Africa
GAN-Based Interactive Reinforcement Learning from Demonstration and Human Evaluative Feedback
Huang, Jie, Juan, Rongshun, Gomez, Randy, Nakamura, Keisuke, Sha, Qixin, He, Bo, Li, Guangliang
Deep reinforcement learning (DRL) has achieved great successes in many simulated tasks. The sample inefficiency problem makes applying traditional DRL methods to real-world robots a great challenge. Generative Adversarial Imitation Learning (GAIL) -- a general model-free imitation learning method, allows robots to directly learn policies from expert trajectories in large environments. However, GAIL shares the limitation of other imitation learning methods that they can seldom surpass the performance of demonstrations. In this paper, to address the limit of GAIL, we propose GAN-Based Interactive Reinforcement Learning (GAIRL) from demonstration and human evaluative feedback by combining the advantages of GAIL and interactive reinforcement learning. We tested our proposed method in six physics-based control tasks, ranging from simple low-dimensional control tasks -- Cart Pole and Mountain Car, to difficult high-dimensional tasks -- Inverted Double Pendulum, Lunar Lander, Hopper and HalfCheetah. Our results suggest that with both optimal and suboptimal demonstrations, a GAIRL agent can always learn a more stable policy with optimal or close to optimal performance, while the performance of the GAIL agent is upper bounded by the performance of demonstrations or even worse than it. In addition, our results indicate the reason that GAIRL is superior over GAIL is the complementary effect of demonstrations and human evaluative feedback.
Creepy webcam is shaped just like a human eye
Engineers have created a creepy prototype webcam shaped just like the human eye, called the Eyecam. Inspired by animatronics, Eyecam attaches to the front of a computer monitor and looks left and right โ and even blinks โ while tracking the face of each individual during a video call. At first glance, it looks scarily realistic, right down to the wrinkles in the skin, the individual hairs that make up the eyebrows and the red vessels over the white of the eye. Eyecam โ which is comprised of motors surrounded by 3D-printed silicone โ is open source, meaning you could create your own version at home. Most webcams are too small to be seen - but it's unlikely you'll have the same problem with Eyecam, which has been created because'eyes are crucial for communication' Comedian Lewis Spears discovers Prince Philip's death live on-stage St. Vincent PM: Vaccinated cruise ship passengers evacuated first Eyecam has been created by Marc Teyssier and his team at the Human-Computer Interaction Lab at Saarland University, Germany.
Scientists have translated the structure of a web into music
Scientists in the US have brought the structure of a spider web to life by translating it into music โ a technique that could help us communicate with spiders, they say. They assigned different frequencies of sound to strands of the web, creating'notes' that they combined in patterns, based on the web's 3D structure, to generate melodies. The eerie piece of music, which lasts just over a minute, sounds like the soundtrack for an eerie dystopian sci-fi horror film. It was created by researchers at Massachusetts Institute of Technology (MIT) with laser scanning technology and image processing tools. The experts say spider webs could provide a new source for musical inspiration and provide a form of cross-species communication.
Towards a parallel corpus of Portuguese and the Bantu language Emakhuwa of Mozambique
Ali, Felermino D. M. A., Caines, Andrew, Malavi, Jaimito L. A.
Major advancement in the performance of machine translation models has been made possible in part thanks to the availability of large-scale parallel corpora. But for most languages in the world, the existence of such corpora is rare. Emakhuwa, a language spoken in Mozambique, is like most African languages low-resource in NLP terms. It lacks both computational and linguistic resources and, to the best of our knowledge, few parallel corpora including Emakhuwa already exist. In this paper we describe the creation of the Emakhuwa-Portuguese parallel corpus, which is a collection of texts from the Jehovah's Witness website and a variety of other sources including the African Story Book website, the Universal Declaration of Human Rights and Mozambican legal documents. The dataset contains 47,415 sentence pairs, amounting to 699,976 word tokens of Emakhuwa and 877,595 word tokens in Portuguese. After normalization processes which remain to be completed, the corpus will be made freely available for research use.
Macro-Average: Rare Types Are Important Too
Gowda, Thamme, You, Weiqiu, Lignos, Constantine, May, Jonathan
While traditional corpus-level evaluation metrics for machine translation (MT) correlate well with fluency, they struggle to reflect adequacy. Model-based MT metrics trained on segment-level human judgments have emerged as an attractive replacement due to strong correlation results. These models, however, require potentially expensive re-training for new domains and languages. Furthermore, their decisions are inherently non-transparent and appear to reflect unwelcome biases. We explore the simple type-based classifier metric, MacroF1, and study its applicability to MT evaluation. We find that MacroF1 is competitive on direct assessment, and outperforms others in indicating downstream cross-lingual information retrieval task performance. Further, we show that MacroF1 can be used to effectively compare supervised and unsupervised neural machine translation, and reveal significant qualitative differences in the methods' outputs.
