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Sequential Monte Carlo Samplers with Independent Markov Chain Monte Carlo Proposals

L. F. South, A. N. Pettitt, C. C. Drovandi.

Source: Bayesian Analysis, Volume 14, Number 3, 773--796.

Abstract:
Sequential Monte Carlo (SMC) methods for sampling from the posterior of static Bayesian models are flexible, parallelisable and capable of handling complex targets. However, it is common practice to adopt a Markov chain Monte Carlo (MCMC) kernel with a multivariate normal random walk (RW) proposal in the move step, which can be both inefficient and detrimental for exploring challenging posterior distributions. We develop new SMC methods with independent proposals which allow recycling of all candidates generated in the SMC process and are embarrassingly parallelisable. A novel evidence estimator that is easily computed from the output of our independent SMC is proposed. Our independent proposals are constructed via flexible copula-type models calibrated with the population of SMC particles. We demonstrate through several examples that more precise estimates of posterior expectations and the marginal likelihood can be obtained using fewer likelihood evaluations than the more standard RW approach.




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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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Control of Type I Error Rates in Bayesian Sequential Designs

Haolun Shi, Guosheng Yin.

Source: Bayesian Analysis, Volume 14, Number 2, 399--425.

Abstract:
Bayesian approaches to phase II clinical trial designs are usually based on the posterior distribution of the parameter of interest and calibration of certain threshold for decision making. If the posterior probability is computed and assessed in a sequential manner, the design may involve the problem of multiplicity, which, however, is often a neglected aspect in Bayesian trial designs. To effectively maintain the overall type I error rate, we propose solutions to the problem of multiplicity for Bayesian sequential designs and, in particular, the determination of the cutoff boundaries for the posterior probabilities. We present both theoretical and numerical methods for finding the optimal posterior probability boundaries with $alpha$ -spending functions that mimic those of the frequentist group sequential designs. The theoretical approach is based on the asymptotic properties of the posterior probability, which establishes a connection between the Bayesian trial design and the frequentist group sequential method. The numerical approach uses a sandwich-type searching algorithm, which immensely reduces the computational burden. We apply least-square fitting to find the $alpha$ -spending function closest to the target. We discuss the application of our method to single-arm and double-arm cases with binary and normal endpoints, respectively, and provide a real trial example for each case.




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Data Denoising and Post-Denoising Corrections in Single Cell RNA Sequencing

Divyansh Agarwal, Jingshu Wang, Nancy R. Zhang.

Source: Statistical Science, Volume 35, Number 1, 112--128.

Abstract:
Single cell sequencing technologies are transforming biomedical research. However, due to the inherent nature of the data, single cell RNA sequencing analysis poses new computational and statistical challenges. We begin with a survey of a selection of topics in this field, with a gentle introduction to the biology and a more detailed exploration of the technical noise. We consider in detail the problem of single cell data denoising, sometimes referred to as “imputation” in the relevant literature. We discuss why this is not a typical statistical imputation problem, and review current approaches to this problem. We then explore why the use of denoised values in downstream analyses invites novel statistical insights, and how denoising uncertainty should be accounted for to yield valid statistical inference. The utilization of denoised or imputed matrices in statistical inference is not unique to single cell genomics, and arises in many other fields. We describe the challenges in this type of analysis, discuss some preliminary solutions, and highlight unresolved issues.




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Statistical Molecule Counting in Super-Resolution Fluorescence Microscopy: Towards Quantitative Nanoscopy

Thomas Staudt, Timo Aspelmeier, Oskar Laitenberger, Claudia Geisler, Alexander Egner, Axel Munk.

Source: Statistical Science, Volume 35, Number 1, 92--111.

Abstract:
Super-resolution microscopy is rapidly gaining importance as an analytical tool in the life sciences. A compelling feature is the ability to label biological units of interest with fluorescent markers in (living) cells and to observe them with considerably higher resolution than conventional microscopy permits. The images obtained this way, however, lack an absolute intensity scale in terms of numbers of fluorophores observed. In this article, we discuss state of the art methods to count such fluorophores and statistical challenges that come along with it. In particular, we suggest a modeling scheme for time series generated by single-marker-switching (SMS) microscopy that makes it possible to quantify the number of markers in a statistically meaningful manner from the raw data. To this end, we model the entire process of photon generation in the fluorophore, their passage through the microscope, detection and photoelectron amplification in the camera, and extraction of time series from the microscopic images. At the heart of these modeling steps is a careful description of the fluorophore dynamics by a novel hidden Markov model that operates on two timescales (HTMM). Besides the fluorophore number, information about the kinetic transition rates of the fluorophore’s internal states is also inferred during estimation. We comment on computational issues that arise when applying our model to simulated or measured fluorescence traces and illustrate our methodology on simulated data.




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Quantum Science and Quantum Technology

Yazhen Wang, Xinyu Song.

