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Machine Learning Tips and Tricks for Power Line Communications

arXiv.org Machine Learning

A great deal of attention has been recently given to Machine Learning (ML) techniques in many different application fields. This paper provides a vision of what ML can do in Power Line Communications (PLC). We firstly and briefly describe classical formulations of ML, and distinguish deterministic problems from statistical problems with relevance to communications. We then discuss ML applications in PLC for each layer, namely, for characterization and modeling, for physical layer algorithms, for media access control and networking algorithms. Finally, other applications of PLC that can benefit from the usage of ML, as grid diagnostics, are analyzed. Illustrative numerical examples are reported to serve the purpose of validating the ideas and motivate future research endeavors in this stimulating signal/data processing field.


GAN Augmented Text Anomaly Detection with Sequences of Deep Statistics

arXiv.org Machine Learning

Anomaly detection is the process of finding data points that deviate from a baseline. In a real-life setting, anomalies are usually unknown or extremely rare. Moreover, the detection must be accomplished in a timely manner or the risk of corrupting the system might grow exponentially. In this work, we propose a two level framework for detecting anomalies in sequences of discrete elements. First, we assess whether we can obtain enough information from the statistics collected from the discriminator's layers to discriminate between out of distribution and in distribution samples. We then build an unsupervised anomaly detection module based on these statistics. As to augment the data and keep track of classes of known data, we lean toward a semi-supervised adversarial learning applied to discrete elements.


Bayesian leave-one-out cross-validation for large data

arXiv.org Machine Learning

Model inference, such as model comparison, model checking, and model selection, is an important part of model development. Leave-one-out cross-validation (LOO) is a general approach for assessing the generalizability of a model, but unfortunately, LOO does not scale well to large datasets. We propose a combination of using approximate inference techniques and probability-proportional-to-size-sampling (PPS) for fast LOO model evaluation for large datasets. We provide both theoretical and empirical results showing good properties for large data.


Diagnosis of Celiac Disease and Environmental Enteropathy on Biopsy Images Using Color Balancing on Convolutional Neural Networks

arXiv.org Machine Learning

Celiac Disease (CD) and Environmental Enteropathy (EE) are common causes of malnutrition and adversely impact normal childhood development. CD is an autoimmune disorder that is prevalent worldwide and is caused by an increased sensitivity to gluten. Gluten exposure destructs the small intestinal epithelial barrier, resulting in nutrient mal-absorption and childhood under-nutrition. EE also results in barrier dysfunction but is thought to be caused by an increased vulnerability to infections. EE has been implicated as the predominant cause of under-nutrition, oral vaccine failure, and impaired cognitive development in low-and-middle-income countries. Both conditions require a tissue biopsy for diagnosis, and a major challenge of interpreting clinical biopsy images to differentiate between these gastrointestinal diseases is striking histopathologic overlap between them. In the current study, we propose a convolutional neural network (CNN) to classify duodenal biopsy images from subjects with CD, EE, and healthy controls. We evaluated the performance of our proposed model using a large cohort containing 1000 biopsy images. Our evaluations show that the proposed model achieves an area under ROC of 0.99, 1.00, and 0.97 for CD, EE, and healthy controls, respectively. These results demonstrate the discriminative power of the proposed model in duodenal biopsies classification.


Tracking and Improving Information in the Service of Fairness

arXiv.org Machine Learning

As algorithmic prediction systems have become widespread, fears that these systems may inadvertently discriminate against members of underrepresented populations have grown. With the goal of understanding fundamental principles that underpin the growing number of approaches to mitigating algorithmic discrimination, we investigate the role of information in fair prediction. A common strategy for decision-making uses a predictor to assign individuals a risk score; then, individuals are selected or rejected on the basis of this score. In this work, we formalize a framework for measuring the information content of predictors. Central to this framework is the notion of a refinement; intuitively, a refinement of a predictor $z$ increases the overall informativeness of the predictions without losing the information already contained in $z$. We show that increasing information content through refinements improves the downstream selection rules across a wide range of fairness measures (e.g. true positive rates, false positive rates, selection rates). In turn, refinements provide a simple but effective tool for reducing disparity in treatment and impact without sacrificing the utility of the predictions. Our results suggest that in many applications, the perceived "cost of fairness" results from an information disparity across populations, and thus, may be avoided with improved information.


Tracking as A Whole: Multi-Target Tracking by Modeling Group Behavior with Sequential Detection

arXiv.org Artificial Intelligence

Video-based vehicle detection and tracking is one of the most important components for Intelligent Transportation Systems (ITS). When it comes to road junctions, the problem becomes even more difficult due to the occlusions and complex interactions among vehicles. In order to get a precise detection and tracking result, in this work we propose a novel tracking-by-detection framework. In the detection stage, we present a sequential detection model to deal with serious occlusions. In the tracking stage, we model group behavior to treat complex interactions with overlaps and ambiguities. The main contributions of this paper are twofold: 1) Shape prior is exploited in the sequential detection model to tackle occlusions in crowded scene. 2) Traffic force is defined in the traffic scene to model group behavior, and it can assist to handle complex interactions among vehicles. We evaluate the proposed approach on real surveillance videos at road junctions and the performance has demonstrated the effectiveness of our method.


