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Leveraging Unlabeled Data to Predict Out-of-Distribution Performance

arXiv.org Machine Learning

Real-world machine learning deployments are characterized by mismatches between the source (training) and target (test) distributions that may cause performance drops. In this work, we investigate methods for predicting the target domain accuracy using only labeled source data and unlabeled target data. We propose Average Thresholded Confidence (ATC), a practical method that learns a threshold on the model's confidence, predicting accuracy as the fraction of unlabeled examples for which model confidence exceeds that threshold. ATC outperforms previous methods across several model architectures, types of distribution shifts (e.g., due to synthetic corruptions, dataset reproduction, or novel subpopulations), and datasets (W In our experiments, ATC estimates target performance 2-4ˆ more accurately than prior methods. We also explore the theoretical foundations of the problem, proving that, in general, identifying the accuracy is just as hard as identifying the optimal predictor and thus, the efficacy of any method rests upon (perhaps unstated) assumptions on the nature of the shift. Finally, analyzing our method on some toy distributions, we provide insights concerning when it works. Machine learning models deployed in the real world typically encounter examples from previously unseen distributions. While the IID assumption enables us to evaluate models using held-out data from the source distribution (from which training data is sampled), this estimate is no longer valid in presence of a distribution shift. Moreover, under such shifts, model accuracy tends to degrade (Szegedy et al., 2014; Recht et al., 2019; Koh et al., 2021). Commonly, the only data available to the practitioner are a labeled training set (source) and unlabeled deployment-time data which makes the problem more difficult. In this setting, detecting shifts in the distribution of covariates is known to be possible (but difficult) in theory (Ramdas et al., 2015), and in practice (Rabanser et al., 2018). However, producing an optimal predictor using only labeled source and unlabeled target data is well-known to be impossible absent further assumptions (Ben-David et al., 2010; Lipton et al., 2018). Two vital questions that remain are: (i) the precise conditions under which we can estimate a classifier's target-domain accuracy; and (ii) which methods are most practically useful. To begin, the straightforward way to assess the performance of a model under distribution shift would be to collect labeled (target domain) examples and then to evaluate the model on that data. However, collecting fresh labeled data from the target distribution is prohibitively expensive and time-consuming, especially if the target distribution is non-stationary.


A Feature Extraction based Model for Hate Speech Identification

arXiv.org Artificial Intelligence

The detection of hate speech online has become an important task, as offensive language such as hurtful, obscene and insulting content can harm marginalized people or groups. This paper presents TU Berlin team experiments and results on the task 1A and 1B of the shared task on hate speech and offensive content identification in Indo-European languages 2021. The success of different Natural Language Processing models is evaluated for the respective subtasks throughout the competition. We tested different models based on recurrent neural networks in word and character levels and transfer learning approaches based on Bert on the provided dataset by the competition. Among the tested models that have been used for the experiments, the transfer learning-based models achieved the best results in both subtasks.


This AI Software Nearly Predicted Omicron's Tricky Structure

WIRED

On November 26, the World Health Organization designated the strain of coronavirus surging in South Africa a "variant of concern" and christened it Omicron. The next day, University of British Columbia professor Sriram Subramaniam downloaded a genome sequence posted online and ordered samples of Omicron DNA to be shipped to his lab. Subramaniam's group uses electron microscopes to reveal the 3D structure of proteins, to better understand how they work. It had already mapped the spike proteins that coronaviruses use to bind and enter human cells for some earlier strains. Describing Omicron's spike protein felt urgent because its DNA differed in ways that might explain the variant's rapid spread.


Black-Box Tuning for Language-Model-as-a-Service

arXiv.org Artificial Intelligence

Extremely large pre-trained language models (PTMs) such as GPT-3 are usually released as a service, allowing users to design task-specific prompts to query the PTMs through some black-box APIs. In such a scenario, which we call Language-Model-as-a-Service (LMaaS), gradients of the PTMs are usually not available. Can we optimize the task prompts by only accessing the model inference APIs? Based on recent observations that large PTMs have a very low intrinsic dimensionality, this work proposes the Black-Box Tuning to optimize PTMs through derivative-free algorithms. In particular, we invoke the CMA-ES to optimize the continuous prompt prepended to the input text by iteratively calling PTM inference APIs. Our experimental results demonstrate that, black-box tuning with RoBERTa on a few labeled samples not only significantly outperforms manual prompt and GPT-3's in-context learning, but also surpasses the gradient-based counterparts, namely prompt tuning and full model tuning.


