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Bayes Factors for Partially Observed Stochastic Epidemic Models

Muteb Alharthi, Theodore Kypraios, Philip D. O’Neill.

Source: Bayesian Analysis, Volume 14, Number 3, 927--956.

Abstract:
We consider the problem of model choice for stochastic epidemic models given partial observation of a disease outbreak through time. Our main focus is on the use of Bayes factors. Although Bayes factors have appeared in the epidemic modelling literature before, they can be hard to compute and little attention has been given to fundamental questions concerning their utility. In this paper we derive analytic expressions for Bayes factors given complete observation through time, which suggest practical guidelines for model choice problems. We adapt the power posterior method for computing Bayes factors so as to account for missing data and apply this approach to partially observed epidemics. For comparison, we also explore the use of a deviance information criterion for missing data scenarios. The methods are illustrated via examples involving both simulated and real data.




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Model Criticism in Latent Space

Sohan Seth, Iain Murray, Christopher K. I. Williams.

Source: Bayesian Analysis, Volume 14, Number 3, 703--725.

Abstract:
Model criticism is usually carried out by assessing if replicated data generated under the fitted model looks similar to the observed data, see e.g. Gelman, Carlin, Stern, and Rubin (2004, p. 165). This paper presents a method for latent variable models by pulling back the data into the space of latent variables, and carrying out model criticism in that space. Making use of a model's structure enables a more direct assessment of the assumptions made in the prior and likelihood. We demonstrate the method with examples of model criticism in latent space applied to factor analysis, linear dynamical systems and Gaussian processes.




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Alleviating Spatial Confounding for Areal Data Problems by Displacing the Geographical Centroids

Marcos Oliveira Prates, Renato Martins Assunção, Erica Castilho Rodrigues.

Source: Bayesian Analysis, Volume 14, Number 2, 623--647.

Abstract:
Spatial confounding between the spatial random effects and fixed effects covariates has been recently discovered and showed that it may bring misleading interpretation to the model results. Techniques to alleviate this problem are based on decomposing the spatial random effect and fitting a restricted spatial regression. In this paper, we propose a different approach: a transformation of the geographic space to ensure that the unobserved spatial random effect added to the regression is orthogonal to the fixed effects covariates. Our approach, named SPOCK, has the additional benefit of providing a fast and simple computational method to estimate the parameters. Also, it does not constrain the distribution class assumed for the spatial error term. A simulation study and real data analyses are presented to better understand the advantages of the new method in comparison with the existing ones.




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Efficient Acquisition Rules for Model-Based Approximate Bayesian Computation

Marko Järvenpää, Michael U. Gutmann, Arijus Pleska, Aki Vehtari, Pekka Marttinen.

Source: Bayesian Analysis, Volume 14, Number 2, 595--622.

Abstract:
Approximate Bayesian computation (ABC) is a method for Bayesian inference when the likelihood is unavailable but simulating from the model is possible. However, many ABC algorithms require a large number of simulations, which can be costly. To reduce the computational cost, Bayesian optimisation (BO) and surrogate models such as Gaussian processes have been proposed. Bayesian optimisation enables one to intelligently decide where to evaluate the model next but common BO strategies are not designed for the goal of estimating the posterior distribution. Our paper addresses this gap in the literature. We propose to compute the uncertainty in the ABC posterior density, which is due to a lack of simulations to estimate this quantity accurately, and define a loss function that measures this uncertainty. We then propose to select the next evaluation location to minimise the expected loss. Experiments show that the proposed method often produces the most accurate approximations as compared to common BO strategies.




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Fast Model-Fitting of Bayesian Variable Selection Regression Using the Iterative Complex Factorization Algorithm

Quan Zhou, Yongtao Guan.

Source: Bayesian Analysis, Volume 14, Number 2, 573--594.

