Search results for " hypothesis"
showing 10 items of 371 documents
Inference for the interclass correlation in familial data using small sample asymptotics
2012
Inference on the parent-offspring correlation coefficient is an important problem in the analysis of familial data, and point estimates and likelihood based inference are available in the literature. In this work, corrections for the signed log-likelihood ratio test statistics are proposed, based on small sample asymptotics, in order to achieve accurate small sample performance. The corrected statistic can be used for hypothesis testing as well as for interval estimation.
Testosterone and cortisol release among Spanish soccer fans watching the 2010 World Cup Final
2012
This field study investigated the release of testosterone and cortisol of a vicarious winning experience in Spanish fans watching the finals between Spain and the Netherlands in the 2010 FIFA World Cup Soccer. Spanish fans (n = 50) watched the match with friends or family in a public place or at home and also participated in a control condition. Consistent with hypotheses, results revealed that testosterone and cortisol levels were higher when watching the match than on a control day. However, neither testosterone nor cortisol levels increased after the victory of the Spanish team. Moreover, the increase in testosterone secretion was not related to participants' sex, age or soccer fandom, b…
Stress as a Key Concept in Chronic Widespread Pain and Fatigue Disorders
2009
ABSTRACT.Objectives: To review recent studies on the etiopathogenetic role and clinical relevance of life stress in medically unexplained syndromes characterized by chronic widespread musculoskeletal pain and fatigue.Findings: Both fibromyalgia syndrome [FMS] and chronic fatigue syndrome [CFS] have been found to be frequently linked to different stressors, such as negative life events, occupational problems, posttraumatic stress [PTSD], adverse childhood experiences, and “overactive” lifestyle. In addition, the stress-modulating role of affect-regulation, perceptual-cognitive factors, and social support, as well as the relationship with depression have been investigated in FMS/CFS patients.…
Incomplete Riemann Solvers Based on Functional Approximations to the Absolute Value Function
2021
We give an overview on the work developed in recent years about certain classes of incomplete Riemann solvers for hyperbolic systems. These solvers are based on polynomial or rational approximations to |x|, and they do not require the knowledge of the complete eigenstructure of the system, but only a bound on the maximum wave speed. Our solvers can be readily applied to nonconservative hyperbolic systems, by following the theory of path-conservative schemes. In particular, this allows for an automatic treatment of source or coupling terms in systems of balance laws. The properties of our schemes have been tested with some challenging numerical experiments involving systems such as the Euler…
Mens sana in corpore exhausto. Emociones y gestión de sí en escuelas secundarias del sur global
2020
In recent years, emotional education has become a central element in a series of guidelines on a global scale that have been translated into various state initiatives aimed at education. Thus, Mens sana in corpore exhausto proposes to demonstrate the tension that is expressed between the growing series of discourses on emotional education and the school climate and the exhaustive bodies of teachers and directors of public secondary schools in the Metropolitan Region of Buenos Aires (RMBA). By way of hypothesis, these policies are considered to work on the bodies of teachers and directors, encouraging them to continue and not stop under the logic of management and self-management that throw …
Analysis of eta production using a generalized Lee model
1998
We have investigated the processes N($\pi$, $\pi$)N and N($\pi$, $\eta$)N close to eta threshold using a simple, nonrelativistic Lee model which has the advantage of being analytically solvable. It is then possible to study the Riemann sheets of the S-matrix and the behavior of its resonance poles especially close to threshold. A theoretical simulation of the experimental cusp effect at eta threshold leads to a characteristic distribution of poles on the Riemann sheets. We find a pole located in the $4^{th}$ Riemann sheet that up to now has not been discussed. It belongs to the cusp peak at eta threshold. In addition we obtain the surprising result using the Lee model that the resonance $S_…
New Author Guidelines for Displaying Data and Reporting Data Analysis and Statistical Methods in Experimental Biology
2019
The American Society for Pharmacology and Experimental Therapeutics has revised the Instructions to Authors for Drug Metabolism and Disposition, Journal of Pharmacology and Experimental Therapeutics, and Molecular Pharmacology These revisions relate to data analysis (including statistical analysis) and reporting but do not tell investigators how to design and perform their experiments. Their overall focus is on greater granularity in the description of what has been done and found. Key recommendations include the need to differentiate between preplanned, hypothesis-testing, and exploratory experiments or studies; explanations of whether key elements of study design, such as sample size and …
Comparing normal means: new methods for an old problem
2007
Comparing the means of two normal populations is an old problem in mathematical statistics, but there is still no consensus about its most appropriate solution. In this paper we treat the problem of comparing two normal means as a Bayesian decision problem with only two alternatives: either to accept the hypothesis that the two means are equal, or to conclude that the observed data are, under the assumed model, incompatible with that hypothesis. The combined use of an information-theory based loss function, the intrinsic discrepancy (Bernardo and Rueda 2002}, and an objective prior function, the reference prior \citep{Bernardo 1979; Berger and Bernardo 1992), produces a new solution to this…
A ML Estimator of the Correlation Dimension for Left-hand Truncated Data Samples
2002
— A maximum-likelihood (ML) estimator of the correlation dimension d 2 of fractal sets of points not affected by the left-hand truncation of their inter-distances is defined. Such truncation might produce significant biases of the ML estimates of d 2 when the observed scale range of the phenomenon is very narrow, as often occurs in seismological studies. A second very simple algorithm based on the determination of the first two moments of the inter-distances distribution (SOM) is also proposed, itself not biased by the left-hand truncation effect. The asymptotic variance of the ML estimates is given. Statistical tests carried out on data samples with different sizes extracted from populatio…
Exploring theoretical frameworks for the analysis of fertility fluctuations
1988
The Easterlin theory, popular during the 1970s, explained population fluctuations in terms of maximization of choice, based on the evaluation of previously acquired information. Fluctuations in procreational patterns were seen as responses to conflict between 2 consecutive generations in which the propensity to procreate is inversely related to cohort size. However, the number of demographic trends not directly explainable by the hypothesis imply that either the model must be extended over a longer time frame or that there has been a drastic change of regime, i.e., a basic change in popular attitudes which determine decision making behavior. 4 strategic principles underlie reproductive deci…