$5.2 billion #AI deal with a company that uses artificial intelligence to make new medicines. - IO

#artificialintelligence

Sanofi formed a deal to develop 15 experimental oncology and immunology drugs with Exscientia Plc with possible total payouts of as much as $5.2 billion, allying with a company that uses artificial intelligence to make new medicines.Most Read from BloombergOmicron Study in South Africa Points to End of Acute Pandemic PhaseU.S. Check your inbox or spam folder to confirm your subscription.


Hierarchical Graph-Convolutional Variational AutoEncoding for Generative Modelling of Human Motion

arXiv.org Artificial Intelligence

Models of human motion commonly focus either on trajectory prediction or action classification but rarely both. The marked heterogeneity and intricate compositionality of human motion render each task vulnerable to the data degradation and distributional shift common to real-world scenarios. A sufficiently expressive generative model of action could in theory enable data conditioning and distributional resilience within a unified framework applicable to both tasks. Here we propose a novel architecture based on hierarchical variational autoencoders and deep graph convolutional neural networks for generating a holistic model of action over multiple time-scales. We show this Hierarchical Graph-convolutional Variational Autoencoder (HG-VAE) to be capable of generating coherent actions, detecting out-of-distribution data, and imputing missing data by gradient ascent on the model's posterior. Trained and evaluated on H3.6M and the largest collection of open source human motion data, AMASS, we show HG-VAE can facilitate downstream discriminative learning better than baseline models.


10 Best AI Stocks for 2022

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In this article, we discuss the 10 best AI stocks for 2022. If you want to skip our detailed analysis of these stocks, go directly to the 5 Best AI Stocks for 2022. Artificial intelligence is the backbone of a myriad of innovations in today's world such as self-driving cars, high-tech computing, enterprise solutions, and robotics to name a few. AI is also set to play a key role in blockchain technology which forms the basis of the cryptocurrency industry. In addition, AI also played a key role in fighting the spread of COVID-19 from contact tracing to robots and drone deployment to responding to urgent needs in hospitals as well as performing deliveries of food, medications, and equipment.


Google Home, YouTube integrate with Volvo Cars – TechCrunch

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Google unveiled Wednesday at CES 2022 a range of new ways to keep its Android devices connected -- and that includes cars. As more vehicles go electric and automakers evolve into software developers, expect to see more plays directed at turning cars into connected devices. Take Volvo Cars, for instance. The automaker and Google announced at CES 2022 new content and services that will be coming to future Volvo vehicles, including the ability to download and use the YouTube app via Google Play Store and the ability to communicate with the Google Home ecosystem. New Volvo car models are equipped with an Android Automotive operating system and have embedded voice-controlled Google Assistant, Google Play Store, Google Maps and other Google services into its infotainment system.


Knowledge Tracing: A Survey

arXiv.org Artificial Intelligence

Humans ability to transfer knowledge through teaching is one of the essential aspects for human intelligence. A human teacher can track the knowledge of students to customize the teaching on students needs. With the rise of online education platforms, there is a similar need for machines to track the knowledge of students and tailor their learning experience. This is known as the Knowledge Tracing (KT) problem in the literature. Effectively solving the KT problem would unlock the potential of computer-aided education applications such as intelligent tutoring systems, curriculum learning, and learning materials' recommendation. Moreover, from a more general viewpoint, a student may represent any kind of intelligent agents including both human and artificial agents. Thus, the potential of KT can be extended to any machine teaching application scenarios which seek for customizing the learning experience for a student agent (i.e., a machine learning model). In this paper, we provide a comprehensive and systematic review for the KT literature. We cover a broad range of methods starting from the early attempts to the recent state-of-the-art methods using deep learning, while highlighting the theoretical aspects of models and the characteristics of benchmark datasets. Besides these, we shed light on key modelling differences between closely related methods and summarize them in an easy-to-understand format. Finally, we discuss current research gaps in the KT literature and possible future research and application directions.


Artificial Intelligence (AI) in Fintech Market See Huge Growth for New Normal

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Artificial Intelligence (AI) in Fintech Market research is an intelligence report with meticulous efforts undertaken to study the right and valuable information. The data which has been looked upon is done considering both, the existing top players and the upcoming competitors. Business strategies of the key players and the new entering market industries are studied in detail. Well explained SWOT analysis, revenue share and contact information are shared in this report analysis. It also provides market information in terms of development and its capacities.