amp Q&A: How to Bolster Cybersecurity in Your Schools By feedproxy.google.com Published On :: Tue, 30 Apr 2019 00:00:00 +0000 Melissa Tebbenkamp, the director of instructional technology for the Raytown Quality Schools near Kansas City, says her district's biggest cybersecurity risk is "ourselves." She outlines what it takes to teach educators how to help protect schools and districts against cyberattacks. Full Article Missouri
amp Introduction to Mindfulness & Manifestation Zine By search.wellcomelibrary.org Published On :: 2017 Full Article
amp L'oeil & la vue : dans l'art, l'histoire et la littérature. By search.wellcomelibrary.org Published On :: Paris, France : Editions Aesculape, [date of publication not identified] Full Article
amp Resilient & Resisting: at Arcola Theatre By search.wellcomelibrary.org Published On :: Full Article
amp Resilient & Resisting: Leather Archive zine By search.wellcomelibrary.org Published On :: Full Article
amp Resilient & resisting: the sex work edition By search.wellcomelibrary.org Published On :: Full Article
amp Resilient & resisting: Hackney Museum our stories By search.wellcomelibrary.org Published On :: Full Article
amp Resilient & resisting: Hackney Museum love & loss By search.wellcomelibrary.org Published On :: Full Article
amp The Umbilical Family / Cate Sawyer & Adriana Avellis. By search.wellcomelibrary.org Published On :: [QLD, Australia] : Hawkeye Publishing, 2018. Full Article
amp Opioids in the hippocampus / editors, Jacqueline F. McGinty, David P. Friedman. By search.wellcomelibrary.org Published On :: Rockville, Maryland : National Institute on Drug Abuse, 1988. Full Article
amp Methamphetamine abuse : epidemiologic issues and implications / editors, Marissa A. Miller, Nicholas J. Kozel. By search.wellcomelibrary.org Published On :: Rockville, Maryland : National Institute on Drug Abuse, 1991. Full Article
amp Management information systems in the drug field / edited by George M. Beschner, Neil H. Sampson, National Institute on Drug Abuse ; and Christopher D'Amanda, Coordinating Office for Drug and Alcohol Abuse, City of Philadelphia. By search.wellcomelibrary.org Published On :: Rockville, Maryland : National Institute on Drug Abuse, 1979. Full Article
amp Food & me : a zine about disordered eating. By search.wellcomelibrary.org Published On :: [London] : [publisher not identified], [2019] Full Article
amp Evaluation of the NIDA drug abuse prevention campaign, 1983-1984 : final report. By search.wellcomelibrary.org Published On :: [United States] : National Technical Information Service, United States Department of Commerce, 1984. Full Article
amp Staley thinks No. 1 South Carolina is national champs By sports.yahoo.com Published On :: Thu, 09 Apr 2020 20:31:23 GMT South Carolina coach Dawn Staley believes her top-ranked Gamecocks are the women's basketball national champions, even without an NCAA Tournament trophy to put in their display case due to the pandemic-shortened season. The NCAA decided against officially crowning champions after its signature tournaments were called off due to the coronavirus pandemic that has sent much of the world into lock down. Staley spoke from her home where she's spent the past month managing her program and ensuring her players don't linger too much on what they missed. Full Article article Sports
amp A fast MCMC algorithm for the uniform sampling of binary matrices with fixed margins By projecteuclid.org Published On :: Thu, 09 Apr 2020 04:00 EDT Guanyang Wang. Source: Electronic Journal of Statistics, Volume 14, Number 1, 1690--1706.Abstract: Uniform sampling of binary matrix with fixed margins is an important and difficult problem in statistics, computer science, ecology and so on. The well-known swap algorithm would be inefficient when the size of the matrix becomes large or when the matrix is too sparse/dense. Here we propose the Rectangle Loop algorithm, a Markov chain Monte Carlo algorithm to sample binary matrices with fixed margins uniformly. Theoretically the Rectangle Loop algorithm is better than the swap algorithm in Peskun’s order. Empirically studies also demonstrates the Rectangle Loop algorithm is remarkablely more efficient than the swap algorithm. Full Article
