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Deep Haar Scattering Networks in Pattern Recognition: A promising approach

arXiv.org Machine Learning

The aim of this paper is to discuss the use of Haar scattering networks, which is a very simple architecture that naturally supports a large number of stacked layers, yet with very few parameters, in a relatively broad set of pattern recognition problems, including regression and classification tasks. This architecture, basically, consists of stacking convolutional filters, that can be thought as a generalization of Haar wavelets, followed by non-linear operators which aim to extract symmetries and invariances that are later fed in a classification/regression algorithm. We show that good results can be obtained with the proposed method for both kind of tasks. We have outperformed the best available algorithms in 4 out of 18 important data classification problems, and have obtained a more robust performance than ARIMA and ETS time series methods in regression problems for data with strong periodicities.


Distributed dual vigilance fuzzy adaptive resonance theory learns online, retrieves arbitrarily-shaped clusters, and mitigates order dependence

arXiv.org Machine Learning

This paper presents a novel adaptive resonance theory (ART)-based modular architecture for unsupervised learning, namely the distributed dual vigilance fuzzy ART (DDVFA). DDVFA consists of a global ART system whose nodes are local fuzzy ART modules. It is equipped with the distinctive features of distributed higher-order activation and match functions, using dual vigilance parameters responsible for cluster similarity and data quantization. Together, these allow DDVFA to perform unsupervised modularization, create multi-prototype clustering representations, retrieve arbitrarily-shaped clusters, and control its compactness. Another important contribution is the reduction of order-dependence, an issue that affects any agglomerative clustering method. This paper demonstrates two approaches for mitigating order-dependence: preprocessing using visual assessment of cluster tendency (VAT) or postprocessing using a novel Merge ART module. The former is suitable for batch processing, whereas the latter can be used in online learning. Experimental results in the online learning mode carried out on 30 benchmark data sets show that DDVFA cascaded with Merge ART statistically outperformed the best other ART-based systems when samples were randomly presented. Conversely, they were found to be statistically equivalent in the offline mode when samples were pre-processed using VAT. Remarkably, performance comparisons to non-ART-based clustering algorithms show that DDVFA (which learns incrementally) was also statistically equivalent to the non-incremental (offline) methods of DBSCAN, single linkage hierarchical agglomerative clustering (HAC), and k-means, while retaining the appealing properties of ART. Links to the source code and data are provided. Considering the algorithm's simplicity, online learning capability, and performance, it is an ideal choice for many agglomerative clustering applications.


ICPRAI 2018 SI: On dynamic ensemble selection and data preprocessing for multi-class imbalance learning

arXiv.org Machine Learning

Class-imbalance refers to classification problems in which many more instances are available for certain classes than for others. Such imbalanced datasets require special attention because traditional classifiers generally favor the majority class which has a large number of instances. Ensemble of classifiers have been reported to yield promising results. However, the majority of ensemble methods applied to imbalanced learning are static ones. Moreover, they only deal with binary imbalanced problems. Hence, this paper presents an empirical analysis of dynamic selection techniques and data preprocessing methods for dealing with multi-class imbalanced problems. We considered five variations of preprocessing methods and fourteen dynamic selection schemes. Our experiments conducted on 26 multi-class imbalanced problems show that the dynamic ensemble improves the AUC and the G-mean as compared to the static ensemble. Moreover, data preprocessing plays an important role in such cases.


Document classification using a Bi-LSTM to unclog Brazil's supreme court

arXiv.org Machine Learning

The Brazilian court system is currently the most clogged up judiciary system in the world. Thousands of lawsuit cases reach the supreme court every day. These cases need to be analyzed in order to be associated to relevant tags and allocated to the right team. Most of the cases reach the court as raster scanned documents with widely variable levels of quality. One of the first steps for the analysis is to classify these documents. In this paper we present a Bidirectional Long Short-Term Memory network (Bi-LSTM) to classify these pieces of legal document.


Towards Long-Term Memory for Social Robots: Proposing a New Challenge for the RoboCup@Home League

arXiv.org Artificial Intelligence

Long-term memory is essential to feel like a continuous being, and to be able to interact/communicate coherently. Social robots need long-term memories in order to establish long-term relationships with humans and other robots, and do not act just for the moment. In this paper this challenge is highlighted, open questions are identified, the need of addressing this challenge in the RoboCup@Home League with new tests is motivated, and a new test is proposed.


