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The foundations of machine learning in mid-sized organisations

#artificialintelligence

As global firms with deep pockets invest in machine learning and launch new AI-backed products, services and processes, how should mid-sized organisations with less time and technical expertise respond? Up to now most have chosen to wait and see. But many who have invested have achieved results which show that across industries and company sizes machine learning solutions can slice cost from internal business processes and inspire new product and service possibilities. We've seen voice and image recognition come of age, mapping platforms identify traffic delays and recommend new routes in near real-time and e-commerce platforms find and cluster similar products helping customer find what they need and what they didn't know they needed. For mid-sized organisations, machine learning can lower costs or opens up new markets by offsetting the scale advantages available to larger organisations, and much more.


Interpretation of Natural Language Rules in Conversational Machine Reading

arXiv.org Machine Learning

Most work in machine reading focuses on question answering problems where the answer is directly expressed in the text to read. However, many real-world question answering problems require the reading of text not because it contains the literal answer, but because it contains a recipe to derive an answer together with the reader's background knowledge. One example is the task of interpreting regulations to answer "Can I...?" or "Do I have to...?" questions such as "I am working in Canada. Do I have to carry on paying UK National Insurance?" after reading a UK government website about this topic. This task requires both the interpretation of rules and the application of background knowledge. It is further complicated due to the fact that, in practice, most questions are underspecified, and a human assistant will regularly have to ask clarification questions such as "How long have you been working abroad?" when the answer cannot be directly derived from the question and text. In this paper, we formalise this task and develop a crowd-sourcing strategy to collect 32k task instances based on real-world rules and crowd-generated questions and scenarios. We analyse the challenges of this task and assess its difficulty by evaluating the performance of rule-based and machine-learning baselines. We observe promising results when no background knowledge is necessary, and substantial room for improvement whenever background knowledge is needed.


Elastic bands across the path: A new framework and methods to lower bound DTW

arXiv.org Machine Learning

There has been renewed recent interest in developing effective lower bounds for Dynamic Time Warping (DTW) distance between time series. These have many applications in time series indexing, clustering, forecasting, regression and classification. One of the key time series classification algorithms, the nearest neighbor algorithm with DTW distance (NN-DTW) is very expensive to compute, due to the quadratic complexity of DTW. Lower bound search can speed up NN-DTW substantially. An effective and tight lower bound quickly prunes off unpromising nearest neighbor candidates from the search space and minimises the number of the costly DTW computations. The speed up provided by lower bound search becomes increasingly critical as training set size increases. Different lower bounds provide different trade-offs between computation time and tightness. Most existing lower bounds interact with DTW warping window sizes. They are very tight and effective at smaller warping window sizes, but become looser as the warping window increases, thus reducing the pruning effectiveness for NN-DTW. In this work, we present a new class of lower bounds that are tighter than the popular Keogh lower bound, while requiring similar computation time. Our new lower bounds take advantage of the DTW boundary condition, monotonicity and continuity constraints to create a tighter lower bound. Of particular significance, they remain relatively tight even for large windows. A single parameter to these new lower bounds controls the speed-tightness trade-off. We demonstrate that these new lower bounds provide an exceptional balance between computation time and tightness for the NN-DTW time series classification task, resulting in greatly improved efficiency for NN-DTW lower bound search.


The Disparate Effects of Strategic Manipulation

arXiv.org Machine Learning

When consequential decisions are informed by algorithmic input, individuals may feel compelled to alter their behavior in order to gain a system's approval. Previous models of agent responsiveness, termed "strategic manipulation," have analyzed the interaction between a learner and agents in a world where all agents are equally able to manipulate their features in an attempt to "trick" a published classifier. In cases of real world classification, however, an agent's ability to adapt to an algorithm, is not simply a function of her personal interest in receiving a positive classification, but is bound up in a complex web of social factors that affect her ability to pursue certain action responses. In this paper, we adapt models of strategic manipulation to better capture dynamics that may arise in a setting of social inequality wherein candidate groups face different costs to manipulation. We find that whenever one group's costs are higher than the other's, the learner's equilibrium strategy exhibits an inequality-reinforcing phenomenon wherein the learner erroneously admits some members of the advantaged group, while erroneously excluding some members of the disadvantaged group. We also consider the effects of potential interventions in which a learner can subsidize members of the disadvantaged group, lowering their costs in order to improve her own classification performance. Here we encounter a paradoxical result: there exist cases in which providing a subsidy improves only the learner's utility while actually making both candidate groups worse-off--even the group receiving the subsidy. Our results reveal the potentially adverse social ramifications of deploying tools that attempt to evaluate an individual's "quality" when agents' capacities to adaptively respond differ.