amp Asymptotic seed bias in respondent-driven sampling By projecteuclid.org Published On :: Wed, 08 Apr 2020 22:01 EDT Yuling Yan, Bret Hanlon, Sebastien Roch, Karl Rohe. Source: Electronic Journal of Statistics, Volume 14, Number 1, 1577--1610.Abstract: Respondent-driven sampling (RDS) collects a sample of individuals in a networked population by incentivizing the sampled individuals to refer their contacts into the sample. This iterative process is initialized from some seed node(s). Sometimes, this selection creates a large amount of seed bias. Other times, the seed bias is small. This paper gains a deeper understanding of this bias by characterizing its effect on the limiting distribution of various RDS estimators. Using classical tools and results from multi-type branching processes [12], we show that the seed bias is negligible for the Generalized Least Squares (GLS) estimator and non-negligible for both the inverse probability weighted and Volz-Heckathorn (VH) estimators. In particular, we show that (i) above a critical threshold, VH converge to a non-trivial mixture distribution, where the mixture component depends on the seed node, and the mixture distribution is possibly multi-modal. Moreover, (ii) GLS converges to a Gaussian distribution independent of the seed node, under a certain condition on the Markov process. Numerical experiments with both simulated data and empirical social networks suggest that these results appear to hold beyond the Markov conditions of the theorems. Full Article
amp $k$-means clustering of extremes By projecteuclid.org Published On :: Mon, 02 Mar 2020 22:02 EST Anja Janßen, Phyllis Wan. Source: Electronic Journal of Statistics, Volume 14, Number 1, 1211--1233.Abstract: The $k$-means clustering algorithm and its variant, the spherical $k$-means clustering, are among the most important and popular methods in unsupervised learning and pattern detection. In this paper, we explore how the spherical $k$-means algorithm can be applied in the analysis of only the extremal observations from a data set. By making use of multivariate extreme value analysis we show how it can be adopted to find “prototypes” of extremal dependence and derive a consistency result for our suggested estimator. In the special case of max-linear models we show furthermore that our procedure provides an alternative way of statistical inference for this class of models. Finally, we provide data examples which show that our method is able to find relevant patterns in extremal observations and allows us to classify extremal events. Full Article
amp On a Metropolis–Hastings importance sampling estimator By projecteuclid.org Published On :: Mon, 10 Feb 2020 04:01 EST Daniel Rudolf, Björn Sprungk. Source: Electronic Journal of Statistics, Volume 14, Number 1, 857--889.Abstract: A classical approach for approximating expectations of functions w.r.t. partially known distributions is to compute the average of function values along a trajectory of a Metropolis–Hastings (MH) Markov chain. A key part in the MH algorithm is a suitable acceptance/rejection of a proposed state, which ensures the correct stationary distribution of the resulting Markov chain. However, the rejection of proposals causes highly correlated samples. In particular, when a state is rejected it is not taken any further into account. In contrast to that we consider a MH importance sampling estimator which explicitly incorporates all proposed states generated by the MH algorithm. The estimator satisfies a strong law of large numbers as well as a central limit theorem, and, in addition to that, we provide an explicit mean squared error bound. Remarkably, the asymptotic variance of the MH importance sampling estimator does not involve any correlation term in contrast to its classical counterpart. Moreover, although the analyzed estimator uses the same amount of information as the classical MH estimator, it can outperform the latter in scenarios of moderate dimensions as indicated by numerical experiments. Full Article
amp Neyman-Pearson classification: parametrics and sample size requirement By Published On :: 2020 The Neyman-Pearson (NP) paradigm in binary classification seeks classifiers that achieve a minimal type II error while enforcing the prioritized type I error controlled under some user-specified level $alpha$. This paradigm serves naturally in applications such as severe disease diagnosis and spam detection, where people have clear priorities among the two error types. Recently, Tong, Feng, and Li (2018) proposed a nonparametric umbrella algorithm that adapts all scoring-type classification methods (e.g., logistic regression, support vector machines, random forest) to respect the given type I error (i.e., conditional probability of classifying a class $0$ observation as class $1$ under the 0-1 coding) upper bound $alpha$ with high probability, without specific distributional assumptions on the features and the responses. Universal the umbrella algorithm is, it demands an explicit minimum sample size requirement on class $0$, which is often the more scarce class, such as in rare disease diagnosis applications. In this work, we employ the parametric linear discriminant analysis (LDA) model and propose a new parametric thresholding algorithm, which does not need the minimum sample size requirements on class $0$ observations and thus is suitable for small sample applications such as rare disease diagnosis. Leveraging both the existing nonparametric and the newly proposed parametric thresholding rules, we propose four LDA-based NP classifiers, for both low- and high-dimensional settings. On the theoretical front, we prove NP oracle inequalities for one proposed classifier, where the rate for excess type II error benefits from the explicit parametric model assumption. Furthermore, as NP classifiers involve a sample splitting step of class $0$ observations, we construct a new adaptive sample splitting scheme that can be applied universally to NP classifiers, and this adaptive strategy reduces the type II error of these classifiers. The proposed NP classifiers are implemented in the R package nproc. Full Article
