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AIs that learn from photos become sexist

Daily Mail - Science & tech

Image recognition AIs that have been trained by some of the most-used research-photo collections are developing sexist biases, according to a new study. University of Virginia computer science professor Vicente Ordóñez and colleagues tested two of the largest collections of photos and data used to train these types of AIs (including one supported by Facebook and Microsoft) and discovered that sexism was rampant. He began the research after noticing a disturbing pattern of sexism in the guesses made by the image recognition software he was building. 'It would see a picture of a kitchen and more often than not associate it with women, not men,' Ordóñez told Wired, adding it also linked women with images of shopping, washing, and even kitchen objects like forks. The AI was also associating men with stereotypically masculine activities like sports, hunting, and coaching, as well as objects sch as sporting equipment.


Stacked transfer learning for tropical cyclone intensity prediction

arXiv.org Machine Learning

Tropical cyclone wind-intensity prediction is a challenging task considering drastic changes climate patterns over the last few decades. In order to develop robust prediction models, one needs to consider different characteristics of cyclones in terms of spatial and temporal characteristics. Transfer learning incorporates knowledge from a related source dataset to compliment a target datasets especially in cases where there is lack or data. Stacking is a form of ensemble learning focused for improving generalization that has been recently used for transfer learning problems which is referred to as transfer stacking. In this paper, we employ transfer stacking as a means of studying the effects of cyclones whereby we evaluate if cyclones in different geographic locations can be helpful for improving generalization performance. Moreover, we use conventional neural networks for evaluating the effects of duration on cyclones in prediction performance. Therefore, we develop an effective strategy that evaluates the relationships between different types of cyclones through transfer learning and conventional learning methods via neural networks.


Dynamic Input Structure and Network Assembly for Few-Shot Learning

arXiv.org Machine Learning

The ability to learn from a small number of examples has been a difficult problem in machine learning since its inception. While methods have succeeded with large amounts of training data, research has been underway in how to accomplish similar performance with fewer examples, known as one-shot or more generally few-shot learning. This technique has been shown to have promising performance, but in practice requires fixed-size inputs making it impractical for production systems where class sizes can vary. This impedes training and the final utility of few-shot learning systems. This paper describes an approach to constructing and training a network that can handle arbitrary example sizes dynamically as the system is used.


A Deterministic Nonsmooth Frank Wolfe Algorithm with Coreset Guarantees

arXiv.org Machine Learning

We present a new Frank-Wolfe (FW) type algorithm that is applicable to minimization problems with a nonsmooth convex objective. We provide convergence bounds and show that the scheme yields so-called coreset results for various Machine Learning problems including 1-median, Balanced Development, Sparse PCA, Graph Cuts, and the $\ell_1$-norm-regularized Support Vector Machine (SVM) among others. This means that the algorithm provides approximate solutions to these problems in time complexity bounds that are not dependent on the size of the input problem. Our framework, motivated by a growing body of work on sublinear algorithms for various data analysis problems, is entirely deterministic and makes no use of smoothing or proximal operators. Apart from these theoretical results, we show experimentally that the algorithm is very practical and in some cases also offers significant computational advantages on large problem instances. We provide an open source implementation that can be adapted for other problems that fit the overall structure.


Matrix Completion from $O(n)$ Samples in Linear Time

arXiv.org Machine Learning

We consider the problem of reconstructing a rank-$k$ $n \times n$ matrix $M$ from a sampling of its entries. Under a certain incoherence assumption on $M$ and for the case when both the rank and the condition number of $M$ are bounded, it was shown in \cite{CandesRecht2009, CandesTao2010, keshavan2010, Recht2011, Jain2012, Hardt2014} that $M$ can be recovered exactly or approximately (depending on some trade-off between accuracy and computational complexity) using $O(n \, \text{poly}(\log n))$ samples in super-linear time $O(n^{a} \, \text{poly}(\log n))$ for some constant $a \geq 1$. In this paper, we propose a new matrix completion algorithm using a novel sampling scheme based on a union of independent sparse random regular bipartite graphs. We show that under the same conditions w.h.p. our algorithm recovers an $\epsilon$-approximation of $M$ in terms of the Frobenius norm using $O(n \log^2(1/\epsilon))$ samples and in linear time $O(n \log^2(1/\epsilon))$. This provides the best known bounds both on the sample complexity and computational complexity for reconstructing (approximately) an unknown low-rank matrix. The novelty of our algorithm is two new steps of thresholding singular values and rescaling singular vectors in the application of the "vanilla" alternating minimization algorithm. The structure of sparse random regular graphs is used heavily for controlling the impact of these regularization steps.


