Oceania
AAAI News
Hamilton, Carol (Association for the Advancement of Artificial Intelligence)
Submissions for HCOMP-19 Are Due in June! The Seventh AAAI Conference on Human Computation and Crowdsourcing (HCOMP 2019) will be held October 28-30 at Skamania Lodge in Washington State near the Columbia Gorge River, just 45 minutes from Portland, Oregon. This year is the 10-year anniversary of the very first HCOMP workshop in Paris, and to celebrate, there will be special events, talks, and panels throughout the conference. HCOMP is the premier venue for disseminating the latest research findings on crowdsourcing and human computation. While artificial intelligence (AI) and human-computer interaction (HCI) represent traditional mainstays of the conference, HCOMP believes strongly in inviting, fostering, and promoting broad, interdisciplinary research.
A Categorisation of Post-hoc Explanations for Predictive Models
Mitros, John, Mac Namee, Brian
The ubiquity of machine learning based predictive models in modern society naturally leads people to ask how trustworthy those models are? In predictive modeling, it is quite common to induce a trade-off between accuracy and interpretability. For instance, doctors would like to know how effective some treatment will be for a patient or why the model suggested a particular medication for a patient exhibiting those symptoms? We acknowledge that the necessity for interpretability is a consequence of an incomplete formalisation of the problem, or more precisely of multiple meanings adhered to a particular concept. For certain problems, it is not enough to get the answer (what), the model also has to provide an explanation of how it came to that conclusion (why), because a correct prediction, only partially solves the original problem. In this article we extend existing categorisation of techniques to aid model interpretability and test this categorisation.
DAGCN: Dual Attention Graph Convolutional Networks
Chen, Fengwen, Pan, Shirui, Jiang, Jing, Huo, Huan, Long, Guodong
Graph convolutional networks (GCNs) have recently become one of the most powerful tools for graph analytics tasks in numerous applications, ranging from social networks and natural language processing to bioinformatics and chemoinformatics, thanks to their ability to capture the complex relationships between concepts. At present, the vast majority of GCNs use a neighborhood aggregation framework to learn a continuous and compact vector, then performing a pooling operation to generalize graph embedding for the classification task. These approaches have two disadvantages in the graph classification task: (1)when only the largest sub-graph structure ($k$-hop neighbor) is used for neighborhood aggregation, a large amount of early-stage information is lost during the graph convolution step; (2) simple average/sum pooling or max pooling utilized, which loses the characteristics of each node and the topology between nodes. In this paper, we propose a novel framework called, dual attention graph convolutional networks (DAGCN) to address these problems. DAGCN automatically learns the importance of neighbors at different hops using a novel attention graph convolution layer, and then employs a second attention component, a self-attention pooling layer, to generalize the graph representation from the various aspects of a matrix graph embedding. The dual attention network is trained in an end-to-end manner for the graph classification task. We compare our model with state-of-the-art graph kernels and other deep learning methods. The experimental results show that our framework not only outperforms other baselines but also achieves a better rate of convergence.
A Strong Baseline for Domain Adaptation and Generalization in Medical Imaging
Yao, Li, Prosky, Jordan, Covington, Ben, Lyman, Kevin
This work provides a strong baseline for the problem of multi-source multi-target domain adaptation and generalization in medical imaging. Using a diverse collection of ten chest X-ray datasets, we empirically demonstrate the benefits of training medical imaging deep learning models on varied patient populations for generalization to out-of-sample domains.
Peak Alignment of GC-MS Data with Deep Learning
GC-MS is regarded as a gold standard in analysis of chemical composition in samples. However, due to the complexity of the instrument, a substance's retention time (RT) may not stay fixed across multiple GC-MS chromatograms. To use GC-MS data for biomarker discovery requires alignment of identical analyte's RT from different samples. Current methods of alignment are all based on a set of formal, mathematical rules, consequently, they are unable to handle the complexity of GC-MS data from human breath. We present a solution to GC-MS alignment using deep learning neural networks, which are more adept at complex, fuzzy data sets. We tested our model on several GC-MS data sets of various complexities and show the model has very good true position rates (up to 99% for easy data sets and up to 92% for very complex data sets). We compared our model with the popular correlation optimized warping (COW) and show our model has much better overall performance. This method can easily be adapted to other similar data such as those from liquid chromatography.