amp On the consistency of graph-based Bayesian semi-supervised learning and the scalability of sampling algorithms By Published On :: 2020 This paper considers a Bayesian approach to graph-based semi-supervised learning. We show that if the graph parameters are suitably scaled, the graph-posteriors converge to a continuum limit as the size of the unlabeled data set grows. This consistency result has profound algorithmic implications: we prove that when consistency holds, carefully designed Markov chain Monte Carlo algorithms have a uniform spectral gap, independent of the number of unlabeled inputs. Numerical experiments illustrate and complement the theory. Full Article
amp Provably robust estimation of modulo 1 samples of a smooth function with applications to phase unwrapping By Published On :: 2020 Consider an unknown smooth function $f: [0,1]^d ightarrow mathbb{R}$, and assume we are given $n$ noisy mod 1 samples of $f$, i.e., $y_i = (f(x_i) + eta_i) mod 1$, for $x_i in [0,1]^d$, where $eta_i$ denotes the noise. Given the samples $(x_i,y_i)_{i=1}^{n}$, our goal is to recover smooth, robust estimates of the clean samples $f(x_i) mod 1$. We formulate a natural approach for solving this problem, which works with angular embeddings of the noisy mod 1 samples over the unit circle, inspired by the angular synchronization framework. This amounts to solving a smoothness regularized least-squares problem -- a quadratically constrained quadratic program (QCQP) -- where the variables are constrained to lie on the unit circle. Our proposed approach is based on solving its relaxation, which is a trust-region sub-problem and hence solvable efficiently. We provide theoretical guarantees demonstrating its robustness to noise for adversarial, as well as random Gaussian and Bernoulli noise models. To the best of our knowledge, these are the first such theoretical results for this problem. We demonstrate the robustness and efficiency of our proposed approach via extensive numerical simulations on synthetic data, along with a simple least-squares based solution for the unwrapping stage, that recovers the original samples of $f$ (up to a global shift). It is shown to perform well at high levels of noise, when taking as input the denoised modulo $1$ samples. Finally, we also consider two other approaches for denoising the modulo 1 samples that leverage tools from Riemannian optimization on manifolds, including a Burer-Monteiro approach for a semidefinite programming relaxation of our formulation. For the two-dimensional version of the problem, which has applications in synthetic aperture radar interferometry (InSAR), we are able to solve instances of real-world data with a million sample points in under 10 seconds, on a personal laptop. Full Article
amp Greedy Attack and Gumbel Attack: Generating Adversarial Examples for Discrete Data By Published On :: 2020 We present a probabilistic framework for studying adversarial attacks on discrete data. Based on this framework, we derive a perturbation-based method, Greedy Attack, and a scalable learning-based method, Gumbel Attack, that illustrate various tradeoffs in the design of attacks. We demonstrate the effectiveness of these methods using both quantitative metrics and human evaluation on various state-of-the-art models for text classification, including a word-based CNN, a character-based CNN and an LSTM. As an example of our results, we show that the accuracy of character-based convolutional networks drops to the level of random selection by modifying only five characters through Greedy Attack. Full Article
amp Ancestral Gumbel-Top-k Sampling for Sampling Without Replacement By Published On :: 2020 We develop ancestral Gumbel-Top-$k$ sampling: a generic and efficient method for sampling without replacement from discrete-valued Bayesian networks, which includes multivariate discrete distributions, Markov chains and sequence models. The method uses an extension of the Gumbel-Max trick to sample without replacement by finding the top $k$ of perturbed log-probabilities among all possible configurations of a Bayesian network. Despite the exponentially large domain, the algorithm has a complexity linear in the number of variables and sample size $k$. Our algorithm allows to set the number of parallel processors $m$, to trade off the number of iterations versus the total cost (iterations times $m$) of running the algorithm. For $m = 1$ the algorithm has minimum total cost, whereas for $m = k$ the number of iterations is minimized, and the resulting algorithm is known as Stochastic Beam Search. We provide extensions of the algorithm and discuss a number of related algorithms. We analyze the properties of ancestral Gumbel-Top-$k$ sampling and compare against alternatives on randomly generated Bayesian networks with different levels of connectivity. In the context of (deep) sequence models, we show its use as a method to generate diverse but high-quality translations and statistical estimates of translation quality and entropy. Full Article
