On the hidden truncated bivariate Pareto (IV) model and associated inferential issues

Income and wealth data are typically modelled by some variant of the classical Pareto distribution. Often, in practice, the observed data are truncated with respect to some unobserved covariate. In this paper, a hidden truncation formulation of this scenario is proposed and analysed. For this purpose, a bivariate Pareto (IV) distribution is assumed for the variable of interest and the unobserved covariate. Some important distributional properties of the resulting model as well as associated inferential methods are studied. An example is used finally to illustrate the results developed here. In this case, it is noted that hidden truncation on the left does not result in any new model, but the hidden truncation on the right does. The properties and fit of such a model pose a challenging problem and that is what is focused here in this work.     

Adjusted Wilcoxon signed rank test tables for ratio of percentiles

The ordinary Wilcoxon signed rank test table provides confidence intervals for the median of one population. Adjusted Wilcoxon signed rank test tables which can provide confidence intervals for the median and the 10th percentile of one population are created in this paper. Base-(n + 1) number system and theorems about property of symmetry of the adjusted Wilcoxon signed rank test statistic are derived for programming. Theorem 1 states that the adjusted Wilcoxon signed rank test statistic are symmetric around n(n + 1)/4. Theorem 2 states that the adjusted Wilcoxon signed rank test statistic with the same number of negative ranks m are symmetric around m(n+1)/2. 87.5% and 85% confidence intervals of the median are given in the table for n = 12, 13,…, 29 to create approximated 95% confidence intervals of the ratio of medians for two independent populations. 95% and 92.5% confidence intervals of the 10th percentile are given in the table for n = 26, 27, 28, 29 to create approximated 95% confidence regions of the ratio of the 10th percentiles for two independent populations. Finally two large datasets from wood industry will be partitioned to verify the correctness of adjusted Wilcoxon signed rank test tables for small samples.     

Approximate confidence intervals for a linear combination of binomial proportions: A new variant

We propose a new adjustment for constructing an improved version of the Wald interval for linear combinations of binomial proportions, which addresses the presence of extremal samples. A comparative simulation study was carried out to investigate the performance of this new variant with respect to the exact coverage probability, expected interval length, and mesial and distal noncoverage probabilities. Additionally, we discuss the application of a criterion for interpreting interval location in the case of small samples and/or in situations in which extremal observations exist. The confidence intervals obtained from the new variant performed better for some evaluation measures.     

On a new positive dependence concept based on the conditional mean inactivity time order

In this paper, we introduce a new positive dependence concept between two non negative random variables which is related to a conditional version of the mean inactivity time order. A number of properties and relationship between the new notion and the concept of positive likelihood ratio dependence (PLRD) is discussed. Some results in terms of proposed notions for the Archimedean family of copulas are provided.     

The Population's Confidence in the Child Protection System – A Survey Study of England,Finland, Norway and the United States (California)

This article examines the confidence the population (N = 4,003) has in the child welfare system in four countries – England, Finland, Norway and the USA (California). We find that about half or less of the population reports having confidence in the system, which is slightly higher than the confidence in the civil servants in the same countries. The Nordic countries display more confidence in the child welfare system than the Anglo‐American countries. The similarity between the countries is, however, greater than anticipated. As for independent variables that can shed light on differences in confidence levels, we find three variables to be related to a higher confidence level, and these are a left wing political orientation, lower age, and higher education. This study contributes in filling a knowledge gap on studies about trust in the child welfare system, but we emphasize that we have studied an aspect of trust that rests on the population's impressions of a system, and not their substantial knowledge about, or identification with, this system.     

Nearly optimal covariate designs—Part I

We propose to discuss at length several examples from standard text books. All of these examples deal with analysis of covariance (ANCOVA) models and related analyses of data. We intend to capitalize on our understanding of optimal covariate designs (OCDs) in different ANCOVA models and re-visit these examples with a view to suggest optimal/nearly optimal designs for estimation of the covariate parameter(s). As we will see, for some examples our task is very much routine but for others, it is indeed a highly non trivial exercise.

?We intent to cover a total of six examples—divided in two parts. This is Part I—dealing with two examples.     

The effects of CSR communication in corporate crises: Examining the role of dispositional and situational CSR skepticism in context

Although consumer skepticism about corporate social responsibility (CSR) is on the rise, research is sparse on the psychological dynamics of this skepticism, particularly when CSR communication serves as a company’s crisis response strategy. Employing two between-subjects design experiments, this study aims to fill this gap by looking at the role consumer CSR skepticism plays in consumer reactions to CSR communications in different types of crises. The study 1 results show that dispositional CSR skepticism did not moderate the effect of crisis type on attitudes and intentions when CSR was used as a post-crisis response strategy. The study 2 findings, however, indicated that situational CSR skepticism significantly mediated the impact of crisis type and CSR motives on purchase intentions only when the crisis stemmed from some accidental rather than preventable circumstance. Theoretical and practical implications are discussed.