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On the interaction between supervision and self-play in emergent communication

arXiv.org Machine Learning

A promising approach for teaching artificial agents to use natural language involves using human-in-the-loop training. However, recent work suggests that current machine learning methods are too data inefficient to be trained in this way from scratch. In this paper, we investigate the relationship between two categories of learning signals with the ultimate goal of improving sample efficiency: imitating human language data via supervised learning, and maximizing reward in a simulated multi-agent environment via self-play (as done in emergent communication), and introduce the term supervised self-play (S2P) for algorithms using both of these signals. We find that first training agents via supervised learning on human data followed by self-play outperforms the converse, suggesting that it is not beneficial to emerge languages from scratch. We then empirically investigate various S2P schedules that begin with supervised learning in two environments: a Lewis signaling game with symbolic inputs, and an image-based referential game with natural language descriptions. Lastly, we introduce population based approaches to S2P, which further improves the performance over single-agent methods.


The exponentially weighted average forecaster in geodesic spaces of non-positive curvature

arXiv.org Machine Learning

The problem of prediction with expert advice [ Cesa-Bianchi and Lugosi, 2006 ] is a by now standard model of online learning. Traditionally studied for outcom es taking values in a vector space, less seems to be known when the outcome space is a more general metr ic space. This paper partly addresses the problem by focusing on the case of NPC spaces, i .e., geodesic metric spaces with non-positive curvature in the sense of Alexandrov. The class of NPC spaces includes many metric spaces of partic ular interest in the data sciences. Apart from Hilbert spaces, interesting examples are hyperb olic spaces [ Nickel and Kiela, 2017 ], the space of real symmetric positive-definite matrices with Log -Euclidean [ Arsigny et al., 2007 ] or Log-Cholesky [ Lin, 2019 ] Riemannian metrics and more generally all complete and sim ply connected Riemannian manifolds with non-positive sectional curvatu re.


Evolutionary algorithms for constructing an ensemble of decision trees

arXiv.org Machine Learning

Most decision tree induction algorithms are based on a greedy top-down recursive partitioning strategy for tree growth. In this paper, we propose several methods for induction of decision trees and their ensembles based on evolutionary algorithms. The main difference of our approach is using real-valued vector representation of decision tree that allows to use a large number of different optimization algorithms, as well as optimize the whole tree or ensemble for avoiding local optima. Differential evolution and evolution strategies were chosen as optimization algorithms, as they have good results in reinforcement learning problems. We test the predictive performance of this methods using several public UCI data sets, and the proposed methods show better quality than classical methods.


Effective Diversity in Population-Based Reinforcement Learning

arXiv.org Machine Learning

Maintaining a population of solutions has been shown to increase exploration in reinforcement learning, typically attributed to the greater diversity of behaviors considered. One such class of methods, novelty search, considers further boosting diversity across agents via a multi-objective optimization formulation. Despite the intuitive appeal, these mechanisms have several shortcomings. First, they make use of mean field updates, which induce cycling behaviors. Second, they often rely on handcrafted behavior characterizations, which require domain knowledge. Furthermore, boosting diversity often has a detrimental impact on optimizing already fruitful behaviors for rewards. Setting the relative importance of novelty- versus reward-factor is usually hardcoded or requires tedious tuning/annealing. In this paper, we introduce a novel measure of population-wide diversity, leveraging ideas from Determinantal Point Processes. We combine this in a principled fashion with the reward function to adapt to the degree of diversity during training, borrowing ideas from online learning. Combined with task-agnostic behavioral embeddings, we show this approach outperforms previous methods for multi-objective optimization, as well as vanilla algorithms solely optimizing for rewards.


Revisiting Meta-Learning as Supervised Learning

arXiv.org Machine Learning

Recent years have witnessed an abundance of new publications and approaches on meta-learning. This community-wide enthusiasm has sparked great insights but has also created a plethora of seemingly different frameworks, which can be hard to compare and evaluate. In this paper, we aim to provide a principled, unifying framework by revisiting and strengthening the connection between meta-learning and traditional supervised learning. By treating pairs of task-specific data sets and target models as (feature, label) samples, we can reduce many meta-learning algorithms to instances of supervised learning. This view not only unifies meta-learning into an intuitive and practical framework but also allows us to transfer insights from supervised learning directly to improve meta-learning. For example, we obtain a better understanding of generalization properties, and we can readily transfer well-understood techniques, such as model ensemble, pre-training, joint training, data augmentation, and even nearest neighbor based methods. We provide an intuitive analogy of these methods in the context of meta-learning and show that they give rise to significant improvements in model performance on few-shot learning.


Python: A-Z Artificial Intelligence with Python: 5-in-1

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Artificial Intelligence is one of the hottest field in computer science at the moment and has taken the world by storm as a major field of development and research. Python has emerged as a dominant language in AI/ML programming because of its simplicity and flexibility. Are you a Python developer who is interested to build real-world Artificial Intelligence applications? If so, A-Z Artificial Intelligence with Python is for you! This comprehensive 5-in-1 training course is designed such that you can add an intelligence layer to any application that's based on images, text, stock market, or some other form of data.


Data Wrangling in Pandas for Machine Learning Engineers

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"The course is really impressive. Tons of information, and I learned a great deal. I had no Python background, and now I feel a lot more confident about working with Python than ever. "Honestly Mike your classes speak for themselves. They're informative, concise and just really well put together.


Keeping personalised learning alive with artificial intelligence

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You know you have a school you can be truly proud of when it is described by one of your pupils to Ofsted inspectors as'like a big family'. That's the special place we've created at Hawkedale for our pupils to learn and grow. Over the last four years, our school has grown too. We've expanded from being a single form infant school with three classes to a primary school welcoming 146 pupils, with a further 30 pupils due to start in September 2020. This is a journey that an increasing number of schools will undertake.


Machine Learning Course with SAS, Free Trial

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Get seven free days to experience our Machine Learning With SAS Viya course. Learn the theoretical foundation for different techniques associated with supervised machine learning models. You'll develop a series of supervised learning models, including decision tree, ensemble of trees (forest and gradient boosting), neural networks and support vector machines.


Machine Learning with Python was issued by Coursera to Jehudi Castro.

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The badge earner has demonstrated a good understanding and application of machine learning (ML) including when to use different ML techniques such as regression, classification, clustering and recommender systems. The individual has acquired the skills to use different machine learning libraries in Python, mainly Scikit-learn and Scipy, to generate and apply different types of ML algorithms such as decision trees, logistic regression, k-means, KNN, DBSCCAN, SVM and hierarchical clustering.