amp Q&A with Tara June Winch By feedproxy.google.com Published On :: Mon, 27 Apr 2020 01:40:36 +0000 Tara June Winch's profound novel The Yield has won three NSW Premier's Literary Awards prizes this year, inclu Full Article
amp Q&A with Adam Ferguson By feedproxy.google.com Published On :: Tue, 05 May 2020 05:43:41 +0000 Each year the Library hosts the popular World Press Photo exhibition, bringing together award-winning photographs from t Full Article
amp Youth & Community Initiatives Funding available By www.eastgwillimbury.ca Published On :: Thu, 20 Feb 2020 18:27:25 GMT Full Article
amp Health & Active Living Challenge By www.eastgwillimbury.ca Published On :: Wed, 15 Apr 2020 17:19:39 GMT Full Article
amp $W^{1,p}$-Solutions of the transport equation by stochastic perturbation By projecteuclid.org Published On :: Mon, 03 Feb 2020 04:00 EST David A. C. Mollinedo. Source: Brazilian Journal of Probability and Statistics, Volume 34, Number 1, 188--201.Abstract: We consider the stochastic transport equation with a possibly unbounded Hölder continuous vector field. Well-posedness is proved, namely, we show existence, uniqueness and strong stability of $W^{1,p}$-weak solutions. Full Article
amp The limiting distribution of the Gibbs sampler for the intrinsic conditional autoregressive model By projecteuclid.org Published On :: Mon, 26 Aug 2019 04:00 EDT Marco A. R. Ferreira. Source: Brazilian Journal of Probability and Statistics, Volume 33, Number 4, 734--744.Abstract: We study the limiting behavior of the one-at-a-time Gibbs sampler for the intrinsic conditional autoregressive model with centering on the fly. The intrinsic conditional autoregressive model is widely used as a prior for random effects in hierarchical models for spatial modeling. This model is defined by full conditional distributions that imply an improper joint “density” with a multivariate Gaussian kernel and a singular precision matrix. To guarantee propriety of the posterior distribution, usually at the end of each iteration of the Gibbs sampler the random effects are centered to sum to zero in what is widely known as centering on the fly. While this works well in practice, this informal computational way to recenter the random effects obscures their implied prior distribution and prevents the development of formal Bayesian procedures. Here we show that the implied prior distribution, that is, the limiting distribution of the one-at-a-time Gibbs sampler for the intrinsic conditional autoregressive model with centering on the fly is a singular Gaussian distribution with a covariance matrix that is the Moore–Penrose inverse of the precision matrix. This result has important implications for the development of formal Bayesian procedures such as reference priors and Bayes-factor-based model selection for spatial models. Full Article
amp Keeping the balance—Bridge sampling for marginal likelihood estimation in finite mixture, mixture of experts and Markov mixture models By projecteuclid.org Published On :: Mon, 26 Aug 2019 04:00 EDT Sylvia Frühwirth-Schnatter. Source: Brazilian Journal of Probability and Statistics, Volume 33, Number 4, 706--733.Abstract: Finite mixture models and their extensions to Markov mixture and mixture of experts models are very popular in analysing data of various kind. A challenge for these models is choosing the number of components based on marginal likelihoods. The present paper suggests two innovative, generic bridge sampling estimators of the marginal likelihood that are based on constructing balanced importance densities from the conditional densities arising during Gibbs sampling. The full permutation bridge sampling estimator is derived from considering all possible permutations of the mixture labels for a subset of these densities. For the double random permutation bridge sampling estimator, two levels of random permutations are applied, first to permute the labels of the MCMC draws and second to randomly permute the labels of the conditional densities arising during Gibbs sampling. Various applications show very good performance of these estimators in comparison to importance and to reciprocal importance sampling estimators derived from the same importance densities. Full Article