Black Friday 2018: The best Target and Walmart deals you can still get this weekend

USATODAY - Tech Top Stories

WiFi Only 32GB Tablet--$349.99 at Target (Save $250): This sale was originally for $150 off. Assorted Board Games, Video Games, Kids' Books, and Movies--Buy 2 Get 1 Free at Target: This is a great chance to snag gifts for all the kids on your list. Bodum Brazil French Press--$10 at Target (Save $5): This is one of the best French presses we've ever tested down to its lowest price ($5 less than Amazon's selling it for and $10 less than full price). Although the glass does get a bit hot, it's still a great affordable option. BOGO Toys--Buy one get one free at Target: This sale includes major toy brands like Baby Alive, Hot Wheels, Meliisa & Doug, Nerf, and more.


Optimizing positional scoring rules for rank aggregation

arXiv.org Artificial Intelligence

Nowadays, several crowdsourcing projects exploit social choice methods for computing an aggregate ranking of alternatives given individual rankings provided by workers. Motivated by such systems, we consider a setting where each worker is asked to rank a fixed (small) number of alternatives and, then, a positional scoring rule is used to compute the aggregate ranking. Among the apparently infinite such rules, what is the best one to use? To answer this question, we assume that we have partial access to an underlying true ranking. Then, the important optimization problem to be solved is to compute the positional scoring rule whose outcome, when applied to the profile of individual rankings, is as close as possible to the part of the underlying true ranking we know. We study this fundamental problem from a theoretical viewpoint and present positive and negative complexity results and, furthermore, complement our theoretical findings with experiments on real-world and synthetic data.


With Carlos Ghosn in the rearview mirror, Nissan looks forward in fast-changing automobile world

The Japan Times

Carlos Ghosn's ouster as chairman of Nissan Motor Co. signals that the automaker is seeking to reshape itself to better deal with a rapidly changing market environment, breaking from nearly two decades under his charismatic leadership style, according to some analysts. Chasing volume and sharing costs were a large part of Ghosn's business strategy for one of the world's most successful auto partnerships -- the alliance between Nissan, Renault SA and Mitsubishi Motors Corp. -- led by the Brazil-born executive. Nissan officials say they intend to maintain the alliance due to its benefits, even as the company's board on Thursday approved the dismissal of Ghosn as chairman following his arrest for alleged financial misconduct. Ghosn, sent in by Renault in 1999, closed plants, cut thousands of jobs and streamlined its supply chain to pull the automaker back from the brink of bankruptcy. He set lofty numerical targets to propel growth at Nissan, and as a result, the Japanese-French alliance he forged in pursuit of greater economies of scale grew into one of the world's biggest auto groups.


Predicting Diabetes Disease Evolution Using Financial Records and Recurrent Neural Networks

arXiv.org Machine Learning

Managing patients with chronic diseases is a major and growing healthcare challenge in several countries. A chronic condition, such as diabetes, is an illness that lasts a long time and does not go away, and often leads to the patient's health gradually getting worse. While recent works involve raw electronic health record (EHR) from hospitals, this work uses only financial records from health plan providers to predict diabetes disease evolution with a self-attentive recurrent neural network. The use of financial data is due to the possibility of being an interface to international standards, as the records standard encodes medical procedures. The main goal was to assess high risk diabetics, so we predict records related to diabetes acute complications such as amputations and debridements, revascularization and hemodialysis. Our work succeeds to anticipate complications between 60 to 240 days with an area under ROC curve ranging from 0.81 to 0.94. In this paper we describe the first half of a work-in-progress developed within a health plan provider with ROC curve ranging from 0.81 to 0.83. This assessment will give healthcare providers the chance to intervene earlier and head off hospitalizations. We are aiming to deliver personalized predictions and personalized recommendations to individual patients, with the goal of improving outcomes and reducing costs


DarwinML: A Graph-based Evolutionary Algorithm for Automated Machine Learning

arXiv.org Machine Learning

Abstract--As an emerging field, Automated Machine Learning (AutoML) aims to reduce or eliminate manual operations that require expertise in machine learning. In this paper, a graphbased architectureis employed to represent flexible combinations of ML models, which provides a large searching space compared to tree-based and stacking-based architectures. Based on this, an evolutionary algorithm is proposed to search for the best architecture, where the mutation and heredity operators are the key for architecture evolution. With Bayesian hyper-parameter optimization, the proposed approach can automate the workflow of machine learning. On the PMLB dataset, the proposed approach shows the state-of-the-art performance compared with TPOT, Autostacker, and auto-sklearn. Some of the optimized models are with complex structures which are difficult to obtain in manual design. I. INTRODUCTION Various models have been thoroughly investigated by the machine learning (ML) community. In theory, these models are general and applicable to both academia and industry. However, it could be time-consuming to build a solution on a specific ML task, even for a ML expert.