Abstract:
Bayesian variable selection regression (BVSR) is able to jointly analyze genome-wide genetic datasets, but the slow computation via Markov chain Monte Carlo (MCMC) hampered its wide-spread usage. Here we present a novel iterative method to solve a special class of linear systems, which can increase the speed of the BVSR model-fitting tenfold. The iterative method hinges on the complex factorization of the sum of two matrices and the solution path resides in the complex domain (instead of the real domain). Compared to the Gauss-Seidel method, the complex factorization converges almost instantaneously and its error is several magnitude smaller than that of the Gauss-Seidel method. More importantly, the error is always within the pre-specified precision while the Gauss-Seidel method is not. For large problems with thousands of covariates, the complex factorization is 10–100 times faster than either the Gauss-Seidel method or the direct method via the Cholesky decomposition. In BVSR, one needs to repetitively solve large penalized regression systems whose design matrices only change slightly between adjacent MCMC steps. This slight change in design matrix enables the adaptation of the iterative complex factorization method. The computational innovation will facilitate the wide-spread use of BVSR in reanalyzing genome-wide association datasets.




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Bayes Factor Testing of Multiple Intraclass Correlations

Joris Mulder, Jean-Paul Fox.

Source: Bayesian Analysis, Volume 14, Number 2, 521--552.

Abstract:
The intraclass correlation plays a central role in modeling hierarchically structured data, such as educational data, panel data, or group-randomized trial data. It represents relevant information concerning the between-group and within-group variation. Methods for Bayesian hypothesis tests concerning the intraclass correlation are proposed to improve decision making in hierarchical data analysis and to assess the grouping effect across different group categories. Estimation and testing methods for the intraclass correlation coefficient are proposed under a marginal modeling framework where the random effects are integrated out. A class of stretched beta priors is proposed on the intraclass correlations, which is equivalent to shifted $F$ priors for the between groups variances. Through a parameter expansion it is shown that this prior is conditionally conjugate under the marginal model yielding efficient posterior computation. A special improper case results in accurate coverage rates of the credible intervals even for minimal sample size and when the true intraclass correlation equals zero. Bayes factor tests are proposed for testing multiple precise and order hypotheses on intraclass correlations. These tests can be used when prior information about the intraclass correlations is available or absent. For the noninformative case, a generalized fractional Bayes approach is developed. The method enables testing the presence and strength of grouped data structures without introducing random effects. The methodology is applied to a large-scale survey study on international mathematics achievement at fourth grade to test the heterogeneity in the clustering of students in schools across countries and assessment cycles.




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A Bayesian Approach to Statistical Shape Analysis via the Projected Normal Distribution

Luis Gutiérrez, Eduardo Gutiérrez-Peña, Ramsés H. Mena.

Source: Bayesian Analysis, Volume 14, Number 2, 427--447.

Abstract:
This work presents a Bayesian predictive approach to statistical shape analysis. A modeling strategy that starts with a Gaussian distribution on the configuration space, and then removes the effects of location, rotation and scale, is studied. This boils down to an application of the projected normal distribution to model the configurations in the shape space, which together with certain identifiability constraints, facilitates parameter interpretation. Having better control over the parameters allows us to generalize the model to a regression setting where the effect of predictors on shapes can be considered. The methodology is illustrated and tested using both simulated scenarios and a real data set concerning eight anatomical landmarks on a sagittal plane of the corpus callosum in patients with autism and in a group of controls.




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Model-Based Approach to the Joint Analysis of Single-Cell Data on Chromatin Accessibility and Gene Expression

Zhixiang Lin, Mahdi Zamanighomi, Timothy Daley, Shining Ma, Wing Hung Wong.

Source: Statistical Science, Volume 35, Number 1, 2--13.

Abstract:
Unsupervised methods, including clustering methods, are essential to the analysis of single-cell genomic data. Model-based clustering methods are under-explored in the area of single-cell genomics, and have the advantage of quantifying the uncertainty of the clustering result. Here we develop a model-based approach for the integrative analysis of single-cell chromatin accessibility and gene expression data. We show that combining these two types of data, we can achieve a better separation of the underlying cell types. An efficient Markov chain Monte Carlo algorithm is also developed.




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Gaussianization Machines for Non-Gaussian Function Estimation Models

T. Tony Cai.

Source: Statistical Science, Volume 34, Number 4, 635--656.