Unsupervised Lane-Change Identification for On-Ramp Merge Analysis in Naturalistic Driving Data
Klitzke, Lars, Gimm, Kay, Koch, Carsten, Kรถster, Frank
Connected and Automated Vehicles (CAVs) are envisioned to transform the future industrial and private transportation sectors. Due to the complexity of the systems, functional verification and validation of safety aspects are essential before the technology merges into the public domain. In recent years, a scenario-driven approach has gained acceptance for CAVs emphasizing the requirement of a solid data basis of scenarios. The large-scale research facility Test Bed Lower Saxony (TFNDS) enables the provision of substantial information for a database of scenarios on motorways. For that purpose, however, the scenarios of interest must be identified and categorized in the collected trajectory data. This work addresses this problem and proposes a framework for on-ramp scenario identification that also enables for scenario categorization and assessment. The efficacy of the framework is shown with a dataset collected on the TFNDS.
Towards Algorithmic Transparency: A Diversity Perspective
Giunchiglia, Fausto, Otterbacher, Jahna, Kleanthous, Styliani, Batsuren, Khuyagbaatar, Bogin, Veronika, Kuflik, Tsvi, Tal, Avital Shulner
As the role of algorithmic systems and processes increases in society, so does the risk of bias, which can result in discrimination against individuals and social groups. Research on algorithmic bias has exploded in recent years, highlighting both the problems of bias, and the potential solutions, in terms of algorithmic transparency (AT). Transparency is important for facilitating fairness management as well as explainability in algorithms; however, the concept of diversity, and its relationship to bias and transparency, has been largely left out of the discussion. We reflect on the relationship between diversity and bias, arguing that diversity drives the need for transparency. Using a perspective-taking lens, which takes diversity as a given, we propose a conceptual framework to characterize the problem and solution spaces of AT, to aid its application in algorithmic systems. Example cases from three research domains are described using our framework.
The World as a Graph: Improving El Ni\~no Forecasts with Graph Neural Networks
Cachay, Salva Rรผhling, Erickson, Emma, Bucker, Arthur Fender C., Pokropek, Ernest, Potosnak, Willa, Bire, Suyash, Osei, Salomey, Lรผtjens, Bjรถrn
Deep learning-based models have recently outperformed state-of-the-art seasonal forecasting models, such as for predicting El Ni\~no-Southern Oscillation (ENSO). However, current deep learning models are based on convolutional neural networks which are difficult to interpret and can fail to model large-scale atmospheric patterns. In comparison, graph neural networks (GNNs) are capable of modeling large-scale spatial dependencies and are more interpretable due to the explicit modeling of information flow through edge connections. We propose the first application of graph neural networks to seasonal forecasting. We design a novel graph connectivity learning module that enables our GNN model to learn large-scale spatial interactions jointly with the actual ENSO forecasting task. Our model, \graphino, outperforms state-of-the-art deep learning-based models for forecasts up to six months ahead. Additionally, we show that our model is more interpretable as it learns sensible connectivity structures that correlate with the ENSO anomaly pattern.
Cross-Lingual Word Embedding Refinement by $\ell_{1}$ Norm Optimisation
Peng, Xutan, Lin, Chenghua, Stevenson, Mark
Cross-Lingual Word Embeddings (CLWEs) encode words from two or more languages in a shared high-dimensional space in which vectors representing words with similar meaning (regardless of language) are closely located. Existing methods for building high-quality CLWEs learn mappings that minimise the $\ell_{2}$ norm loss function. However, this optimisation objective has been demonstrated to be sensitive to outliers. Based on the more robust Manhattan norm (aka. $\ell_{1}$ norm) goodness-of-fit criterion, this paper proposes a simple post-processing step to improve CLWEs. An advantage of this approach is that it is fully agnostic to the training process of the original CLWEs and can therefore be applied widely. Extensive experiments are performed involving ten diverse languages and embeddings trained on different corpora. Evaluation results based on bilingual lexicon induction and cross-lingual transfer for natural language inference tasks show that the $\ell_{1}$ refinement substantially outperforms four state-of-the-art baselines in both supervised and unsupervised settings. It is therefore recommended that this strategy be adopted as a standard for CLWE methods.
Rank-R FNN: A Tensor-Based Learning Model for High-Order Data Classification
Makantasis, Konstantinos, Georgogiannis, Alexandros, Voulodimos, Athanasios, Georgoulas, Ioannis, Doulamis, Anastasios, Doulamis, Nikolaos
An increasing number of emerging applications in data science and engineering are based on multidimensional and structurally rich data. The irregularities, however, of high-dimensional data often compromise the effectiveness of standard machine learning algorithms. We hereby propose the Rank-R Feedforward Neural Network (FNN), a tensor-based nonlinear learning model that imposes Canonical/Polyadic decomposition on its parameters, thereby offering two core advantages compared to typical machine learning methods. First, it handles inputs as multilinear arrays, bypassing the need for vectorization, and can thus fully exploit the structural information along every data dimension. Moreover, the number of the model's trainable parameters is substantially reduced, making it very efficient for small sample setting problems. We establish the universal approximation and learnability properties of Rank-R FNN, and we validate its performance on real-world hyperspectral datasets. Experimental evaluations show that Rank-R FNN is a computationally inexpensive alternative of ordinary FNN that achieves state-of-the-art performance on higher-order tensor data.