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Hypothesis-based Belief Planning for Dexterous Grasping

arXiv.org Artificial Intelligence

Noname manuscript No. (will be inserted by the editor) Abstract Belief space planning is a viable alternative to formalise partially observable control problems and, in the recent years, its application to robot manipulation problems has grown. However, this planning approach was tried successfully only on simplified control problems. In this paper, we apply belief space planning to the problem of planning dexterous reach-tograsp trajectories under object pose uncertainty. In our framework, the robot perceives the object to be grasped on-the-fly as a point cloud and compute a full 6D, non-Gaussian distribution over the object's pose (our belief space). The system has no limitations on the geometry of the object, i.e., non-convex objects can be represented, nor assumes that the point cloud is a complete Figure 1: Boris: half-humanoid robot platform developed representation of the object. A plan in the belief space at the University of Birmingham. is then created to reach and grasp the object, such that the information value of expected contacts along the trajectory is maximised to compensate for the pose uncertainty. 1 Introduction If an unexpected contact occurs when performing the action, such information is used to refine Imagine that you are reaching into the fridge to grasp the pose distribution and triggers a re-planning. Experimental an object you can only partially see. Rather than relying results show that our planner (IR3ne) improves solely on vision, you must use touch in order to grasp reliability and compensates for the pose uncertainty localise it and securely grasp it.


Adversarial attacks against Fact Extraction and VERification

arXiv.org Artificial Intelligence

This paper describes a baseline for the second iteration of the Fact Extraction and VERification shared task (FEVER2.0) which explores the resilience of systems through adversarial evaluation. We present a collection of simple adversarial attacks against systems that participated in the first FEVER shared task. FEVER modeled the assessment of truthfulness of written claims as a joint information retrieval and natural language inference task using evidence from Wikipedia. A large number of participants made use of deep neural networks in their submissions to the shared task. The extent as to whether such models understand language has been the subject of a number of recent investigations and discussion in literature. In this paper, we present a simple method of generating entailment-preserving and entailment-altering perturbations of instances by common patterns within the training data. We find that a number of systems are greatly affected with absolute losses in classification accuracy of up to $29\%$ on the newly perturbed instances. Using these newly generated instances, we construct a sample submission for the FEVER2.0 shared task. Addressing these types of attacks will aid in building more robust fact-checking models, as well as suggest directions to expand the datasets.


Contextualised concept embedding for efficiently adapting natural language processing models for phenotype identification

arXiv.org Artificial Intelligence

Many efforts have been put to use automated approaches, such as natural language processing (NLP), to mine or extract data from free-text medical records to picture comprehensive patient profiles for delivering better health-care. Reusing NLP models in new settings, however, remains cumbersome - requiring validation and/or retraining on new data iteratively to achieve convergent results. In this paper, we formally define and analyse the NLP model adaptation problem, particularly in phenotype identification tasks, and identify two types of common unnecessary or wasted efforts: duplicate waste and imbalance waste. A distributed representation approach is proposed to represent familiar language patterns for an NLP model by learning phenotype embeddings from its training data. Computations on these language patterns are then introduced to help avoid or reduce unnecessary efforts by combining both geometric and semantic similarities. To evaluate the approach, we cross validate NLP models developed for six physical morbidity studies (23 phenotypes; 17 million documents) on anonymised medical records of South London Maudsley NHS Trust, United Kingdom. Two metrics are introduced to quantify the reductions for both duplicate and imbalance wastes. We conducted various experiments on reusing NLP models in four phenotype identification tasks. Our approach can choose a best model for a given new task, which can identify up to 76% mentions needing no validation & model retraining, meanwhile, having very good performances (93-97% accuracy). It can also provide guidance for validating and retraining the model for novel language patterns in new tasks, which can help save around 80% of the efforts required in blind model-adaptation approaches.


Google must be broken up to save news media, says Rupert Murdoch's News Corp

The Independent - Tech

Google must be broken up to end its "overwhelming" market power and safeguard the world's news media, Rupert Murdoch's News Corp has said. The news organisation's Australian arm demanded an enforced breakup of Google, which dominates online search and advertising businesses. In an 80-page submission to the Australian government, News Corp, which has itself faced allegations of monopolistic behaviour, said Google's search engine and third-party advertising platform should be separated to allow publishers to compete for ad revenues. We'll tell you what's true. You can form your own view.


Interaction Embeddings for Prediction and Explanation in Knowledge Graphs

arXiv.org Artificial Intelligence

Knowledge graph embedding aims to learn distributed representations for entities and relations, and is proven to be effective in many applications. Crossover interactions --- bi-directional effects between entities and relations --- help select related information when predicting a new triple, but haven't been formally discussed before. In this paper, we propose CrossE, a novel knowledge graph embedding which explicitly simulates crossover interactions. It not only learns one general embedding for each entity and relation as most previous methods do, but also generates multiple triple specific embeddings for both of them, named interaction embeddings. We evaluate embeddings on typical link prediction tasks and find that CrossE achieves state-of-the-art results on complex and more challenging datasets. Furthermore, we evaluate embeddings from a new perspective --- giving explanations for predicted triples, which is important for real applications. In this work, an explanation for a triple is regarded as a reliable closed-path between the head and the tail entity. Compared to other baselines, we show experimentally that CrossE, benefiting from interaction embeddings, is more capable of generating reliable explanations to support its predictions.