amp Estimation of parameters in the $operatorname{DDRCINAR}(p)$ model By projecteuclid.org Published On :: Mon, 10 Jun 2019 04:04 EDT Xiufang Liu, Dehui Wang. Source: Brazilian Journal of Probability and Statistics, Volume 33, Number 3, 638--673.Abstract: This paper discusses a $p$th-order dependence-driven random coefficient integer-valued autoregressive time series model ($operatorname{DDRCINAR}(p)$). Stationarity and ergodicity properties are proved. Conditional least squares, weighted least squares and maximum quasi-likelihood are used to estimate the model parameters. Asymptotic properties of the estimators are presented. The performances of these estimators are investigated and compared via simulations. In certain regions of the parameter space, simulative analysis shows that maximum quasi-likelihood estimators perform better than the estimators of conditional least squares and weighted least squares in terms of the proportion of within-$Omega$ estimates. At last, the model is applied to two real data sets. Full Article
amp A rank-based Cramér–von-Mises-type test for two samples By projecteuclid.org Published On :: Mon, 10 Jun 2019 04:04 EDT Jamye Curry, Xin Dang, Hailin Sang. Source: Brazilian Journal of Probability and Statistics, Volume 33, Number 3, 425--454.Abstract: We study a rank based univariate two-sample distribution-free test. The test statistic is the difference between the average of between-group rank distances and the average of within-group rank distances. This test statistic is closely related to the two-sample Cramér–von Mises criterion. They are different empirical versions of a same quantity for testing the equality of two population distributions. Although they may be different for finite samples, they share the same expected value, variance and asymptotic properties. The advantage of the new rank based test over the classical one is its ease to generalize to the multivariate case. Rather than using the empirical process approach, we provide a different easier proof, bringing in a different perspective and insight. In particular, we apply the Hájek projection and orthogonal decomposition technique in deriving the asymptotics of the proposed rank based statistic. A numerical study compares power performance of the rank formulation test with other commonly-used nonparametric tests and recommendations on those tests are provided. Lastly, we propose a multivariate extension of the test based on the spatial rank. Full Article
amp Can $p$-values be meaningfully interpreted without random sampling? By projecteuclid.org Published On :: Thu, 26 Mar 2020 22:02 EDT Norbert Hirschauer, Sven Grüner, Oliver Mußhoff, Claudia Becker, Antje Jantsch. Source: Statistics Surveys, Volume 14, 71--91.Abstract: Besides the inferential errors that abound in the interpretation of $p$-values, the probabilistic pre-conditions (i.e. random sampling or equivalent) for using them at all are not often met by observational studies in the social sciences. This paper systematizes different sampling designs and discusses the restrictive requirements of data collection that are the indispensable prerequisite for using $p$-values. Full Article
amp Estimating the size of a hidden finite set: Large-sample behavior of estimators By projecteuclid.org Published On :: Fri, 03 Jan 2020 22:02 EST Si Cheng, Daniel J. Eck, Forrest W. Crawford. Source: Statistics Surveys, Volume 14, 1--31.Abstract: A finite set is “hidden” if its elements are not directly enumerable or if its size cannot be ascertained via a deterministic query. In public health, epidemiology, demography, ecology and intelligence analysis, researchers have developed a wide variety of indirect statistical approaches, under different models for sampling and observation, for estimating the size of a hidden set. Some methods make use of random sampling with known or estimable sampling probabilities, and others make structural assumptions about relationships (e.g. ordering or network information) between the elements that comprise the hidden set. In this review, we describe models and methods for learning about the size of a hidden finite set, with special attention to asymptotic properties of estimators. We study the properties of these methods under two asymptotic regimes, “infill” in which the number of fixed-size samples increases, but the population size remains constant, and “outfill” in which the sample size and population size grow together. Statistical properties under these two regimes can be dramatically different. Full Article
