True endpoint reduction by surrogate endpoints

The use of surrogate endpoint, which is becoming widely popular now a days, was introduced in medical research to reduce the time of experiment required for the approval of a drug. Through cost cutting and time saving, the surrogate endpoints can bring profit to the medicine producers. We obtain the expression for the reduction of true samples, in proportion, at an expense of surrogates to achieve a fixed power while comparing the two treatments. We present our discussion in the two-treatment set up in the context of odds ratio as a measure of treatment difference. We illustrate the methodology with some real dataset.     

On the distribution of a second degree polynomial statistic in singular normal var1aies

This note provides an alternative proof of a basic theorem on the distribution of a second degree polynomial statistic in noncentral singular normal variates originally proven by Rayner and Livingstone (1965)     

Self-reported Use of Emotional Display Rules in the Netherlands and Iran: Evidence for Sociocultural Influence

Sociocultural differences in children's use and understanding of emotional display rules have been under-researched. In the present study, 56 Dutch and 56 Iranian children aged 10–11 years took part in a structured interview about their experiences of using emotional display rules. In comparison with the Dutch children, the Iranian sample was more likely to report having actually used emotional display rules themselves, more likely to identify family audiences for display rules, and less likely to identify peer audiences. In addition, they were more likely than the Dutch children to identify both prosocial and self-protective motives for concealing emotion from family audiences, and less likely to identify self-protective motives for concealing emotion from peers. Results are interpreted in the light of socialization processes involved in the development of emotion regulation.     

Identity tensions of women with two leadership positions in India

Identity narratives enhance the understanding of women’s leadership, but there exist very few in-depth analyses of negative identity tensions that influence agency. In this study, we examine the negative identity tensions of well-to-do women from small towns in India, who hold two leadership positions: organizational and social movement. We borrow from the discourse on well-to-do women’s participation in social movements in India to draw on the notions of identity, perceptions of feminism, and patriarchal challenge. Our data are derived from 49 in-depth interviews with women leaders. Findings from qualitative analysis and creation of a composite narrative show that negative identity tensions arising from two leadership positions are gendered in nature. Furthermore, agency is (i) contingent on one’s reflection on challenges, (ii) rooted in an underlying principle, and (iii) practiced through the mechanisms of “managing femininity,” a concept that is widely discussed in the Western paradigms of postfeminism and neoliberalism. This paper contributes to the feminist dialog on the global South in the context of gender, class, and geographical location intersection by revealing certain non-Western ways of managing femininity. However, in the process, the hegemony of Indian men remains intact.     

Order-free co-regionalized areal data models with application to multiple-disease mapping

With the ready availability of spatial databases and geographical information system software, statisticians are increasingly encountering multivariate modelling settings featuring associations of more than one type: spatial associations between data locations and associations between the variables within the locations. Although flexible modelling of multivariate point-referenced data has recently been addressed by using a linear model of co-regionalization, existing methods for multivariate areal data typically suffer from unnecessary restrictions on the covariance structure or undesirable dependence on the conditioning order of the variables. We propose a class of Bayesian hierarchical models for multivariate areal data that avoids these restrictions, permitting flexible and order-free modelling of correlations both between variables and across areal units. Our framework encompasses a rich class of multivariate conditionally autoregressive models that are computationally feasible via modern Markov chain Monte Carlo methods. We illustrate the strengths of our approach over existing models by using simulation studies and also offer a real data application involving annual lung, larynx and oesophageal cancer death-rates in Minnesota counties between 1990 and 2000.     

Flexible Cure Rate Modeling Under Latent Activation Schemes

With rapid improvements in medical treatment and health care, many datasets dealing with time to relapse or death now reveal a substantial portion of patients who are cured (i.e., who never experience the event). Extended survival models called cure rate models account for the probability of a subject being cured and can be broadly classified into the classical mixture models of Berkson and Gage (BG type) or the stochastic tumor models pioneered by Yakovlev and extended to a hierarchical framework by Chen, Ibrahim, and Sinha (YCIS type). Recent developments in Bayesian hierarchical cure models have evoked significant interest regarding relationships and preferences between these two classes of models. Our present work proposes a unifying class of cure rate models that facilitates flexible hierarchical model-building while including both existing cure model classes as special cases. This unifying class enables robust modeling by accounting for uncertainty in underlying mechanisms leading to cure. Issues such as regressing on the cure fraction and propriety of the associated posterior distributions under different modeling assumptions are also discussed. Finally, we offer a simulation study and also illustrate with two datasets (on melanoma and breast cancer) that reveal our framework's ability to distinguish among underlying mechanisms that lead to relapse and cure.     

Recursive and Sequential Tests of the Unit-Root and Trend-Break Hypotheses: Theory and International Evidence

This article investigates the possibility, raised by Perron and by Rappoport and Reichlin, that aggregate economic time series can be characterized as being stationary around broken trend lines. Unlike those authors, we treat the break date as unknown a priori. Asymptotic distributions are developed for recursive, rolling, and sequential tests for unit roots and/or changing coefficients in time series regressions. The recursive and rolling tests are based on changing subsamples of the data. The sequential statistics are computed using the full data set and a sequence of regressors indexed by a “break” date. When applied to data on real postwar output from seven Organization for Economic Cooperation and Development countries, these techniques fail to reject the unit-root hypothesis for five countries (including the United States) but suggest stationarity around a shifted trend for Japan.     

Voice Cues Influence Children’s Assessment of Adults’ Occupational Competence

Journal of Nonverbal Behavior - The adult voice is a strong bio-social marker for masculinity and femininity. In this study we investigated whether children make gender stereotypical judgments...     

A MONETARY BUSINESS CYCLE MODEL FOR INDIA

A New Keynesian monetary business cycle model is constructed to study why monetary transmission in India is weak. Our models feature banking and financial sector frictions as well as an informal sector. The predominant channel of monetary transmission is a credit channel. Our main finding is that base money shocks have a larger and more persistent effect on output than an interest rate shock, as in the data. The presence of an informal sector hinders monetary transmission. Contrary to the consensus view, financial repression in the form of a statutory liquidity ratio and administered interest rates, does not weaken monetary transmission. (JEL E31, E32, E44, E52, E63)