Source: Statistical Science, Volume 35, Number 1, 51--74.

Abstract:
Quantum science and quantum technology are of great current interest in multiple frontiers of many scientific fields ranging from computer science to physics and chemistry, and from engineering to mathematics and statistics. Their developments will likely lead to a new wave of scientific revolutions and technological innovations in a wide range of scientific studies and applications. This paper provides a brief review on quantum communication, quantum information, quantum computation, quantum simulation, and quantum metrology. We present essential quantum properties, illustrate relevant concepts of quantum science and quantum technology, and discuss their scientific developments. We point out the need for statistical analysis in their developments, as well as their potential applications to and impacts on statistics and data science.




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Comment: “Models as Approximations I: Consequences Illustrated with Linear Regression” by A. Buja, R. Berk, L. Brown, E. George, E. Pitkin, L. Zhan and K. Zhang

Roderick J. Little.

Source: Statistical Science, Volume 34, Number 4, 580--583.




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Models as Approximations I: Consequences Illustrated with Linear Regression

Andreas Buja, Lawrence Brown, Richard Berk, Edward George, Emil Pitkin, Mikhail Traskin, Kai Zhang, Linda Zhao.

Source: Statistical Science, Volume 34, Number 4, 523--544.

Abstract:
In the early 1980s, Halbert White inaugurated a “model-robust” form of statistical inference based on the “sandwich estimator” of standard error. This estimator is known to be “heteroskedasticity-consistent,” but it is less well known to be “nonlinearity-consistent” as well. Nonlinearity, however, raises fundamental issues because in its presence regressors are not ancillary, hence cannot be treated as fixed. The consequences are deep: (1) population slopes need to be reinterpreted as statistical functionals obtained from OLS fits to largely arbitrary joint ${x extrm{-}y}$ distributions; (2) the meaning of slope parameters needs to be rethought; (3) the regressor distribution affects the slope parameters; (4) randomness of the regressors becomes a source of sampling variability in slope estimates of order $1/sqrt{N}$; (5) inference needs to be based on model-robust standard errors, including sandwich estimators or the ${x extrm{-}y}$ bootstrap. In theory, model-robust and model-trusting standard errors can deviate by arbitrary magnitudes either way. In practice, significant deviations between them can be detected with a diagnostic test.




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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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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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Editor’s Pick: Gifts for Your Tech-Obsessed Friend

A guide to the tech gadgets even your hard-to-shop-for friends and family members will love.




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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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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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Katie Holmes’s Affordable Sneakers Are the Star of Her Latest Outfit

Meghan Markle is also a fan of the comfy shoes.




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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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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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Of Course Katie Holmes Found This Year’s Coziest Winter Boot

Keep your feet happy this winter.




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Advances in Enteric Neurobiology: The "Brain" in the Gut in Health and Disease

Subhash Kulkarni
Oct 31, 2018; 38:9346-9354
Symposium and Mini-Symposium




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An RNA-Sequencing Transcriptome and Splicing Database of Glia, Neurons, and Vascular Cells of the Cerebral Cortex

Ye Zhang
Sep 3, 2014; 34:11929-11947
Cellular




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Correction: Sequerra, Goyal et al., "NMDA Receptor Signaling Is Important for Neural Tube Formation and for Preventing Antiepileptic Drug-Induced Neural Tube Defects"




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Head-direction cells recorded from the postsubiculum in freely moving rats. I. Description and quantitative analysis

JS Taube
Feb 1, 1990; 10:420-435
Articles




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Neural Mechanisms of Visual Working Memory in Prefrontal Cortex of the Macaque

Earl K. Miller
Aug 15, 1996; 16:5154-5167
Articles




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Effects of Attention on Orientation-Tuning Functions of Single Neurons in Macaque Cortical Area V4

Carrie J. McAdams
Jan 1, 1999; 19:431-441
Articles




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Quantitative Ultrastructural Analysis of Hippocampal Excitatory Synapses

Thomas Schikorski
Aug 1, 1997; 17:5858-5867
Articles




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Pax6, Tbr2, and Tbr1 Are Expressed Sequentially by Radial Glia, Intermediate Progenitor Cells, and Postmitotic Neurons in Developing Neocortex

Chris Englund
Jan 5, 2005; 25:247-251
BRIEF COMMUNICATION




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Linearity and Normalization in Simple Cells of the Macaque Primary Visual Cortex

Matteo Carandini
Nov 1, 1997; 17:8621-8644
Articles




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High-Level Neuronal Expression of A{beta}1-42 in Wild-Type Human Amyloid Protein Precursor Transgenic Mice: Synaptotoxicity without Plaque Formation

Lennart Mucke
Jun 1, 2000; 20:4050-4058
Cellular




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An RNA-Sequencing Transcriptome and Splicing Database of Glia, Neurons, and Vascular Cells of the Cerebral Cortex

Ye Zhang
Sep 3, 2014; 34:11929-11947
Cellular




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Aquatics Instructor




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Guardare oltre il qui e ora

Italian translation of the speech delivered by Mr Jaime Caruana, General Manager of the BIS, on the occasion of the Bank's Annual General Meeting, Basel, 25 June 2017.