Abstract:
A wide range of nonparametric function estimation models have been studied individually in the literature. Among them the homoscedastic nonparametric Gaussian regression is arguably the best known and understood. Inspired by the asymptotic equivalence theory, Brown, Cai and Zhou ( Ann. Statist. 36 (2008) 2055–2084; Ann. Statist. 38 (2010) 2005–2046) and Brown et al. ( Probab. Theory Related Fields 146 (2010) 401–433) developed a unified approach to turn a collection of non-Gaussian function estimation models into a standard Gaussian regression and any good Gaussian nonparametric regression method can then be used. These Gaussianization Machines have two key components, binning and transformation. When combined with BlockJS, a wavelet thresholding procedure for Gaussian regression, the procedures are computationally efficient with strong theoretical guarantees. Technical analysis given in Brown, Cai and Zhou ( Ann. Statist. 36 (2008) 2055–2084; Ann. Statist. 38 (2010) 2005–2046) and Brown et al. ( Probab. Theory Related Fields 146 (2010) 401–433) shows that the estimators attain the optimal rate of convergence adaptively over a large set of Besov spaces and across a collection of non-Gaussian function estimation models, including robust nonparametric regression, density estimation, and nonparametric regression in exponential families. The estimators are also spatially adaptive. The Gaussianization Machines significantly extend the flexibility and scope of the theories and methodologies originally developed for the conventional nonparametric Gaussian regression. This article aims to provide a concise account of the Gaussianization Machines developed in Brown, Cai and Zhou ( Ann. Statist. 36 (2008) 2055–2084; Ann. Statist. 38 (2010) 2005–2046), Brown et al. ( Probab. Theory Related Fields 146 (2010) 401–433).




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The Geometry of Continuous Latent Space Models for Network Data

Anna L. Smith, Dena M. Asta, Catherine A. Calder.

Source: Statistical Science, Volume 34, Number 3, 428--453.

Abstract:
We review the class of continuous latent space (statistical) models for network data, paying particular attention to the role of the geometry of the latent space. In these models, the presence/absence of network dyadic ties are assumed to be conditionally independent given the dyads’ unobserved positions in a latent space. In this way, these models provide a probabilistic framework for embedding network nodes in a continuous space equipped with a geometry that facilitates the description of dependence between random dyadic ties. Specifically, these models naturally capture homophilous tendencies and triadic clustering, among other common properties of observed networks. In addition to reviewing the literature on continuous latent space models from a geometric perspective, we highlight the important role the geometry of the latent space plays on properties of networks arising from these models via intuition and simulation. Finally, we discuss results from spectral graph theory that allow us to explore the role of the geometry of the latent space, independent of network size. We conclude with conjectures about how these results might be used to infer the appropriate latent space geometry from observed networks.




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A Kernel Regression Procedure in the 3D Shape Space with an Application to Online Sales of Children’s Wear

Gregorio Quintana-Ortí, Amelia Simó.

Source: Statistical Science, Volume 34, Number 2, 236--252.

Abstract:
This paper is focused on kernel regression when the response variable is the shape of a 3D object represented by a configuration matrix of landmarks. Regression methods on this shape space are not trivial because this space has a complex finite-dimensional Riemannian manifold structure (non-Euclidean). Papers about it are scarce in the literature, the majority of them are restricted to the case of a single explanatory variable, and many of them are based on the approximated tangent space. In this paper, there are several methodological innovations. The first one is the adaptation of the general method for kernel regression analysis in manifold-valued data to the three-dimensional case of Kendall’s shape space. The second one is its generalization to the multivariate case and the addressing of the curse-of-dimensionality problem. Finally, we propose bootstrap confidence intervals for prediction. A simulation study is carried out to check the goodness of the procedure, and a comparison with a current approach is performed. Then, it is applied to a 3D database obtained from an anthropometric survey of the Spanish child population with a potential application to online sales of children’s wear.




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Rejoinder: Bayes, Oracle Bayes, and Empirical Bayes

Bradley Efron.

Source: Statistical Science, Volume 34, Number 2, 234--235.




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Comment: Bayes, Oracle Bayes and Empirical Bayes

Aad van der Vaart.

