, the project is led by Thomas Hadjistavropoulos at the University of Regina as part of AGE-WELL, one of Canada's Networks of Centres of Excellence. The app will serve to digitize a pen-and-paper observational checklist that past research has shown helps health-care workers such as nurses when assessing pain in their patients suffering from dementia.


The Future of Data Science Networking & How You Can Benefit

#artificialintelligence

I am a community organizer for a group of 7,500 machine learning professionals. I work full-time organizing conferences, seminars, workshops and social initiatives. We began gathering in 2016 as a group of 30 people in the lobby of a co-working space. The meetups grew rapidly and in 2019 we were hosting events for 500 to 2,000 data scientists, machine learning engineers, data architects, researchers and entrepreneurs. Not surprisingly, Covid-19 has rocked our world.


Approximate Inverse Reinforcement Learning from Vision-based Imitation Learning

arXiv.org Artificial Intelligence

In this work, we present a method for obtaining an implicit objective function for vision-based navigation. The proposed methodology relies on Imitation Learning, Model Predictive Control (MPC), and Deep Learning. We use Imitation Learning as a means to do Inverse Reinforcement Learning in order to create an approximate costmap generator for a visual navigation challenge. The resulting costmap is used in conjunction with a Model Predictive Controller for real-time control and outperforms other state-of-the-art costmap generators combined with MPC in novel environments. The proposed process allows for simple training and robustness to out-of-sample data. We apply our method to the task of vision-based autonomous driving in multiple real and simulated environments using the same weights for the costmap predictor in all environments.


Localized active learning of Gaussian process state space models

arXiv.org Machine Learning

The performance of learning-based control techniques crucially depends on how effectively the system is explored. While most exploration techniques aim to achieve a globally accurate model, such approaches are generally unsuited for systems with unbounded state spaces. Furthermore, a globally accurate model is not required to achieve good performance in many common control applications, e.g., local stabilization tasks. In this paper, we propose an active learning strategy for Gaussian process state space models that aims to obtain an accurate model on a bounded subset of the state-action space. Our approach aims to maximize the mutual information of the exploration trajectories with respect to a discretization of the region of interest. By employing model predictive control, the proposed technique integrates information collected during exploration and adaptively improves its exploration strategy. To enable computational tractability, we decouple the choice of most informative data points from the model predictive control optimization step. This yields two optimization problems that can be solved in parallel. We apply the proposed method to explore the state space of various dynamical systems and compare our approach to a commonly used entropy-based exploration strategy. In all experiments, our method yields a better model within the region of interest than the entropy-based method.


Isotropic SGD: a Practical Approach to Bayesian Posterior Sampling

arXiv.org Machine Learning

In this work we define a unified mathematical framework to deepen our understanding of the role of stochastic gradient (SG) noise on the behavior of Markov chain Monte Carlo sampling (SGMCMC) algorithms. Our formulation unlocks the design of a novel, practical approach to posterior sampling, which makes the SG noise isotropic using a fixed learning rate that we determine analytically, and that requires weaker assumptions than existing algorithms. In contrast, the common traits of existing \sgmcmc algorithms is to approximate the isotropy condition either by drowning the gradients in additive noise (annealing the learning rate) or by making restrictive assumptions on the \sg noise covariance and the geometry of the loss landscape. Extensive experimental validations indicate that our proposal is competitive with the state-of-the-art on \sgmcmc, while being much more practical to use.


Neural Networks, Ridge Splines, and TV Regularization in the Radon Domain

arXiv.org Machine Learning

We develop a variational framework to understand the properties of the functions learned by neural networks fit to data. We propose and study a family of continuous-domain linear inverse problems with total variation-like regularization in the Radon domain subject to data fitting constraints. We derive a representer theorem showing that finite-width, singlehidden layer neural networks are solutions to these inverse problems. We draw on many techniques from variational spline theory and so we propose the notion of polynomial ridge splines, which correspond to a single-hidden layer neural networks with truncated power functions as the activation function. The representer theorem is reminiscent of the classical reproducing kernel Hilbert space representer theorem, but we show that the neural network problem is posed over a non-Hilbertian Banach space. While the learning problems are posed in the continuous-domain, similar to kernel methods, the problems can be recast as finite-dimensional neural network training problems. These neural network training problems have regularizers which are related to the well-known weight decay and path-norm regularizers. Thus, our result gives insight into functional characteristics of trained neural networks and also into the design neural network regularizers. We also show that these regularizers promote neural network solutions with desirable generalization properties.


Regret Balancing for Bandit and RL Model Selection

arXiv.org Machine Learning

We consider model selection in stochastic bandit and reinforcement learning problems. Given a set of base learning algorithms, an effective model selection strategy adapts to the best learning algorithm in an online fashion. We show that by estimating the regret of each algorithm and playing the algorithms such that all empirical regrets are ensured to be of the same order, the overall regret balancing strategy achieves a regret that is close to the regret of the optimal base algorithm. Our strategy requires an upper bound on the optimal base regret as input, and the performance of the strategy depends on the tightness of the upper bound. We show that having this prior knowledge is necessary in order to achieve a near-optimal regret. Further, we show that any near-optimal model selection strategy implicitly performs a form of regret balancing.


Graph-Aware Transformer: Is Attention All Graphs Need?

arXiv.org Machine Learning

Graphs are the natural data structure to represent relational and structural information in many domains. To cover the broad range of graph-data applications including graph classification as well as graph generation, it is desirable to have a general and flexible model consisting of an encoder and a decoder that can handle graph data. Although the representative encoder-decoder model, Transformer, shows superior performance in various tasks especially of natural language processing, it is not immediately available for graphs due to their non-sequential characteristics. To tackle this incompatibility, we propose GRaph-Aware Transformer (GRAT), the first Transformer-based model which can encode and decode whole graphs in end-to-end fashion. GRAT is featured with a self-attention mechanism adaptive to the edge information and an auto-regressive decoding mechanism based on the two-path approach consisting of sub-graph encoding path and node-and-edge generation path for each decoding step. We empirically evaluated GRAT on multiple setups including encoder-based tasks such as molecule property predictions on QM9 datasets and encoder-decoder-based tasks such as molecule graph generation in the organic molecule synthesis domain. GRAT has shown very promising results including state-of-the-art performance on 4 regression tasks in QM9 benchmark.


Recurrent Flow Networks: A Recurrent Latent Variable Model for Spatio-Temporal Density Modelling

arXiv.org Machine Learning

When modelling real-valued sequences, a typical approach in current RNN architectures is to use a Gaussian mixture model to describe the conditional output distribution. In this paper, we argue that mixture-based distributions could exhibit structural limitations when faced with highly complex data distributions such as for spatial densities. To address this issue, we introduce recurrent flow networks which combine deterministic and stochastic recurrent hidden states with conditional normalizing flows to form a probabilistic neural generative model capable of describing the kind of variability observed in highly structured spatio-temporal data. Inspired by the model's factorization, we further devise a structured variational inference network to approximate the intractable posterior distribution by exploiting a spatial representation of the data. We empirically evaluate our model against other generative models for sequential data on three real-world datasets for the task of spatio-temporal transportation demand modelling. Results show how the added flexibility allows our model to generate distributions matching potentially complex urban topologies.