Prototypal Analysis and Prototypal Regression

arXiv.org Machine Learning

Prototypal analysis is introduced to overcome two shortcomings of archetypal analysis: its sensitivity to outliers and its non-locality, which reduces its applicability as a learning tool. Same as archetypal analysis, prototypal analysis finds prototypes through convex combination of the data points and approximates the data through convex combination of the archetypes, but it adds a penalty for using prototypes distant from the data points for their reconstruction. Prototypal analysis can be extended---via kernel embedding---to probability distributions, since the convexity of the prototypes makes them interpretable as mixtures. Finally, prototypal regression is developed, a robust supervised procedure which allows the use of distributions as either features or labels.


On the Safety of Machine Learning: Cyber-Physical Systems, Decision Sciences, and Data Products

arXiv.org Machine Learning

Machine learning algorithms increasingly influence our decisions and interact with us in all parts of our daily lives. Therefore, just as we consider the safety of power plants, highways, and a variety of other engineered socio-technical systems, we must also take into account the safety of systems involving machine learning. Heretofore, the definition of safety has not been formalized in a machine learning context. In this paper, we do so by defining machine learning safety in terms of risk, epistemic uncertainty, and the harm incurred by unwanted outcomes. We then use this definition to examine safety in all sorts of applications in cyber-physical systems, decision sciences, and data products. We find that the foundational principle of modern statistical machine learning, empirical risk minimization, is not always a sufficient objective. Finally, we discuss how four different categories of strategies for achieving safety in engineering, including inherently safe design, safety reserves, safe fail, and procedural safeguards can be mapped to a machine learning context. We then discuss example techniques that can be adopted in each category, such as considering interpretability and causality of predictive models, objective functions beyond expected prediction accuracy, human involvement for labeling difficult or rare examples, and user experience design of software and open data.


Flexible Low-Rank Statistical Modeling with Side Information

arXiv.org Machine Learning

We propose a general framework for reduced-rank modeling of matrix-valued data. By applying a generalized nuclear norm penalty we can directly model low-dimensional latent variables associated with rows and columns. Our framework flexibly incorporates row and column features, smoothing kernels, and other sources of side information by penalizing deviations from the row and column models. Moreover, a large class of these models can be estimated scalably using convex optimization. The computational bottleneck in each case is one singular value decomposition per iteration of a large but easy-to-apply matrix. Our framework generalizes traditional convex matrix completion and multi-task learning methods as well as maximum a posteriori estimation under a large class of popular hierarchical Bayesian models.


Tesla's gigafactory revealed in latest drone footage

Daily Mail - Science & tech

New drone footage has revealed the latest look of Tesla's Gigafactory located on Electric Avenue in Sparks, Nevada. Once completed in 2020, the factory is set to become one of the biggest buildings in the world, with a final size of 10 million square feet. With production underway at the Gigafactory, the company is churning out lithium ion battery cells by the masses in hopes to ultimately reduce the cost of sustainable energy. Tesla says the factory will be producing 35 gigawatt hours of batteries by 2018, which is crucial for the company in reaching its production target of 10,000 units per week in 2018 for its new Model 3 car. According to electrek, Tesla's goal is on target as Tesla co-founder Elon Musk said this month that the factory is already the biggest battery producing factory in the world.


Incredible heart-shaped cell entangled in a blood clot

Daily Mail - Science & tech

This astounding photo of a heart-shaped cell entangled in a blood clot has won the British Hearth Foundation's 2017 photo contest. In the image, which was captured through an electron microscope, red blood cells are trapped in the 3D mesh of fibrin fibres, which hold the clot together. The cell had remarkably been compressed into a heart shape by the contracting fibres surrounding it. Taken by Fraser Macrae, a BHF-funded researcher at the University of Leeds, this image shows a heart-shaped cell entangled in a blood clot held together by a mesh of fibrin fibres. Taken at 5,000-times magnification, this image shows a heart-shaped cell entangled in a blood clot.