Achieving the Bayes Error Rate in Synchronization and Block Models by SDP, Robustly

arXiv.org Machine Learning

We study the statistical performance of semidefinite programming (SDP) relaxations for clustering under random graph models. Under the $\mathbb{Z}_{2}$ Synchronization model, Censored Block Model and Stochastic Block Model, we show that SDP achieves an error rate of the form \[ \exp\Big[-\big(1-o(1)\big)\bar{n} I^* \Big]. \] Here $\bar{n}$ is an appropriate multiple of the number of nodes and $I^*$ is an information-theoretic measure of the signal-to-noise ratio. We provide matching lower bounds on the Bayes error for each model and therefore demonstrate that the SDP approach is Bayes optimal. As a corollary, our results imply that SDP achieves the optimal exact recovery threshold under each model. Furthermore, we show that SDP is robust: the above bound remains valid under semirandom versions of the models in which the observed graph is modified by a monotone adversary. Our proof is based on a novel primal-dual analysis of SDP under a unified framework for all three models, and the analysis shows that SDP tightly approximates a joint majority voting procedure.


FBI's use of facial recognition software is under fire AGAIN

Daily Mail - Science & tech

The FBI has failed to appease concerns about the use of its facial recognition technology in criminal investigations. Multiple issues were raised three years ago after a congressional watchdog urged the bureau to improve its practices in order to meet privacy and accuracy standards. The FBI - and other US law enforcement agencies - have been using the Next Generation Identification-Interstate Photo System since 2015. It uses facial recognition software to link potential suspects to crimes from a vast database of 30 million pictures, including mugshots. The report slamming the FBI for its failure to moderate the software comes as the bureau increases its use of the technology.


Distributed generation of privacy preserving data with user customization

arXiv.org Machine Learning

Distributed devices such as mobile phones can produce and store large amounts of data that can enhance machine learning models; however, this data may contain private information specific to the data owner that prevents the release of the data. We wish to reduce the correlation between user-specific private information and data while maintaining the useful information. Rather than learning a large model to achieve privatization from end to end, we introduce a decoupling of the creation of a latent representation and the privatization of data that allows user-specific privatization to occur in a distributed setting with limited computation and minimal disturbance on the utility of the data. We leverage a Variational Autoencoder (VAE) to create a compact latent representation of the data; however, the VAE remains fixed for all devices and all possible private labels. We then train a small generative filter to perturb the latent representation based on individual preferences regarding the private and utility information. The small filter is trained by utilizing a GAN-type robust optimization that can take place on a distributed device. We conduct experiments on three popular datasets: MNIST, UCI-Adult, and CelebA, and give a thorough evaluation including visualizing the geometry of the latent embeddings and estimating the empirical mutual information to show the effectiveness of our approach. The success of machine learning algorithms relies on not only technical methodologies, but also the availability of large datasets such as images (Krizhevsky et al., 2012; Oshri et al., 2018); however, data can often contain sensitive information, such as race or age, that may hinder the owner's ability to release the data to exploit its utility. We are interested in exploring methods of providing privatized data such that sensitive information cannot be easily inferred from the adversarial perspective, while preserving the utility of the dataset. In particular, we consider a setting where many participants are independently gathering data that will be collected by a third party.


Can Machine Learning Model with Static Features be Fooled: an Adversarial Machine Learning Approach

arXiv.org Artificial Intelligence

Applied Intelligence manuscript No. (will be inserted by the editor) Abstract The widespread adoption of smartphones dramaticallygenerated by our attacks models when used to harden increases the risk of attacks and the spread the developed anti-malware system improves the detection of mobile malware, especially on the Android platform. Machine learning based solutions have been already Keywords Adversarial machine learning · malware used as a tool to supersede signature based anti-malware detection · poison attacks · adversarial example · systems. However, malware authors leverage attributes jacobian algorithm. Hence, to evaluate the vulnerability of machine 1 Introduction learning algorithms in malware detection, we propose five different attack scenarios to perturb malicious applications Nowadays using the Android application is very popular (apps). Every Android application inappropriately fits discriminant function on has a Jar-like APK format and is an archive file which the set of data points, eventually yielding a higher misclassification contains Android manifest and Classes.dex Further, to distinguish the adversarial manifest file holds information about the application examples from benign samples, we propose two defense structure and each part responsible for certain actions. To validate our For instance, the requested permissions must be accepted attacks and solutions, we test our model on three different by the users for successful installation of applications. We also test our methods The manifest file contains a list of hardware using various classifier algorithms and compare them components and permissions required by each application. Promising results show that generated the manifest file that are useful for running applications. Additionally, evasive variants is saved as the classes.dex In a nutshell, the by presenting some adversary-aware approaches?generated malware sample is statistically identical to a Do we require retraining of the current ML model to designbenign sample. To do so, adversaries adopt adversarial adversary-aware learning algorithms? How to properlymachine learning algorithms (AML) to design an example test and validate the countermeasure solutions inset called poison data which is used to fool machine a real-world network? The goal of this paper is to shedlearning models.