Making \emph{ordinary least squares} linear classfiers more robust

arXiv.org Machine Learning

In the field of statistics and machine learning, the sums-of-squares, commonly referred to as \emph{ordinary least squares}, can be used as a convenient choice of cost function because of its many nice analytical properties, though not always the best choice. However, it has been long known that \emph{ordinary least squares} is not robust to outliers. Several attempts to resolve this problem led to the creation of alternative methods that, either did not fully resolved the \emph{outlier problem} or were computationally difficult. In this paper, we provide a very simple solution that can make \emph{ordinary least squares} less sensitive to outliers in data classification, by \emph{scaling the augmented input vector by its length}. We show some mathematical expositions of the \emph{outlier problem} using some approximations and geometrical techniques. We present numerical results to support the efficacy of our method.


What Makes Reading Comprehension Questions Easier?

arXiv.org Artificial Intelligence

A challenge in creating a dataset for machine reading comprehension (MRC) is to collect questions that require a sophisticated understanding of language to answer beyond using superficial cues. In this work, we investigate what makes questions easier across recent 12 MRC datasets with three question styles (answer extraction, description, and multiple choice). We propose to employ simple heuristics to split each dataset into easy and hard subsets and examine the performance of two baseline models for each of the subsets. We then manually annotate questions sampled from each subset with both validity and requisite reasoning skills to investigate which skills explain the difference between easy and hard questions. From this study, we observed that (i) the baseline performances for the hard subsets remarkably degrade compared to those of entire datasets, (ii) hard questions require knowledge inference and multiple-sentence reasoning in comparison with easy questions, and (iii) multiple-choice questions tend to require a broader range of reasoning skills than answer extraction and description questions. These results suggest that one might overestimate recent advances in MRC.


Experts warn kids who play video games for hours are at risk of developing deadly medical conditions

Daily Mail - Science & tech

Children who spend hours playing video games could be at risk of developing a potentially deadly medical condition called deep vein thrombosis, experts warn. Deep vein thrombosis (DVT) is a blood clot that forms in the veins of one's legs - and the risks of getting DVT are higher if you sit still or lie down for extended periods of time without moving. While DVT is more common among the elderly, new research from the Medical Research Institute of New Zealand shows that it can also be triggered in young children who live sedentary lifestyles. This is why children who play video games - whether they're sitting or lying down - for up to three hours or more could potentially develop deep vein thrombosis. In one case, a boy as young as 12 suffered from DVT after he played video games for four hours straight in a kneeling position, The Telegraph reported.


Facial recognition airport: System makes immediate impact in US

#artificialintelligence

After just three days using its new cutting-edge facial comparison biometric system, US customs intercepted an imposter posing as a French citizen trying to enter America. The 26-year-old man who was travelling from Sao Paulo, Brazil, last week became the first person to be caught out by the new technology, which is currently being tested at 14 international US airports. After the system alerted to a facial discrepancy, a search of the passenger revealed the man had concealed a Republic of Congo identification card in his shoe. He was deported without charge. US Customs and Border Protection hope the facial recognition software will detect terrorists and criminals before they can enter the US.


Zero-shot Transfer Learning for Semantic Parsing

arXiv.org Machine Learning

While neural networks have shown impressive performance on large datasets, applying these models to tasks where little data is available remains a challenging problem. In this paper we propose to use feature transfer in a zero-shot experimental setting on the task of semantic parsing. We first introduce a new method for learning the shared space between multiple domains based on the prediction of the domain label for each example. Our experiments support the superiority of this method in a zero-shot experimental setting in terms of accuracy metrics compared to state-of-the-art techniques. In the second part of this paper we study the impact of individual domains and examples on semantic parsing performance. We use influence functions to this aim and investigate the sensitivity of domain-label classification loss on each example. Our findings reveal that cross-domain adversarial attacks identify useful examples for training even from the domains the least similar to the target domain. Augmenting our training data with these influential examples further boosts our accuracy at both the token and the sequence level.


Benchmarking Single Image Dehazing and Beyond

arXiv.org Artificial Intelligence

Abstract--We present a comprehensive study and evaluation of existing single image dehazing algorithms, using a new largescale benchmark consisting of both synthetic and real-world hazy images, called REalistic Single Image DEhazing (RESIDE). RESIDE highlights diverse data sources and image contents, and is divided into five subsets, each serving different training or evaluation purposes. We further provide a rich variety of criteria for dehazing algorithm evaluation, ranging from full-reference metrics, to no-reference metrics, to subjective evaluation and the novel task-driven evaluation. Experiments on RESIDE shed light on the comparisons and limitations of state-of-the-art dehazing algorithms, and suggest promising future directions. A. Problem Description: Single Image Dehazing Images captured in outdoor scenes often suffer from poor visibility, reduced contrasts, fainted surfaces and color shift, due to the presence of haze. Caused by aerosols such as dust, mist, and fumes, the existence of haze adds complicated, nonlinear and data-dependent noise to the images, making the haze removal (a.k.a. Moreover, many computer vision algorithms can only work well with the scene radiance that is haze-free. However, a dependable vision system must reckon with the entire spectrum of degradations from unconstrained environments. Taking autonomous driving for example, hazy and foggy weather will obscure the vision of on-board cameras and create confusing reflections and glare, leaving state-of-the-art self-driving cars in struggle [1]. Boyi Li is with the Computer Science Department, Cornell University, USA.