Estimating the reliability of repeatedly measured endpoints based on linear mixed‐effects models. A tutorial

There are various settings in which researchers are interested in the assessment of the correlation between repeated measurements that are taken within the same subject (i.e., reliability). For example, the same rating scale may be used to assess the symptom severity of the same patients by multiple physicians, or the same outcome may be measured repeatedly over time in the same patients. Reliability can be estimated in various ways, for example, using the classical Pearson correlation or the intra‐class correlation in clustered data. However, contemporary data often have a complex structure that goes well beyond the restrictive assumptions that are needed with the more conventional methods to estimate reliability. In the current paper, we propose a general and flexible modeling approach that allows for the derivation of reliability estimates, standard errors, and confidence intervals – appropriately taking hierarchies and covariates in the data into account. Our methodology is developed for continuous outcomes together with covariates of an arbitrary type. The methodology is illustrated in a case study, and a Web Appendix is provided which details the computations using the R package CorrMixed and the SAS software. Copyright © 2016 John Wiley & Sons, Ltd.     

Pers?nlichkeits��bereinstimmungen zwischen Marke und Konsument: Stand der empirischen Selbstkongruenzforschung und verbleibende Investigationsdirektiven

Great importance is attached to the perception of personality matches between brand and consumers regarding its impact on purchase behaviour and purchase behaviour antecedents. The latest metaanalysis of Bauer et al. (2006) confirmed the high level of significance of selfcongruity effects but drew also attention to the moderate level of the average total effects whose reasons are still unexplored. In particular selfcongruity research lacks knowledge about the relevance of physical self congruity perceptions that may enhance traditionally moderate levels of self congruity effects if included in self congruity measures. Additionally possible tracks of implementing selfcongruity research findings in practice are still unexplored. As knowledge of how to force selfcongruity perceptions is missing, yet the application of selfcongruity theory is subjected to trial-and-error-principles. This article dedicates to the actual state of the selfcongruity research that has not been systematised extensively since the nineteen-eighties. Existing metaanalytical results are supplemented by deepening theoretical knowledge of complementary areas of research. The resulting synthesis leads to an interdisciplinary comprehension of self congruity effects. On the basis of these explanations detailed findings are provided concerning research directives that still necessitate investigation: research in levels of self congruity effects as well as research in possibilities of implementing self congruity knowledge in daily brand management.     

The two-sample <Emphasis Type="Italic">t</Emphasis> test: pre-testing its assumptions does not pay off

Traditionally, when applying the two-sample t test, some pre-testing occurs. That is, the theory-based assumptions of normal distributions as well as of homogeneity of the variances are often tested in applied sciences in advance of the tried-for t test. But this paper shows that such pre-testing leads to unknown final type-I- and type-II-risks if the respective statistical tests are performed using the same set of observations. In order to get an impression of the extension of the resulting misinterpreted risks, some theoretical deductions are given and, in particular, a systematic simulation study is done. As a result, we propose that it is preferable to apply no pre-tests for the t test and no t test at all, but instead to use the Welch-test as a standard test: its power comes close to that of the t test when the variances are homogeneous, and for unequal variances and skewness values |γ ₁| < 3, it keeps the so called 20% robustness whereas the t test as well as Wilcoxon’s U test cannot be recommended for most cases.     

Weighted Logrank Permutation Tests for Randomly Right Censored Life Science Data

In biomedical research, weighted logrank tests are frequently applied to compare two samples of randomly right censored survival times. We address the question how to combine a number of weighted logrank statistics to achieve good power of the corresponding survival test for a whole linear space or cone of alternatives, which are given by hazard rates. This leads to a new class of semiparametric projection tests that are motivated by likelihood ratio tests for an asymptotic model. We show that these tests can be carried out as permutation tests and discuss their asymptotic properties. A simulation study together with the analysis of a classical data set illustrates the advantages.     

道德价值与其他价值

道德价值与反道德价值之间的区别产生自特定道德之内，而道德价值与非道德价值之间的区别产生自一种超越了一切特定道德视角的理论视角。对道德价值的独特本性的语言学的、心理学的和社会学的探索等间接探索方式所带来的麻烦是循环论证，即它们全都预设人们已知道德是什么。而康德式的直接探索（元伦理学与规范伦理学的交混）所带来的麻烦是，它所产出的是理想化概念而非工作性概念，不适应于道德价值的多变的和多元的现实。道德价值的普遍性比一般性弱，但比一致性强。普遍性原则远非普遍有效。道德价值在人们的价值体系中并不必然是至上的，而可能拥有一种相对弱势的地位。道德评价应当循着价值连续统而非对错好坏的二元对立而进行。具体情境中的道德选择的准则不是绝对的，而是在一定程度上相对的。