A Gaussian process latent force model for joint input-state estimation in linear structural systems
Nayek, Rajdip, Chakraborty, Souvik, Narasimhan, Sriram
The problem of combined state and input estimation of linear structural systems based on measured responses and a priori knowledge of structural model is considered. A novel methodology using Gaussian process latent force models is proposed to tackle the problem in a stochastic setting. Gaussian process latent force models (GPLFMs) are hybrid models that combine differential equations representing a physical system with data-driven non-parametric Gaussian process models. In this work, the unknown input forces acting on a structure are modelled as Gaussian processes with some chosen covariance functions which are combined with the mechanistic differential equation representing the structure to construct a GPLFM. The GPLFM is then conveniently formulated as an augmented stochastic state-space model with additional states representing the latent force components, and the joint input and state inference of the resulting model is implemented using Kalman filter. The augmented state-space model of GPLFM is shown as a generalization of the class of input-augmented state-space models, is proven observable, and is robust compared to conventional augmented formulations in terms of numerical stability. The hyperparameters governing the covariance functions are estimated using maximum likelihood optimization based on the observed data, thus overcoming the need for manual tuning of the hyperparameters by trial-and-error. To assess the performance of the proposed GPLFM method, several cases of state and input estimation are demonstrated using numerical simulations on a 10-dof shear building and a 76-storey ASCE benchmark office tower. Results obtained indicate the superior performance of the proposed approach over conventional Kalman filter based approaches.
Machine Learning, Big Data, And Smart Buildings: A Comprehensive Survey
Qolomany, Basheer, Al-Fuqaha, Ala, Gupta, Ajay, Benhaddou, Driss, Alwajidi, Safaa, Qadir, Junaid, Fong, Alvis C.
Future buildings will offer new convenience, comfort, and efficiency possibilities to their residents. Changes will occur to the way people live as technology involves into people's lives and information processing is fully integrated into their daily living activities and objects. The future expectation of smart buildings includes making the residents' experience as easy and comfortable as possible. The massive streaming data generated and captured by smart building appliances and devices contains valuable information that needs to be mined to facilitate timely actions and better decision making. Machine learning and big data analytics will undoubtedly play a critical role to enable the delivery of such smart services. In this paper, we survey the area of smart building with a special focus on the role of techniques from machine learning and big data analytics. This survey also reviews the current trends and challenges faced in the development of smart building services.
How the Brain Links Gestures, Perception, and Meaning
Remember the last time someone flipped you the bird? Whether or not that single finger was accompanied by spoken obscenities, you knew exactly what it meant. The conversion from movement into meaning is both seamless and direct, because we are endowed with the capacity to speak without talking and comprehend without hearing. We can direct attention by pointing, enhance narrative by miming, emphasize with rhythmic strokes and convey entire responses with a simple combination of fingers. Original story reprinted with permission from Quanta Magazine, an editorially independent publication of the Simons Foundation whose mission is to enhance public understanding of science by covering research developments and trends in mathematics and the physical and life sciences. The tendency to supplement communication with motion is universal, though the nuances of delivery vary slightly.
How 'The Matrix' Built a Bullet-Proof Legacy
One day in 1992, Lawrence Mattis opened up his mail to find an unsolicited screenplay from two unknown writers. It was a dark, nasty, almost defiantly uncommercial tale of cannibalism and class warfare--the type of story that few execs in Hollywood would want to tell. Yet it was exactly the kind of movie Mattis was looking for. Only a few years earlier, Mattis, in his late twenties, had abandoned a promising legal career to start a talent company, Circle of Confusion, with the aim of discovering new writers to represent. He'd set up shop in New York City, despite being told repeatedly that his best hope for finding talent was to be in Los Angeles. Before that strange script showed up, Mattis was starting to wonder if those naysayers had been right. "I'd only sold a few options that paid about five hundred dollars each," Mattis says. "I was starting to think about going back to law. Then I get this letter from these two kids, saying'Could you please read our script?'" The screenplay, titled Carnivore, was a horror tale set in a soup kitchen, where the bodies of the rich are used to feed the poor. "It was funny, it was visceral, and it made it clear that whoever wrote it really knew movies," Mattis says. Its writers were Lilly and Lana Wachowski, two self-described "schmoes from Chicago" who, in later years, would be referred to by many colleagues and admirers simply as "the Wachowskis." By the time they contacted Mattis, the Wachowskis had been collaborating for years, having spent their childhood creating radio plays, comic books, and their own role-playing game. They'd been raised in a middle-class neighborhood on Chicago's South Side by their mother, a nurse and artist, and their father, a businessman. Growing up, their parents had encouraged them to discover art, especially film.
UK, US and Russia among those opposing killer robot ban
The UK government is among a group of countries that are attempting to thwart plans to formulate and impose a pre-emptive ban on killer robots. Delegates have been meeting at the UN in Geneva all week to discuss potential restrictions under international law to so-called lethal autonomous weapons systems, which use artificial intelligence to help decide when and who to kill. Most states taking part – and particularly those from the global south – support either a total ban or strict legal regulation governing their development and deployment, a position backed by the UN secretary general, António Guterres, who has described machines empowered to kill as "morally repugnant". But the UK is among a group of states – including Australia, Israel, Russia and the US – speaking forcefully against legal regulation. As discussions operate on a consensus basis, their objections are preventing any progress on regulation.