Source: Statistical Science, Volume 34, Number 2, 214--218.




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Comment: Bayes, Oracle Bayes, and Empirical Bayes

Nan Laird.

Source: Statistical Science, Volume 34, Number 2, 206--208.




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Comment: Bayes, Oracle Bayes, and Empirical Bayes

Thomas A. Louis.

Source: Statistical Science, Volume 34, Number 2, 202--205.




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Bayes, Oracle Bayes and Empirical Bayes

Bradley Efron.

Source: Statistical Science, Volume 34, Number 2, 177--201.

Abstract:
This article concerns the Bayes and frequentist aspects of empirical Bayes inference. Some of the ideas explored go back to Robbins in the 1950s, while others are current. Several examples are discussed, real and artificial, illustrating the two faces of empirical Bayes methodology: “oracle Bayes” shows empirical Bayes in its most frequentist mode, while “finite Bayes inference” is a fundamentally Bayesian application. In either case, modern theory and computation allow us to present a sharp finite-sample picture of what is at stake in an empirical Bayes analysis.




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Comment: Contributions of Model Features to BART Causal Inference Performance Using ACIC 2016 Competition Data

Nicole Bohme Carnegie.

Source: Statistical Science, Volume 34, Number 1, 90--93.

Abstract:
With a thorough exposition of the methods and results of the 2016 Atlantic Causal Inference Competition, Dorie et al. have set a new standard for reproducibility and comparability of evaluations of causal inference methods. In particular, the open-source R package aciccomp2016, which permits reproduction of all datasets used in the competition, will be an invaluable resource for evaluation of future methodological developments. Building upon results from Dorie et al., we examine whether a set of potential modifications to Bayesian Additive Regression Trees (BART)—multiple chains in model fitting, using the propensity score as a covariate, targeted maximum likelihood estimation (TMLE), and computing symmetric confidence intervals—have a stronger impact on bias, RMSE, and confidence interval coverage in combination than they do alone. We find that bias in the estimate of SATT is minimal, regardless of the BART formulation. For purposes of CI coverage, however, all proposed modifications are beneficial—alone and in combination—but use of TMLE is least beneficial for coverage and results in considerably wider confidence intervals.




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Tapadh leibh airson nach do smoc sibh / design : Biman Mullick.

London (33 Stillness Rd, SE23 1NG) : Cleanair, Campaign for a Smoke-free Environment, [198-?]




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Muchas gracias por no fumar / Biman Mullick.

London : Cleanair, [1988?]




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Gracias por no fumar / deseño : Biman Mullick.

[London] : Cleanair, Campaña para un Medio Ambiente Libre de Humo, [198-?]




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Muchas gracias por no fumar / Biman Mullick.

[London] : Cleanair, [1989?]




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Tapadh leibh airson nach do smoc sibh / design: Biman Mullick.

London (33 Stillness Road London SE23 1NG) : Cleanair Campaign for a Smoke-free Environment, [198-?]




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Each year in Britain 9,300 babies are killed by their smoking mums. / Biman Mullick.

[London?], [6th June 1990]




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How can the smoker and the nonsmoker be equally free in the same place? George Bernard Shaw / Biman Mullick.

[London?], [199-?]




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Karachi Plague Committee in 1897. Album of photographs.

1897.




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The 2019 Victoria’s Secret Fashion Show Is Canceled After Facing Backlash for Lack of Body Diversity

The reaction on social media has been fierce.




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Taylor Swift, Hailey Bieber, and Tons of Other Celebs’ Favorite Leggings Are on Sale Ahead of Black Friday

Here’s where you can snag their Alo Yoga Moto leggings for less.




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Gabrielle Union's Mesmerizing Tie Dye Activewear Set Is On Sale for Black Friday

The rainbow sports bra and leggings set from Splits59 is a must-have for anyone craving a pop of color in their workout wardrobe.




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These Nordstrom Cyber Monday Deals Are Giving Black Friday a Run for Its Money

This is not a drill: You can get up to 50% off at Nordstrom right now.




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Macy’s Insane Cyber Monday Sale Ends in a Few Hours—Here Are the Best Deals

You've got exactly four hours left to take advantage of these heavily discounted prices.




