An objective Bayes perspective on p ‐values
(Source: Biometrical Journal)
Source: Biometrical Journal - May 24, 2017 Category: Biotechnology Authors: Leonhard Held Tags: Short Communication Source Type: research
A spatially balanced design with probability function proportional to the within sample distance
The units observed in a biological, agricultural, and environmental survey are often randomly selected from a finite population whose main feature is to be geo‐referenced thus its spatial distribution should be used as essential information in designing the sample. In particular our interest is focused on probability samples that are well spread over the population in every dimension which in recent literature are defined as spatially balanced samples. To approach the problem we used the within sample distance as the summary index of the spatial distribution of a random selection criterion. Moreover numerical comparisons...
Source: Biometrical Journal - May 16, 2017 Category: Biotechnology Authors: Roberto Benedetti, Federica Piersimoni Tags: Research Paper Source Type: research
Contribution to the discussion of “A critical evaluation of the current ‘p‐value controversy’”
(Source: Biometrical Journal)
Source: Biometrical Journal - May 15, 2017 Category: Biotechnology Authors: Mauro Gasparini Tags: Short Communication Source Type: research
List of Reviewers for 2016
(Source: Biometrical Journal)
Source: Biometrical Journal - May 2, 2017 Category: Biotechnology Tags: List of Reviewers Source Type: research
Contents: Biometrical Journal 3'17
(Source: Biometrical Journal)
Source: Biometrical Journal - May 2, 2017 Category: Biotechnology Tags: Contents Source Type: research
Masthead: Biometrical Journal 3'17
(Source: Biometrical Journal)
Source: Biometrical Journal - May 2, 2017 Category: Biotechnology Tags: Masthead Source Type: research
Editorial Board: Biometrical Journal 3'17
(Source: Biometrical Journal)
Source: Biometrical Journal - May 2, 2017 Category: Biotechnology Tags: Editorial Board Source Type: research
Cover Picture: Biometrical Journal 3'17
(Source: Biometrical Journal)
Source: Biometrical Journal - May 2, 2017 Category: Biotechnology Tags: Cover Picture Source Type: research
Comparing dependent kappa coefficients obtained on multilevel data
Reliability and agreement are two notions of paramount importance in medical and behavioral sciences. They provide information about the quality of the measurements. When the scale is categorical, reliability and agreement can be quantified through different kappa coefficients. The present paper provides two simple alternatives to more advanced modeling techniques, which are not always adequate in case of a very limited number of subjects, when comparing several dependent kappa coefficients obtained on multilevel data. This situation frequently arises in medical sciences, where multilevel data are common. Dependent kappa c...
Source: Biometrical Journal - May 2, 2017 Category: Biotechnology Authors: Sophie Vanbelle Tags: Research Paper Source Type: research
Mixture model with multiple allocations for clustering spatially correlated observations in the analysis of ChIP ‐Seq data
Model‐based clustering is a technique widely used to group a collection of units into mutually exclusive groups. There are, however, situations in which an observation could in principle belong to more than one cluster. In the context of next‐generation sequencing (NGS) experiments, for example, the signal observed in the data might be produced by two (or more) different biological processes operating together and a gene could participate in both (or all) of them. We propose a novel approach to cluster NGS discrete data, coming from a ChIP‐Seq experiment, with a mixture model, allowing each unit to belong potentially...
Source: Biometrical Journal - May 1, 2017 Category: Biotechnology Authors: Saverio Ranciati, Cinzia Viroli, Ernst C. Wit Tags: Research Paper Source Type: research
Studying the relationship between a woman's reproductive lifespan and age at menarche using a Bayesian multivariate structured additive distributional regression model
Studies addressing breast cancer risk factors have been looking at trends relative to age at menarche and menopause. These studies point to a downward trend of age at menarche and an upward trend for age at menopause, meaning an increase of a woman's reproductive lifespan cycle. In addition to studying the effect of the year of birth on the expectation of age at menarche and a woman's reproductive lifespan, it is important to understand how a woman's cohort affects the correlation between these two variables. Since the behavior of age at menarche and menopause may vary with the geographic location of a woman's residence, t...
Source: Biometrical Journal - May 1, 2017 Category: Biotechnology Authors: Elisa Duarte, Bruno de Sousa, Carmen Cadarso ‐Suárez, Nadja Klein, Thomas Kneib, Vítor Rodrigues Tags: Research Paper Source Type: research
Multivariate binary classification of imbalanced datasets —A case study based on high‐dimensional multiplex autoimmune assay data
The classification of a population by a specific trait is a major task in medicine, for example when in a diagnostic setting groups of patients with specific diseases are identified, but also when in predictive medicine a group of patients is classified into specific disease severity classes that might profit from different treatments. When the sizes of those subgroups become small, for example in rare diseases, imbalances between the classes are more the rule than the exception and make statistical classification problematic when the error rate of the minority class is high. Many observations are classified as belonging t...
Source: Biometrical Journal - May 1, 2017 Category: Biotechnology Authors: Laura Schlieker, Anna Telaar, Angelika Lueking, Peter Schulz ‐Knappe, Carmen Theek, Katja Ickstadt Tags: Case Study Source Type: research
Fast precision estimation in high ‐dimensional multivariate joint models
A fast way is proposed based on the multiple outputation idea (Hoffman et al., ; Follmann et al., ) to calculate the precision of parameter estimates for high‐dimensional multivariate joint models using a pairwise approach (Fieuws and Verbeke, ; Fieuws et al., ). Simulation results as well as data analysis shows possibly more than 2500 times faster computations using the proposed method. In our real data illustration, the time gain is more than 330 times. (Source: Biometrical Journal)
Source: Biometrical Journal - May 1, 2017 Category: Biotechnology Authors: Vahid Nassiri, Anna Ivanova, Geert Molenberghs, Geert Verbeke Tags: Research Paper Source Type: research
Stratified exact tests for the weak causal null hypothesis in randomized trials with a binary outcome
Fisher's exact test is commonly used to compare two groups when the outcome is binary in randomized trials. In the context of causal inference, this test explores the sharp causal null hypothesis (i.e. the causal effect of treatment is the same for all subjects), but not the weak causal null hypothesis (i.e. the causal risks are the same in the two groups). Therefore, in general, rejection of the null hypothesis by Fisher's exact test does not mean that the causal risk difference is not zero. Recently, Chiba (Journal of Biometrics and Biostatistics 2015; 6: 244) developed a new exact test for the weak causal null hypothesi...
Source: Biometrical Journal - May 1, 2017 Category: Biotechnology Authors: Yasutaka Chiba Tags: Research Paper Source Type: research
Modern Adaptive Randomized Clinical Trials. O. Sverdlov (ed.) (2016). Boca Raton, FL: Chapman & Hall/CRC Press. 515 pages, ISBN: 978 ‐1‐4822‐3988‐1 (Hardback).
(Source: Biometrical Journal)
Source: Biometrical Journal - May 1, 2017 Category: Biotechnology Authors: Norbert Benda Tags: Book review Source Type: research
