Search results for "Design"

Multiple sequence editing by spreadsheet.

1990

Spreadsheets have several functions and facilities that make them good candidates to be used as multiple sequence editors. They can be easily programmed (even by non-programmers) with macros that allow them to fit the needs of the user, free of the restrictions that programs written by other people have. Here I present a sheet containing a set of macros written for Lotus 1-2-3

Long-term experiments and strip plot designs

2015

In a long-term experiment usually the experimenter needs to know whether the effect of a treatment varies over time. But time usually has both a fixed and a random effects over the output and the difficulty in the analysis depends on the particular design considered and the availability of covariates. Actually, as shown in the paper, the presence of covariates can be very useful to model the random effect of time. In this paper a model to analyze data from a long-term strip plot design with covariates is proposed. Its effectiveness will be tested using both simulated and real data from a crop rotation experiment.

The Induced Smoothed lasso: A practical framework for hypothesis testing in high dimensional regression.

2020

This paper focuses on hypothesis testing in lasso regression, when one is interested in judging statistical significance for the regression coefficients in the regression equation involving a lot of covariates. To get reliable p-values, we propose a new lasso-type estimator relying on the idea of induced smoothing which allows to obtain appropriate covariance matrix and Wald statistic relatively easily. Some simulation experiments reveal that our approach exhibits good performance when contrasted with the recent inferential tools in the lasso framework. Two real data analyses are presented to illustrate the proposed framework in practice.

Bayesian Design of “Successful” Replications

2002

Replication of experiments is commonin applied research. However, systematic studies of the goals and motivations of a “replication” are rare. As a consequence, there does not seem to be a precise notion of what a “success” when replicating means. This article discusses some of the possible goals for replication; this leads to different (but precise) notions of “success” when replicating. Bayesian hierarchical models allow for a flexible and explicit incorporation of the assumed relationship among the experiments. Bayesian predictive distributions are a natural tool to compute the probability of the replication being successful, and hence to design the replication so that the probability of…

Achieving Unbounded Resolution inFinitePlayer Goore Games Using Stochastic Automata, and Its Applications

2012

Abstract This article concerns the sequential solution to a distributed stochastic optimization problem using learning automata and the Goore game (also referred to as the Gur game in the related literature). The amazing thing about our solution is that, unlike traditional methods, which need N automata (where N determines the degree of accuracy), in this article, we show that we can obtain arbitrary accuracy by recursively using only three automata. To be more specific, the Goore game (GG) introduced in Tsetlin (1973) has the fascinating property that it can be resolved in a completely distributed manner with no inter-communication between the players. The game has recently found applicati…

Reference Posterior Distributions for Bayesian Inference

1979

Robust Mean Field Games

2015

Recently there has been renewed interest in large-scale games in several research disciplines, with diverse application domains as in the smart grid, cloud computing, financial markets, biochemical reaction networks, transportation science, and molecular biology. Prior works have provided rich mathematical foundations and equilibrium concepts but relatively little in terms of robustness in the presence of uncertainties. In this paper, we study mean field games with uncertainty in both states and payoffs. We consider a population of players with individual states driven by a standard Brownian motion and a disturbance term. The contribution is threefold: First, we establish a mean field syste…

Bayesian longitudinal models for paediatric kidney transplant recipients

2015

Chronic kidney disease is a progressive loss of renal function which results in the inability of the kidneys to properly filter waste from the blood. Renal function is usually estimated by the glomerular filtration rate (eGFR), which decreases with the worsening of the disease. Bayesian longitudinal models with covariates, random effects, serial correlation and measurement error are discussed to analyse the progression of eGFR in first transplanted children taken from a study in Valencia, Spain.

Systematic handling of missing data in complex study designs : experiences from the Health 2000 and 2011 Surveys

2016

We present a systematic approach to the practical and comprehensive handling of missing data motivated by our experiences of analyzing longitudinal survey data. We consider the Health 2000 and 2011 Surveys (BRIF8901) where increased non-response and non-participation from 2000 to 2011 was a major issue. The model assumptions involved in the complex sampling design, repeated measurements design, non-participation mechanisms and associations are presented graphically using methodology previously defined as a causal model with design, i.e. a functional causal model extended with the study design. This tool forces the statistician to make the study design and the missing-data mechanism explicit…

Analysis of Educational Frequency Data from a Complex Sample Survey

1991

Abstract Some recent methods are presented for analyzing categorial data from complex surveys involving clustering familiar in educational research where e.g. teaching groups are used as sample clusters. The methods are introduced through a discussion of the test of independence on a two‐way table and the analysis of a two‐way table using logistic regression models. The analyses are illustrated using data from the First National Assessment of the Finnish Comprehensive School 1979. The primary focus of the paper is on the methods that provide first‐order corrections to standard multinomial‐based chi‐square tests by taking account of survey design effects. Both first‐ and second‐order correct…