amp Pitfalls of significance testing and $p$-value variability: An econometrics perspective By projecteuclid.org Published On :: Wed, 03 Oct 2018 22:00 EDT Norbert Hirschauer, Sven Grüner, Oliver Mußhoff, Claudia Becker. Source: Statistics Surveys, Volume 12, 136--172.Abstract: Data on how many scientific findings are reproducible are generally bleak and a wealth of papers have warned against misuses of the $p$-value and resulting false findings in recent years. This paper discusses the question of what we can(not) learn from the $p$-value, which is still widely considered as the gold standard of statistical validity. We aim to provide a non-technical and easily accessible resource for statistical practitioners who wish to spot and avoid misinterpretations and misuses of statistical significance tests. For this purpose, we first classify and describe the most widely discussed (“classical”) pitfalls of significance testing, and review published work on these misuses with a focus on regression-based “confirmatory” study. This includes a description of the single-study bias and a simulation-based illustration of how proper meta-analysis compares to misleading significance counts (“vote counting”). Going beyond the classical pitfalls, we also use simulation to provide intuition that relying on the statistical estimate “$p$-value” as a measure of evidence without considering its sample-to-sample variability falls short of the mark even within an otherwise appropriate interpretation. We conclude with a discussion of the exigencies of informed approaches to statistical inference and corresponding institutional reforms. Full Article
amp A survey of bootstrap methods in finite population sampling By projecteuclid.org Published On :: Tue, 15 Mar 2016 09:17 EDT Zeinab Mashreghi, David Haziza, Christian Léger. Source: Statistics Surveys, Volume 10, 1--52.Abstract: We review bootstrap methods in the context of survey data where the effect of the sampling design on the variability of estimators has to be taken into account. We present the methods in a unified way by classifying them in three classes: pseudo-population, direct, and survey weights methods. We cover variance estimation and the construction of confidence intervals for stratified simple random sampling as well as some unequal probability sampling designs. We also address the problem of variance estimation in presence of imputation to compensate for item non-response. Full Article
amp Holtermann and the A&A Photographic Company By feedproxy.google.com Published On :: Thu, 10 Sep 2015 02:50:04 +0000 We recently received a comment about authorship of the Holtermann Collection. Although it may seem a purely historica Full Article
amp Arctic Amplification of Anthropogenic Forcing: A Vector Autoregressive Analysis. (arXiv:2005.02535v1 [econ.EM] CROSS LISTED) By arxiv.org Published On :: Arctic sea ice extent (SIE) in September 2019 ranked second-to-lowest in history and is trending downward. The understanding of how internal variability amplifies the effects of external $ ext{CO}_2$ forcing is still limited. We propose the VARCTIC, which is a Vector Autoregression (VAR) designed to capture and extrapolate Arctic feedback loops. VARs are dynamic simultaneous systems of equations, routinely estimated to predict and understand the interactions of multiple macroeconomic time series. Hence, the VARCTIC is a parsimonious compromise between fullblown climate models and purely statistical approaches that usually offer little explanation of the underlying mechanism. Our "business as usual" completely unconditional forecast has SIE hitting 0 in September by the 2060s. Impulse response functions reveal that anthropogenic $ ext{CO}_2$ emission shocks have a permanent effect on SIE - a property shared by no other shock. Further, we find Albedo- and Thickness-based feedbacks to be the main amplification channels through which $ ext{CO}_2$ anomalies impact SIE in the short/medium run. Conditional forecast analyses reveal that the future path of SIE crucially depends on the evolution of $ ext{CO}_2$ emissions, with outcomes ranging from recovering SIE to it reaching 0 in the 2050s. Finally, Albedo and Thickness feedbacks are shown to play an important role in accelerating the speed at which predicted SIE is heading towards 0. Full Article
amp Generating Thermal Image Data Samples using 3D Facial Modelling Techniques and Deep Learning Methodologies. (arXiv:2005.01923v2 [cs.CV] UPDATED) By arxiv.org Published On :: Methods for generating synthetic data have become of increasing importance to build large datasets required for Convolution Neural Networks (CNN) based deep learning techniques for a wide range of computer vision applications. In this work, we extend existing methodologies to show how 2D thermal facial data can be mapped to provide 3D facial models. For the proposed research work we have used tufts datasets for generating 3D varying face poses by using a single frontal face pose. The system works by refining the existing image quality by performing fusion based image preprocessing operations. The refined outputs have better contrast adjustments, decreased noise level and higher exposedness of the dark regions. It makes the facial landmarks and temperature patterns on the human face more discernible and visible when compared to original raw data. Different image quality metrics are used to compare the refined version of images with original images. In the next phase of the proposed study, the refined version of images is used to create 3D facial geometry structures by using Convolution Neural Networks (CNN). The generated outputs are then imported in blender software to finally extract the 3D thermal facial outputs of both males and females. The same technique is also used on our thermal face data acquired using prototype thermal camera (developed under Heliaus EU project) in an indoor lab environment which is then used for generating synthetic 3D face data along with varying yaw face angles and lastly facial depth map is generated. Full Article