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Implications des évolutions de la technologie financière pour les banques et les autorités de contrôle bancaire

French translation of the Basel Committee is publishing "Sound Practices: implications of fintech developments for banks and bank supervisors", February 2018.




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Questions fréquemment posées sur les exigences de fonds propres en regard du risque de marché

French translation of "Frequently asked questions on market risk capital requirements" by the Basel Committee, March 2018.




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La confiance est le chaînon manquant des cryptomonnaies actuelles, selon la BRI

French translation of the Press Release on the pre-release of two special chapters of the Annual Economic Report of the BIS, 17 June 2018. Trust is the missing link in today's cryptocurrencies - Cryptocurrencies' model of generating trust limits their potential to replace conventional money, the Bank for International Settlements (BIS) writes in its Annual Economic Report (AER), a new title launched this year.




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Rapport économique annuel 2018

French translation of the Annual Economic Report 2018 of the BIS, June 2018 - Les responsables des politiques publiques peuvent prolonger la phase de croissance actuelle en engageant des réformes structurelles, en restaurant les marges de manœuvre monétaires et budgétaires pour faire face aux menaces futures et en encourageant une mise en œuvre rapide des réformes réglementaires, indique la Banque des Règlements Internationaux (BRI) dans son Rapport économique annuel.




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Soutenir la dynamique de croissance

French translation of speech delivered by Mr Agustín Carstens, General Manager of the BIS, on the occasion of the Bank's Annual General Meeting, Basel, 24 June 2018. Mesdames et Messieurs, j'ai le plaisir de vous présenter aujourd'hui la première édition du Rapport économique annuel de la BRI. Les trois premiers chapitres analysent les évolutions, perspectives et risques de l'économie mondiale, en s'attachant plus particulièrement à la politique monétaire et aux réformes de la réglementation financière, aux marchés et aux acteurs de l'intermédiation. Nous consacrons deux chapitres spéciaux à des enjeux actuels : une analyse des dispositifs macroprudentiels d'une part, une étude relative aux cryptomonnaies d'autre part....




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Le Communiqué de Bâle finalise les principes relatifs aux tests de résistance, passe en revue les moyens pour mettre fin aux comportements d'arbitrage réglementaire, s'accorde sur la liste annuelle des G-SIB et discute du ratio

French translation of press release - the Basel Committee on Banking Supervision is finalising stress-testing principles, reviews ways to stop regulatory arbitrage behaviour, agrees on annual G-SIB list, discusses leverage ratio, crypto-assets, market risk framework and implementation, 20 September 2018.




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Les banques centrales et la dette : des risques émergents pour l efficacité de la politique monétaire en Afrique

French translation of BIS Papers No 99 - Central banks and debt: emerging risks to the effectiveness of monetary policy in Africa?, October 2018.




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Les Big Tech dans la finance : opportunités et risques

French version of BIS Press Release - Big tech in finance: opportunities and risks, 23 June 2019




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Rapport économique annuel de la BRI : Il est temps d'allumer tous les moteurs

French translation of the BIS press release on the presentation of the Annual Economic Report 2019, 30 June 2019. La politique monétaire ne peut plus être le principal moteur de la croissance économique, et d'autres leviers de politique publique doivent être actionnés pour faire en sorte que l'économie mondiale connaisse une dynamique durable ...




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Preguntas frecuentes sobre requerimientos de capital por riesgo de mercado

Spanish translation of "Frequently asked questions on market risk capital requirements" by the Basel Committee, March 2018.




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Requisitos de divulgación para el Tercer Pilar - Macro actualizado

Spanish translation of "Pillar 3 disclosure requirements - updated framework", December 2018




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poetry reading i just quit my job today




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ASÍ QUE LO LOGRASTE QUIÉN IBA A DECIRLO. FELICIDADES Y ¡BIENVENIDO! S V




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Fry saying "Oh Snap!" - :fry:




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a frog saying "get out" - :frogon:




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Don't be a drama queen - :darksouls:




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End-of-day stock quote: WTFC: 38.64

Price ($):38.64
Change ($):2.39
Change (%):6.59
Volume:517,584
High ($):38.92
Low ($):37.14






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Wintrust Financial Corporation Reports Record Full-Year 2019 Net Income of $355.7 million and Fourth Quarter 2019 Net Income of $86.0 million, up 8% from the Fourth Quarter 2018

To view more press releases, please visit http://www.snl.com/irweblinkx/news.aspx?iid=1024452.