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Three scenarios for continual learning

arXiv.org Artificial Intelligence

Standard artificial neural networks suffer from the well-known issue of catastrophic forgetting, making continual or lifelong learning difficult for machine learning. In recent years, numerous methods have been proposed for continual learning, but due to differences in evaluation protocols it is difficult to directly compare their performance. To enable more structured comparisons, we describe three continual learning scenarios based on whether at test time task identity is provided and--in case it is not--whether it must be inferred. Any sequence of well-defined tasks can be performed according to each scenario. Using the split and permuted MNIST task protocols, for each scenario we carry out an extensive comparison of recently proposed continual learning methods. We demonstrate substantial differences between the three scenarios in terms of difficulty and in terms of how efficient different methods are. In particular, when task identity must be inferred (i.e., class incremental learning), we find that regularization-based approaches (e.g., elastic weight consolidation) fail and that replaying representations of previous experiences seems required for solving this scenario.


Exact Rate-Distortion in Autoencoders via Echo Noise

arXiv.org Machine Learning

Compression is at the heart of effective representation learning. However, lossy compression is typically achieved through simple parametric models like Gaussian noise to preserve analytic tractability, and the limitations this imposes on learning are largely unexplored. Further, the Gaussian prior assumptions in models such as variational autoencoders (VAEs) provide only an upper bound on the compression rate in general. We introduce a new noise channel, Echo noise, that admits a simple, exact expression for mutual information for arbitrary input distributions. The noise is constructed in a data-driven fashion that does not require restrictive distributional assumptions. With its complex encoding mechanism and exact rate regularization, Echo leads to improved bounds on log-likelihood and dominates $\beta$-VAEs across the achievable range of rate-distortion trade-offs. Further, we show that Echo noise can outperform state-of-the-art flow methods without the need to train complex distributional transformations


How Widely Can Prediction Models be Generalized? An Analysis of Performance Prediction in Blended Courses

arXiv.org Machine Learning

Blended courses that mix in-person instruction with online platforms are increasingly popular in secondary education. These tools record a rich amount of data on students' study habits and social interactions. Prior research has shown that these metrics are correlated with students' performance in face to face classes. However, predictive models for blended courses are still limited and have not yet succeeded at early prediction or cross-class predictions even for repeated offerings of the same course. In this work, we use data from two offerings of two different undergraduate courses to train and evaluate predictive models on student performance based upon persistent student characteristics including study habits and social interactions. We analyze the performance of these models on the same offering, on different offerings of the same course, and across courses to see how well they generalize. We also evaluate the models on different segments of the courses to determine how early reliable predictions can be made. This work tells us in part how much data is required to make robust predictions and how cross-class data may be used, or not, to boost model performance. The results of this study will help us better understand how similar the study habits, social activities, and the teamwork styles are across semesters for students in each performance category. These trained models also provide an avenue to improve our existing support platforms to better support struggling students early in the semester with the goal of providing timely intervention.


Modified online Newton step based on element wise multiplication

arXiv.org Machine Learning

The second order method as Newton Step is a suitable technique in Online Learning to guarantee regret bound. The large data is a challenge in Newton method to store second order matrices as hessian. In this paper, we have proposed an modified online Newton step that store first and second order matrices of dimension m (classes) by d (features). we have used element wise arithmetic operation to retain matrices size same. The modified second order matrix size results in faster computations. Also, the mistake rate is at par with respect to popular methods in literature. The experiments outcome indicate that proposed method could be helpful to handle large multi class datasets in common desktop machines using second order method as Newton step.


Improving interactive reinforcement learning: What makes a good teacher?

arXiv.org Artificial Intelligence

Interactive reinforcement learning has become an important apprenticeship approach to speed up convergence in classic reinforcement learning problems. In this regard, a variant of interactive reinforcement learning is policy shaping which uses a parent-like trainer to propose the next action to be performed and by doing so reduces the search space by advice. On some occasions, the trainer may be another artificial agent which in turn was trained using reinforcement learning methods to afterward becoming an advisor for other learner-agents. In this work, we analyze internal representations and characteristics of artificial agents to determine which agent may outperform others to become a better trainer-agent. Using a polymath agent, as compared to a specialist agent, an advisor leads to a larger reward and faster convergence of the reward signal and also to a more stable behavior in terms of the state visit frequency of the learner-agents. Moreover, we analyze system interaction parameters in order to determine how influential they are in the apprenticeship process, where the consistency of feedback is much more relevant when dealing with different learner obedience parameters.