amp Sampling random graph homomorphisms and applications to network data analysis. (arXiv:1910.09483v2 [math.PR] UPDATED) By arxiv.org Published On :: A graph homomorphism is a map between two graphs that preserves adjacency relations. We consider the problem of sampling a random graph homomorphism from a graph $F$ into a large network $mathcal{G}$. We propose two complementary MCMC algorithms for sampling a random graph homomorphisms and establish bounds on their mixing times and concentration of their time averages. Based on our sampling algorithms, we propose a novel framework for network data analysis that circumvents some of the drawbacks in methods based on independent and neigborhood sampling. Various time averages of the MCMC trajectory give us various computable observables, including well-known ones such as homomorphism density and average clustering coefficient and their generalizations. Furthermore, we show that these network observables are stable with respect to a suitably renormalized cut distance between networks. We provide various examples and simulations demonstrating our framework through synthetic networks. We also apply our framework for network clustering and classification problems using the Facebook100 dataset and Word Adjacency Networks of a set of classic novels. Full Article
amp Convergence rates for optimised adaptive importance samplers. (arXiv:1903.12044v4 [stat.CO] UPDATED) By arxiv.org Published On :: Adaptive importance samplers are adaptive Monte Carlo algorithms to estimate expectations with respect to some target distribution which extit{adapt} themselves to obtain better estimators over a sequence of iterations. Although it is straightforward to show that they have the same $mathcal{O}(1/sqrt{N})$ convergence rate as standard importance samplers, where $N$ is the number of Monte Carlo samples, the behaviour of adaptive importance samplers over the number of iterations has been left relatively unexplored. In this work, we investigate an adaptation strategy based on convex optimisation which leads to a class of adaptive importance samplers termed extit{optimised adaptive importance samplers} (OAIS). These samplers rely on the iterative minimisation of the $chi^2$-divergence between an exponential-family proposal and the target. The analysed algorithms are closely related to the class of adaptive importance samplers which minimise the variance of the weight function. We first prove non-asymptotic error bounds for the mean squared errors (MSEs) of these algorithms, which explicitly depend on the number of iterations and the number of samples together. The non-asymptotic bounds derived in this paper imply that when the target belongs to the exponential family, the $L_2$ errors of the optimised samplers converge to the optimal rate of $mathcal{O}(1/sqrt{N})$ and the rate of convergence in the number of iterations are explicitly provided. When the target does not belong to the exponential family, the rate of convergence is the same but the asymptotic $L_2$ error increases by a factor $sqrt{ ho^star} > 1$, where $ ho^star - 1$ is the minimum $chi^2$-divergence between the target and an exponential-family proposal. Full Article
amp Predictive Modeling of ICU Healthcare-Associated Infections from Imbalanced Data. Using Ensembles and a Clustering-Based Undersampling Approach. (arXiv:2005.03582v1 [cs.LG]) By arxiv.org Published On :: Early detection of patients vulnerable to infections acquired in the hospital environment is a challenge in current health systems given the impact that such infections have on patient mortality and healthcare costs. This work is focused on both the identification of risk factors and the prediction of healthcare-associated infections in intensive-care units by means of machine-learning methods. The aim is to support decision making addressed at reducing the incidence rate of infections. In this field, it is necessary to deal with the problem of building reliable classifiers from imbalanced datasets. We propose a clustering-based undersampling strategy to be used in combination with ensemble classifiers. A comparative study with data from 4616 patients was conducted in order to validate our proposal. We applied several single and ensemble classifiers both to the original dataset and to data preprocessed by means of different resampling methods. The results were analyzed by means of classic and recent metrics specifically designed for imbalanced data classification. They revealed that the proposal is more efficient in comparison with other approaches. Full Article
