Goto

Collaborating Authors

 Africa


Certified Robustness to Label-Flipping Attacks via Randomized Smoothing

arXiv.org Machine Learning

Machine learning algorithms are known to be susceptible to data poisoning attacks, where an adversary manipulates the training data to degrade performance of the resulting classifier. While many heuristic defenses have been proposed, few defenses exist which are certified against worst-case corruption of the training data. In this work, we propose a strategy to build linear classifiers that are certifiably robust against a strong variant of label-flipping, where each test example is targeted independently. In other words, for each test point, our classifier makes a prediction and includes a certification that its prediction would be the same had some number of training labels been changed adversarially. Our approach leverages randomized smoothing, a technique that has previously been used to guarantee---with high probability---test-time robustness to adversarial manipulation of the input to a classifier. We derive a variant which provides a deterministic, analytical bound, sidestepping the probabilistic certificates that traditionally result from the sampling subprocedure. Further, we obtain these certified bounds with no additional runtime cost over standard classification. We generalize our results to the multi-class case, providing what we believe to be the first multi-class classification algorithm that is certifiably robust to label-flipping attacks.


Meta-learning framework with applications to zero-shot time-series forecasting

arXiv.org Machine Learning

Can meta-learning discover generic ways of processing time-series (TS) from a diverse dataset so as to greatly improve generalization on new TS coming from different datasets? This work provides positive evidence to demonstrate this using a broad meta-learning framework which we show subsumes many existing meta-learning algorithms as specific cases. We further identify via theoretical analysis the meta-learning adaptation mechanisms within N-BEATS, a recent neural TS forecasting model. Our meta-learning theory predicts that N-BEATS iteratively generates a subset of its task-specific parameters based on a given TS input, thus gradually expanding the expressive power of the architecture on-the-fly. Our empirical results emphasize the importance of meta-learning for successful zero-shot forecasting to new sources of TS, supporting the claim that it is viable to train a neural network on a source TS dataset and deploy it on a different target TS dataset without retraining, resulting in performance that is at least as good as that of state-of-practice univariate forecasting models.


Short sighted deep learning

arXiv.org Machine Learning

A theory explaining how deep learning works is yet to be developed. Previous work suggests that deep learning performs a coarse graining, similar in spirit to the renormalization group (RG). This idea has been explored in the setting of a local (nearest neighbor interactions) Ising spin lattice. We extend the discussion to the setting of a long range spin lattice. Markov Chain Monte Carlo (MCMC) simulations determine both the critical temperature and scaling dimensions of the system. The model is used to train both a single RBM (restricted Boltzmann machine) network, as well as a stacked RBM network. Following earlier Ising model studies, the trained weights of a single layer RBM network define a flow of lattice models. In contrast to results for nearest neighbor Ising, the RBM flow for the long ranged model does not converge to the correct values for the spin and energy scaling dimension. Further, correlation functions between visible and hidden nodes exhibit key differences between the stacked RBM and RG flows. The stacked RBM flow appears to move towards low temperatures whereas the RG flow moves towards high temperature. This again differs from results obtained for nearest neighbor Ising.



On the limits of cross-domain generalization in automated X-ray prediction

arXiv.org Machine Learning

This large scale study focuses on quantifying what X-rays diagnostic prediction tasks generalize well across multiple different datasets. We present evidence that the issue of generalization is not due to a shift in the images but instead a shift in the labels. We study the cross-domain performance, agreement between models, and model representations. We find interesting discrepancies between performance and agreement where models which both achieve good performance disagree in their predictions as well as models which agree yet achieve poor performance. We also test for concept similarity by regularizing a network to group tasks across multiple datasets together and observe variation across the tasks.


End-to-End Models for the Analysis of Pupil Size Variations and Diagnosis of Parkinson's Disease

arXiv.org Machine Learning

It is well known that a systematic analysis of the pupil size variations, recorded by means of an eye-tracker, is a rich source of information about a subject's cognitive state. In this work we present end-to-end models for the diagnosis of Parkinson's disease (PD) based on the raw pupil size signal. Long-range registration (10 minutes) of the pupil size were collected in scotopic conditions (complete darkness, 0 lux) on 21 healthy subjects and 15 subjects diagnosed with PD. 1-D convolutional neural network models are trained for classification of short-range sequences (10 to 60 seconds of registration). The model provides prediction with high average accuracy on a hold out test set. A temporal analysis of the model performance allowed the characterization of pupil's size variations in PD and healthy subjects during a resting state. Dataset and codes are released for reproducibility and benchmarking purposes.


Irony Detection in a Multilingual Context

arXiv.org Artificial Intelligence

This paper proposes the first multilingual (French, English and Arabic) and multicultural (Indo-European languages vs. less culturally close languages) irony detection system. We employ both feature-based models and neural architectures using monolingual word representation. We compare the performance of these systems with state-of-the-art systems to identify their capabilities. We show that these monolingual models trained separately on different languages using multilingual word representation or text-based features can open the door to irony detection in languages that lack of annotated data for irony.


Natural Language Processing (NLP) Market to Reach USD 80.68 billion by 2026; Increasing Demand for Enhanced Algorithms to Boost Growth, says Fortune Business Insights

#artificialintelligence

Key Companies Covered in NLP Market Research Report are 3M Company, Adobe Systems Inc., Amazon Web Services Inc., Apple Inc., Google (Alphabet Inc.), Hewlett-Packard Enterprise Company, Intel Corporation, Microsoft Corporation, SAS Institute Inc., Other key market players The global Natural Language Processing (NLP) Market size is projected to reach USD 80.68 billion by 2026, thereby exhibiting a CAGR of 32.4% during the forecast period. This information is published by Fortune Business Insights, in a report, titled, "Natural Language Processing (NLP) Market Size, Share & Industry Analysis, By Deployment (On-Premises, Cloud, and Hybrid), By Technology (Interactive Voice Response (IVR), Optical Character Recognition (OCR), Text Analytics, Speech Analytics, Classification and Categorization, Pattern and Image Recognition, and Others), By Industry Vertical (Healthcare, Retail, High Tech and Telecom, BFSI, Automotive & Transportation, Advertising & Media, Manufacturing, and Others) and Regional Forecast, 2019-2026." The report further states that the market was USD 8.61 billion in 2018. It is set to gain momentum from the rising demand for big data, improved algorithms, and powerful computing. What Does the Report Contain?


Computer vision algorithm removes the water from underwater images

#artificialintelligence

Underwater photography is hard to get right. Special filters, artificial lights, and top-of-the-line underwater cameras can help, but there's still a lot of water between the camera and the object in the photo. We've become accustomed to the blue-green tint of underwater photography. How would the ocean look without water? What are the true colors of a coral reef?


2020s: The decade artificial intelligence will dominate

#artificialintelligence

Isaac Asimov, roboticist and science fiction writer, predicted in his novel I, Robot in 1950 that robots and artificial intelligence were going to be banned from Earth in the year 2030. Instead, we are seeing huge advances in AI and this is likely to continue within the next decade. The UK's investment in AI recently reached a record high for 2019, rising from $1.02 billion for the whole of 2018 to $1.06 billion in the first six months of 2019. What's more, the European Commission's new president, Ursula von der Leyen recently made calls for a GDPR-style regulation for the use of AI to be put in place, signaling the predicted mass uptake of the technology amongst businesses across different industries. There are multiple facets of AI, all with varied uses and capabilities, and one area in particular that is attracting a lot of attention is Intelligent Automation.