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Related papers: Copula-based robust optimal block designs

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In recent biomedical scientific problems, it is a fundamental issue to integratively cluster a set of objects from multiple sources of datasets. Such problems are mostly encountered in genomics, where data is collected from various sources,…

Augmented block designs for unreplicated test treatments are investigated under the A- and MV-criteria with respect to control versus control, test versus test and control versus test comparisons. We derive design-independent lower bounds…

Statistics Theory · Mathematics 2023-10-31 Rahul Mukerjee

Copula models are flexible tools to represent complex structures of dependence for multivariate random variables. According to Sklar's theorem (Sklar, 1959), any d-dimensional absolutely continuous density can be uniquely represented as the…

Methodology · Statistics 2021-03-05 Clara Grazian , Luciana Dalla Valle , Brunero Liseo

Every design choice will have different effects on different units. However traditional A/B tests are often underpowered to identify these heterogeneous effects. This is especially true when the set of unit-level attributes is…

Artificial Intelligence · Computer Science 2016-11-09 Alexander Peysakhovich , Akos Lada

Copulas allow a flexible and simultaneous modeling of complicated dependence structures together with various marginal distributions. Especially if the density function can be represented as the product of the marginal density functions and…

Methodology · Statistics 2020-08-31 Jae Youn Ahn , Sebastian Fuchs , Rosy Oh

Under a mild condition we give closed-form expressions for copulas of systems that consist of maxima and of minima of subvectors of a given random vector $X$ with continuous marginals. Said expressions appear explicit in the copula of $X$…

Probability · Mathematics 2015-12-31 Matija Vidmar , Matjaž Omladič

Model selection is an important activity in modern data analysis and the conventional Bayesian approach to this problem involves calculation of marginal likelihoods for different models, together with diagnostics which examine specific…

Computation · Statistics 2008-10-31 David J. Nott , Robert J. Kohn , Mark Fielding

A meta-model of the input-output data of a computationally expensive simulation is often employed for prediction, optimization, or sensitivity analysis purposes. Fitting is enabled by a designed experiment, and for computationally expensive…

Methodology · Statistics 2023-12-01 Andrew Gill , David J. Warne , Antony M. Overstall , Clare McGrory , James M. McGree

Copulas are mathematical objects that fully capture the dependence structure among random variables and hence, offer a great flexibility in building multivariate stochastic models. In statistics, a copula is used as a general way of…

Methodology · Statistics 2013-10-01 Abhik Ghosh , Aritra Chakravorty

Given covariates for $n$ units, each of which is to receive a treatment with probability $1/2$, we study the question of how best to correlate their treatment assignments to minimize the variance of the IPW estimator of the average…

Methodology · Statistics 2025-01-08 Tim Morrison , Art B. Owen

In this paper we study a new model for patterns in two dimensions, inspired by diblock copolymer melts with a dominant phase. The model is simple enough to be amenable not only to numerics but also to analysis, yet sophisticated enough to…

Analysis of PDEs · Mathematics 2013-12-06 D. P. Bourne , M. A. Peletier , S. M. Roper

We consider the optimal design problem for identifying effective dose combinations within drug combination studies where the effect of the combination of two drugs is investigated. Drug combination studies are becoming increasingly…

This paper studies inference in randomized controlled trials with multiple treatments, where treatment status is determined according to a "matched tuples" design. Here, by a matched tuples design, we mean an experimental design where units…

Econometrics · Economics 2023-11-06 Yuehao Bai , Jizhou Liu , Max Tabord-Meehan

We build on theoretical results from the mechanism design literature to analyze empirical models of second-degree price discrimination (2PD). We show that for a random-coefficients discrete choice ("BLP") model to be suitable for studying…

General Economics · Economics 2025-10-03 Soheil Ghili , K. Sudhir , Nitish Jain , Ankur Garg

We develop a general variational inference method that preserves dependency among the latent variables. Our method uses copulas to augment the families of distributions used in mean-field and structured approximations. Copulas model the…

Machine Learning · Statistics 2015-11-03 Dustin Tran , David M. Blei , Edoardo M. Airoldi

For randomized clinical trials where a single, primary, binary endpoint would require unfeasibly large sample sizes, composite endpoints are widely chosen as the primary endpoint. Despite being commonly used, composite endpoints entail…

Methodology · Statistics 2022-09-27 Marta Bofill Roig , Guadalupe Gómez Melis , Martin Posch , Franz Koenig

A/B test, a simple type of controlled experiment, refers to the statistical procedure of experimenting to compare two treatments applied to test subjects. For example, many IT companies frequently conduct A/B tests on their users who are…

Methodology · Statistics 2026-05-12 Qiong Zhang , Lulu Kang

Row-column designs play an important role in applications where two orthogonal sources of error need to be controlled for by blocking. Field or greenhouse experiments, in which experimental units are arranged as a rectangular array of…

Methodology · Statistics 2025-11-26 Hans-Peter Piepho , Emlyn Williams

Implicit copulas are the most common copula choice for modeling dependence in high dimensions. This broad class of copulas is introduced and surveyed, including elliptical copulas, skew $t$ copulas, factor copulas, time series copulas and…

Methodology · Statistics 2021-09-13 Michael Stanley Smith

Randomisation is used in experimental design to reduce the prevalence of unanticipated confounders. Complete randomisation can however create unbalanced designs, for example, grouping all samples of the same condition in the same batch.…

Quantitative Methods · Quantitative Biology 2020-07-14 Bram Burger , Marc Vaudel , Harald Barsnes