Search results for "Multivariate Analysi"

Factors influencing inclusion in digestive cancer clinical trials: A population-based study

2015

Inclusion in a randomized therapeutic trial represents an optimal therapeutic strategy.To determine the influence of demographic characteristics and deprivation on the enrolment of patients in digestive cancer clinical trials.Between 2004 and 2010, 4632 patients were recorded by the Burgundy Digestive Cancer Registry. According to a balancing score, the 136 patients included in a clinical trial were matched with 272 patients who met the eligibility criteria for trials. Deprivation was measured by the ecological European deprivation index. A conditional multivariate logistic regression was performed.Patients aged over 75 years were significantly less likely to be included in clinical trials …

Collecting large cohorts of patients with uncommon diseases: mission impossible?

2007

Generation of hierarchically correlated multivariate symbolic sequences: With an application to the assessment of bootstrap confidence in phylogeneti…

2008

We introduce a method to generate multivariate series of symbols from a finite alphabet with a given hierarchical structure of similarities based on the Hamming distance. The target hierarchical structure of similarities is arbitrary, for instance the one obtained by some hierarchical clustering method applied to an empirical matrix of similarities. The method that we present here is based on a generating mechanism that does not make use of mutation rate, which is widely used in phylogenetic analysis. Here we use the proposed simulation method to investigate the relationship between the bootstrap value associated with a node of a phylogeny and the probability of finding that node in the tru…

Computational issues in fitting joint frailty models for recurrent events with an associated terminal event.

2020

Abstract Background and objective: Joint frailty regression models are intended for the analysis of recurrent event times in the presence of informative drop-outs. They have been proposed for clinical trials to estimate the effect of some treatment on the rate of recurrent heart failure hospitalisations in the presence of drop-outs due to cardiovascular death. Whereas a R-software-package for fitting joint frailty models is available, some technical issues have to be solved in order to use SASⓇ 1 software, which is required in the regulatory environment of clinical trials. Methods: First, we demonstrate how to solve these issues by deriving proper likelihood-decompositions, in particular fo…

Design of composite measure schemes for comparative severity assessment in animal-based neuroscience research: A case study focussed on rat epilepsy …

2020

PLOS ONE 15(5), e0230141 (2020). doi:10.1371/journal.pone.0230141

Information-based detection of nonlinear Granger causality in multivariate processes via a nonuniform embedding technique

2010

We present an approach, framed in information theory, to assess nonlinear causality between the subsystems of a whole stochastic or deterministic dynamical system. The approach follows a sequential procedure for nonuniform embedding of multivariate time series, whereby embedding vectors are built progressively on the basis of a minimization criterion applied to the entropy of the present state of the system conditioned to its past states. A corrected conditional entropy estimator compensating for the biasing effect of single points in the quantized hyperspace is used to guarantee the existence of a minimum entropy rate at which to terminate the procedure. The causal coupling is detected acc…

Patterns of genetic and phenotypic variation in Iris haynei and I. atrofusca (Iris sect. Oncocyclus = the royal irises) along an ecogeographical grad…

2002

Iris haynei and I. atrofusca are two closely related narrow endemics distributed vicariously along an ecogeographical north-south gradient in Israel and the West Bank. To obtain baseline information of the taxonomic status, conservation and population history of these taxa, we investigated patterns of phenotypic variation and the partitioning of genetic variation within and among populations using dominant random amplified polymorphic DNA (RAPD) markers. Multivariate (principal components analysis) and taxonomic distance analyses based on morphometric traits from eight populations revealed no unambiguous separation into two distinct groups. Results of genetic analyses for nine populations d…

Household Expenditure on Leisure: a Comparative Study of Italian Households with Children from Y- and Z-Generation

2019

The intrinsic complexity of post-materialist society makes it challenging to investigate the connection between social changes and generations. However, the study of consumption might help in the analysis of such a connection. In this paper, we analyse empirical data of consumption on leisure of Italian households, and focus on families at a very precise stage of family life-cycle, that is, couples with teenager children. We look at consumption of households at different points in time, 2001, 2007, and 2012, in order to investigate the impact of both social change and generation of children–Y-generation in 2001 and 2007, and Z-generation in 2012–on the leisure expenditure patterns of famili…

To Pay or Not to Pay: Competing Theories to Explain Individuals’ Willingness to Pay for Public Environmental Goods

2010

Dieser Beitrag ist mit Zustimmung des Rechteinhabers aufgrund einer (DFG geförderten) Allianz- bzw. Nationallizenz frei zugänglich. This publication is with permission of the rights owner freely accessible due to an Alliance licence and a national licence (funded by the DFG, German Research Foundation) respectively. Several theories have been proposed in an attempt to explain individuals’ willingness to pay (WTP) for public environmental goods. While most studies only take into account a single theory, this article discusses competing theories. These include, in addition to a basic economic model, the theory of public goods, Ajzen’s theory of planned behavior, and Schwartz’s norm-activation…

The Relation Between Maternal Locus of Control And Coping Styles of Pediatric Leukemia Patients During Treatment

2020

The present study focuses on the relation between coping strategies of children with leukemia during treatment and locus of control of their mothers. In particular, the study aims to determine whether maternal locus of control can influence sick children’s coping styles, and if this relation can be used to predict maladjustments. The study analyzed a cohort of 60 pediatric leukemia patients undergoing treatment and a group formed by their mothers. The participants were recruited from two Pediatric Onco- Hematology Units in Italy. The Child Behavioral Style Scale (CBSS) was used to assess children’s coping strategies, whereas the Parental Health Locus of Control Scale (PHLCS) was employed to…