amp Multi-Label Sampling based on Local Label Imbalance. (arXiv:2005.03240v1 [cs.LG]) By arxiv.org Published On :: Class imbalance is an inherent characteristic of multi-label data that hinders most multi-label learning methods. One efficient and flexible strategy to deal with this problem is to employ sampling techniques before training a multi-label learning model. Although existing multi-label sampling approaches alleviate the global imbalance of multi-label datasets, it is actually the imbalance level within the local neighbourhood of minority class examples that plays a key role in performance degradation. To address this issue, we propose a novel measure to assess the local label imbalance of multi-label datasets, as well as two multi-label sampling approaches based on the local label imbalance, namely MLSOL and MLUL. By considering all informative labels, MLSOL creates more diverse and better labeled synthetic instances for difficult examples, while MLUL eliminates instances that are harmful to their local region. Experimental results on 13 multi-label datasets demonstrate the effectiveness of the proposed measure and sampling approaches for a variety of evaluation metrics, particularly in the case of an ensemble of classifiers trained on repeated samples of the original data. Full Article
amp Orchid biology : recent trends & challenges By dal.novanet.ca Published On :: Fri, 1 May 2020 19:44:43 -0300 Callnumber: OnlineISBN: 9789813294561 (electronic bk.) Full Article
amp Diabetes & obesity in women : adolescence, pregnancy, and menopause By dal.novanet.ca Published On :: Fri, 1 May 2020 19:44:43 -0300 Author: Diabetes in women.Callnumber: OnlineISBN: 9781496390547 (paperback) Full Article
amp Gun Rights: California Gun Owners & Ammo Dealers Fire Back Against... By www.prweb.com Published On :: Ammunition Depot comments on Judge Roger T. Benitez ruling that Californians may again purchase ammo without a background check and order ammo online.(PRWeb April 24, 2020)Read the full story at https://www.prweb.com/releases/gun_rights_california_gun_owners_ammo_dealers_fire_back_against_proposition_63/prweb17075447.htm Full Article
amp Consistent selection of the number of change-points via sample-splitting By projecteuclid.org Published On :: Mon, 17 Feb 2020 04:02 EST Changliang Zou, Guanghui Wang, Runze Li. Source: The Annals of Statistics, Volume 48, Number 1, 413--439.Abstract: In multiple change-point analysis, one of the major challenges is to estimate the number of change-points. Most existing approaches attempt to minimize a Schwarz information criterion which balances a term quantifying model fit with a penalization term accounting for model complexity that increases with the number of change-points and limits overfitting. However, different penalization terms are required to adapt to different contexts of multiple change-point problems and the optimal penalization magnitude usually varies from the model and error distribution. We propose a data-driven selection criterion that is applicable to most kinds of popular change-point detection methods, including binary segmentation and optimal partitioning algorithms. The key idea is to select the number of change-points that minimizes the squared prediction error, which measures the fit of a specified model for a new sample. We develop a cross-validation estimation scheme based on an order-preserved sample-splitting strategy, and establish its asymptotic selection consistency under some mild conditions. Effectiveness of the proposed selection criterion is demonstrated on a variety of numerical experiments and real-data examples. Full Article
amp New $G$-formula for the sequential causal effect and blip effect of treatment in sequential causal inference By projecteuclid.org Published On :: Mon, 17 Feb 2020 04:02 EST Xiaoqin Wang, Li Yin. Source: The Annals of Statistics, Volume 48, Number 1, 138--160.Abstract: In sequential causal inference, two types of causal effects are of practical interest, namely, the causal effect of the treatment regime (called the sequential causal effect) and the blip effect of treatment on the potential outcome after the last treatment. The well-known $G$-formula expresses these causal effects in terms of the standard parameters. In this article, we obtain a new $G$-formula that expresses these causal effects in terms of the point observable effects of treatments similar to treatment in the framework of single-point causal inference. Based on the new $G$-formula, we estimate these causal effects by maximum likelihood via point observable effects with methods extended from single-point causal inference. We are able to increase precision of the estimation without introducing biases by an unsaturated model imposing constraints on the point observable effects. We are also able to reduce the number of point observable effects in the estimation by treatment assignment conditions. Full Article