Top 5 tech skills data scientists need, and how to learn them

#artificialintelligence

Data scientists remain in high demand, but those interested in pursuing a career in the field must have the right skillset to land a job with a top salary, according to a Thursday report from Indeed Prime. Demand for data science professionals continues to rise as more companies seek to collect and analyze data and draw business insights from that information. Data scientist job postings have increased by 256% since December 2013, and median base salaries have reached $130,000, according to Indeed data. As more companies adopt data-driven approaches, data scientists must keep their skills current based on what employers need, the report noted. Indeed Prime analyzed the most asked-for skills in Indeed job postings.


How To Put Machine Learning To Work For Your Business

#artificialintelligence

Machine learning has been driving innovation in product features for several years, becoming a vital component of enhancing the consumer experience. However, in terms of what machine learning (ML) -- and specifically, artificial intelligence (AI) -- can do, we've only seen the tip of the iceberg. As a business leader, you may feel a bit like Chevy Chase in Fletch trying to flub your way into appearing knowledgeable about machine learning (it's all ball bearings nowadays…). Nevertheless, it's vital to understand what machine learning is and how to get the most out of it for your business. While it sounds technical, machine learning, in the simplest sense, is a branch of artificial intelligence that uses computer algorithms to learn from data and make better predictions.


HAKE: Human Activity Knowledge Engine

arXiv.org Artificial Intelligence

Human activity understanding is crucial for building automatic intelligent system. With the help of deep learning, activity understanding has made huge progress recently. But some challenges such as imbalanced data distribution, action ambiguity, complex visual patterns still remain. To address these and promote the activity understanding, we build a large-scale Human Activity Knowledge Engine (HAKE) based on the human body part states. Upon existing activity datasets, we annotate the part states of all the active persons in all images, thus establish the relationship between instance activity and body part states. Furthermore, we propose a HAKE based part state recognition model with a knowledge extractor named Activity2Vec and a corresponding part state based reasoning network. With HAKE, our method can alleviate the learning difficulty brought by the long-tail data distribution, and bring in interpretability. Now our HAKE has more than 7 M+ part state annotations and is still under construction. We first validate our approach on a part of HAKE in this preliminary paper, where we show 7.2 mAP performance improvement on Human-Object Interaction recognition, and 12.38 mAP improvement on the one-shot subsets.


The NASA Twins Study: A multidimensional analysis of a year-long human spaceflight

Science

Space is the final frontier for understanding how extreme environments affect human physiology. Following twin astronauts, one of which spent a year-long mission on the International Space Station, Garrett-Bakelman et al. examined molecular and physiological traits that may be affected by time in space (see the Perspective by Löbrich and Jeggo). Sequencing the components of whole blood revealed that the length of telomeres, which is important to maintain in dividing cells and may be related to human aging, changed substantially during space flight and again upon return to Earth. Coupled with changes in DNA methylation in immune cells and cardiovascular and cognitive effects, this study provides a basis to assess the hazards of long-term space habitation. Science, this issue p. eaau8650; see also p. 127 To date, 559 humans have been flown into space, but long-duration ( 300 days) missions are rare (n 8 total). Long-duration missions that will take humans to Mars and beyond are planned ...


How to accelerate DevOps with Machine Learning lifecycle management

#artificialintelligence

DevOps is the union of people, processes, and products to enable the continuous delivery of value to end users. DevOps for machine learning is about bringing the lifecycle management of DevOps to Machine Learning. Utilizing Machine Learning, DevOps can easily manage, monitor, and version models while simplifying workflows and the collaboration process. Effectively managing the Machine Learning lifecycle is critical for DevOps' success. And the first piece to machine learning lifecycle management is building your machine learning pipeline(s).