AI: The tool that sets high-performing sales team apart

#artificialintelligence

For years, sales teams have been inundated with new apps and tools, each promising to help them navigate radical changes in how customers research and buy products. Many sales people are fatigued by tech overload – they're disillusioned by past claims of countless new tools being the next'quick fix', so it's fair that they see artificial intelligence (AI) as yet another tool in their overflowing toolboxes. And, if they listen to some analysts, it's even fair that they fear AI will take their jobs away entirely. But new data from a global study of sales professionals, the third annual State of Sales report, shows AI is being used by high-performers to address major challenges that have been building in the sales profession for years – high-performing sales teams (the top 24 per cent that have significantly increased year-over-year revenue) are nearly five times more likely than underperformers to be using AI. Ai is enabling and helping, rather than replacing, salespeople across the organisation, including inside and outside reps.


How a companion robot can help children with chronic illness

#artificialintelligence

Technological advancements in the medical field are vital to improving the way patients receive care. In many cases, there is a need for more resources to be directed towards patient care. But the current reality for many patients, especially children with chronic illnesses, is that medical professionals and families are often forced to carry a heavy load in caring for them. To address this need within the healthcare sector, there has been an uptick in the size of Australia's medtech startup community, with the NSW government expecting the industry to create 28,000 jobs and add AU$18 billion in gross domestic product to Australia by 2025. Among the medtech startups in Australia is ikkiworks, which developed a companion robot that helps soothe and monitor the vital signs of children with chronic illness while they are away from the hospital.


Fisher-Bures Adversary Graph Convolutional Networks

arXiv.org Machine Learning

In a graph convolutional network, we assume that the graph $G$ is generated with respect to some observation noise. We make small random perturbations $\Delta{}G$ of the graph and try to improve generalization. Based on quantum information geometry, we can have quantitative measurements on the scale of $\Delta{}G$. We try to maximize the intrinsic scale of the permutation with a small budget while minimizing the loss based on the perturbed $G+\Delta{G}$. Our proposed model can consistently improve graph convolutional networks on semi-supervised node classification tasks with reasonable computational overhead. We present two different types of geometry on the manifold of graphs: one is for measuring the intrinsic change of a graph; the other is for measuring how such changes can affect externally a graph neural network. These new analytical tools will be useful in developing a good understanding of graph neural networks and fostering new techniques.


Bayesian Allocation Model: Inference by Sequential Monte Carlo for Nonnegative Tensor Factorizations and Topic Models using Polya Urns

arXiv.org Machine Learning

We introduce a dynamic generative model, Bayesian allocation model (BAM), which establishes explicit connections between nonnegative tensor factorization (NTF), graphical models of discrete probability distributions and their Bayesian extensions, and the topic models such as the latent Dirichlet allocation. BAM is based on a Poisson process, whose events are marked by using a Bayesian network, where the conditional probability tables of this network are then integrated out analytically. We show that the resulting marginal process turns out to be a Polya urn, an integer valued self-reinforcing process. This urn processes, which we name a Polya-Bayes process, obey certain conditional independence properties that provide further insight about the nature of NTF. These insights also let us develop space efficient simulation algorithms that respect the potential sparsity of data: we propose a class of sequential importance sampling algorithms for computing NTF and approximating their marginal likelihood, which would be useful for model selection. The resulting methods can also be viewed as a model scoring method for topic models and discrete Bayesian networks with hidden variables. The new algorithms have favourable properties in the sparse data regime when contrasted with variational algorithms that become more accurate when the total sum of the elements of the observed tensor goes to infinity. We illustrate the performance on several examples and numerically study the behaviour of the algorithms for various data regimes.


Sparse Grouped Gaussian Processes for Solar Power Forecasting

arXiv.org Machine Learning

We consider multi-task regression models where observations are assumed to be a linear combination of several latent node and weight functions, all drawn from Gaussian process priors that allow nonzero covariance between grouped latent functions. Motivated by the problem of developing scalable methods for distributed solar forecasting, we exploit sparse covariance structures where latent functions are assumed to be conditionally independent given a group-pivot latent function. We exploit properties of multivariate Gaussians to construct sparse Cholesky factors directly, rather than obtaining them through iterative routines, and by doing so achieve significantly improved time and memory complexity including prediction complexity that is linear in the number of grouped functions. We test our approach on large multi-task datasets and find that sparse specifications achieve the same or better accuracy than non-sparse counterparts in less time, and improve on benchmark model accuracy.