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These Clark Booties Are Actually Comfortable Enough to Wear All Day—and They’re on Sale

You can save 50% right now. 




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Forget Black Booties, Amal Clooney and J.Lo Are Wearing This Weather-Resistant Boot Trend Instead

And it’s on sale at Nordstrom.




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This is the Only Jacket I’ll Be Living in This Winter

Canada Goose has long been a leader in the outdoor gear space.




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Optimization of a GCaMP Calcium Indicator for Neural Activity Imaging

Jasper Akerboom
Oct 3, 2012; 32:13819-13840
Cellular




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Metacognitive Mechanisms Underlying Lucid Dreaming

Elisa Filevich
Jan 21, 2015; 35:1082-1088
BehavioralSystemsCognitive




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Brain-Derived Neurotrophic Factor Protection of Cortical Neurons from Serum Withdrawal-Induced Apoptosis Is Inhibited by cAMP

Steven Poser
Jun 1, 2003; 23:4420-4427
Cellular




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Physical Exercise Prevents Stress-Induced Activation of Granule Neurons and Enhances Local Inhibitory Mechanisms in the Dentate Gyrus

Timothy J. Schoenfeld
May 1, 2013; 33:7770-7777
BehavioralSystemsCognitive




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Genomic Analysis of Reactive Astrogliosis

Jennifer L. Zamanian
May 2, 2012; 32:6391-6410
Neurobiology of Disease




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Microglia Actively Remodel Adult Hippocampal Neurogenesis through the Phagocytosis Secretome

Irune Diaz-Aparicio
Feb 12, 2020; 40:1453-1482
Development Plasticity Repair




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The Pain of Sleep Loss: A Brain Characterization in Humans

Adam J. Krause
Mar 20, 2019; 39:2291-2300
BehavioralSystemsCognitive




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{Delta}9-Tetrahydrocannabinol and Cannabinol Activate Capsaicin-Sensitive Sensory Nerves via a CB1 and CB2 Cannabinoid Receptor-Independent Mechanism

Peter M. Zygmunt
Jun 1, 2002; 22:4720-4727
Behavioral




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Nurture versus Nature: Long-Term Impact of Forced Right-Handedness on Structure of Pericentral Cortex and Basal Ganglia

Stefan Klöppel
Mar 3, 2010; 30:3271-3275
BRIEF COMMUNICATION




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The Representation of Semantic Information Across Human Cerebral Cortex During Listening Versus Reading Is Invariant to Stimulus Modality

Fatma Deniz
Sep 25, 2019; 39:7722-7736
BehavioralSystemsCognitive




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Astrocytes Modulate Baroreflex Sensitivity at the Level of the Nucleus of the Solitary Tract

Svetlana Mastitskaya
Apr 8, 2020; 40:3052-3062
Systems/Circuits




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Neurobiological Mechanisms of the Placebo Effect

Fabrizio Benedetti
Nov 9, 2005; 25:10390-10402
Symposia and Mini-Symposia




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Interactions of Top-Down and Bottom-Up Mechanisms in Human Visual Cortex

Stephanie McMains
Jan 12, 2011; 31:587-597
BehavioralSystemsCognitive




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Endothelial Adora2a Activation Promotes Blood-Brain Barrier Breakdown and Cognitive Impairment in Mice with Diet-Induced Insulin Resistance

Masaki Yamamoto
May 22, 2019; 39:4179-4192
Neurobiology of Disease




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Sleep Loss Promotes Astrocytic Phagocytosis and Microglial Activation in Mouse Cerebral Cortex

Michele Bellesi
May 24, 2017; 37:5263-5273
Cellular




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Increased Neural Activity in Mesostriatal Regions after Prefrontal Transcranial Direct Current Stimulation and L-DOPA Administration

Benjamin Meyer
Jul 3, 2019; 39:5326-5335
Systems/Circuits




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The Fusiform Face Area: A Module in Human Extrastriate Cortex Specialized for Face Perception

Nancy Kanwisher
Jun 1, 1997; 17:4302-4311
Articles