A new class of estimators of finite population mean in sample surveys

This article suggests the class of estimators of population mean of study variable using various parameters related to an auxiliary variable with its properties in simple random sampling. It has been identified that the some existing estimator/classes of estimators are members of suggested class. It has been found theoretically as well as empirically that the suggested class is better than the existing methods.     

An adept-stratified Kuk's randomized response model using Neyman allocation

This paper suggests a new stratified randomized response model based on Kuk's [Biometrika (1990), 77, 2, pp.436–438] model that has Neyman allocation and considerable gain in precision. It has been identified that the stratified randomized response models due to Kim and Warde (2004 Kim, J., Warde, W. (2004). A stratified Warner randomized response model. J. Stat. Plan. Inference 120:155–165.[Crossref], [Web of Science ®] , [Google Scholar]), Kim and Elam's (2005), and Kim and Elam's (2007) are members of the proposed model. It is shown that the proposed model is more efficient than Kuk's (1990) model both theoretically and empirically. The results of this paper are also extended in the situation when trials are repeated.     

A new efficient unrelated randomized response model

The present paper suggests an interesting and useful ramification of the unrelated randomized response model due to Pal and Singh (2012 Pal, S., and S. Singh. 2012. A new unrelated question randomized response model. Statistics 46 (1):99–109.[Taylor &; Francis Online], [Web of Science ®] , [Google Scholar]) [A new unrelated question randomized response model. Statistics 46 (1), 99–109] that can be used for any sampling scheme. We have shown theoretically and numerically that the proposed model is more efficient than Pal and Singh (2012 Pal, S., and S. Singh. 2012. A new unrelated question randomized response model. Statistics 46 (1):99–109.[Taylor &; Francis Online], [Web of Science ®] , [Google Scholar]) model.     

Role models without guarantees: corrective representations and the cultural politics of a Latino male teacher in the borderlands

In recent years mentorship has become a popular ‘solution’ for struggling boys of color and has led to the recruitment of more male of color teachers. While not arguing against the merits of mentorship, this article critiques what the author deems ‘corrective representations.’ Corrective representations are the imagined embodiment of proper and productive masculinities that male of color educators are asked to perform. This discourse perpetuates confining representations of identity and locates the problem of boys of color within their own actions. Designed as an ethnographic case study, this article explores the life of one Latino male teacher as he navigates discourses of corrective representation as coordinator of his school’s Latino boys program. This project provides a detailed account of the cultural politics of Latino male mentorship and offers the notion of a critical borderlands approach to identity as an avenue to problematize essentialist and deficit approaches to Latino boys.     

A modified two-stage randomized response model for estimating the proportion of stigmatized attribute

The survey related to stigmatized characteristics leads to the non-response problem if it is conducted according to classical (direct) methods, especially, developed for non-sensitive issues; therefore, it needs to be applied appropriate survey methodology to get a reliable response from respondents in incriminating issues. Randomized response model is one of the most recent methods which is attracting the attention of survey practitioners to deal with the problems of non-response because it protects the privacy of individuals in order to acquire the truthful response. The present work proposes a new two-stage randomized response model to get rid of misleading response or non-response due to the stigmatized nature of attribute under the study. The proposed randomized response model results in the unbiased estimator of population proportion possessing the sensitive attribute. The properties of the resultant estimator have been studied and empirical comparisons are performed to show its dominance over existing estimators. Suitable recommendations have been put forward to the survey practitioners.     

Hadedas in the hood: Hadeda Ibis activity in suburban neighbourhoods of Pietermaritzburg,KwaZulu-Natal,South Africa

Urban environments are a combination of green and grey spaces and although many species are unable to live in these transformed areas there are some that can use urban features to benefit their persistence here. The Hadeda Ibis (Bostrychia hagedash) is one such species and this study investigated the urban activities of these birds. Five suburbs of Pietermaritzburg in KwaZulu-Natal, South Africa were surveyed for Hadeda Ibis engaged in flying, foraging, perching and calling behaviours. Each suburb differed in the degree of urbanisation and we expected that their morning activity would differ accordingly. A difference in Hadeda Ibis calling, foraging and flying activity between summer and winter was also expected because of seasonal rainfall patterns. Although Hadeda Ibis were more common in suburbia than the city centre in Pietermaritzburg, they occurred throughout. More were observed calling in summer than in winter probably because of changes in distribution during the breeding season with more family groups of two or three individuals. There was no significant difference in Hadeda Ibis flock size when comparing foraging during summer with winter despite greater summer rainfall. Also there was no significant difference in flock size with flying activity for both seasons nor suburb although it was expected that Hadeda Ibis would need to travel further during winter and from suburbs with more grey space to access ideal foraging areas. Hadeda Ibis need moist soil to forage effectively and in an urban environment short grassed, well watered lawns provided an ideal foraging habitat regardless of season. Hadeda Ibis used urban structures like house roofs, poles, pylons, and fences for perching but continued to roost in trees so while they are able to use urban features, they still rely on a certain degree of green space for urban persistence.     

Some calibration estimators for finite population mean in two-stage stratified random sampling

Abstract

In the present article, an effort has been made to develop calibration estimators of the population mean under two-stage stratified random sampling design when auxiliary information is available at primary stage unit (psu) level. The properties of the developed estimators are derived in-terms of design based approximate variance and approximate consistent design based estimator of the variance. Some simulation studies have been conducted to investigate the relative performance of calibration estimator over the usual estimator of the population mean without using auxiliary information in two-stage stratified random sampling. Proposed calibration estimators have outperformed the usual estimator without using auxiliary information.     

Dynamic relationships between children’s higher‐order regulation and lower‐order reactivity predict development of attention problems

Dual‐process theories contend that interplay between higher‐order (i.e., regulatory) and lower‐order (i.e., reactive) systems influences the development of attention in early childhood. We therefore investigated interactions between an aspect of children's top‐down self‐regulation (i.e., effortful control; EC) and positive reactivity (indexed by observed positive affectivity; PA) and negative reactivity (indicated by cortisol stress reactivity and observed fear) in predicting children's early attention problems. We found that observed EC at the age of three predicted lower attention problems 2 years later, controlling for attention problems at baseline. Importantly, the predictive effect of EC was more pronounced for children higher in cortisol stress reactivity at the age of three; this pattern was not found for observed PA or fear. Findings align with dual‐process developmental theories that emphasize the dynamics between regulatory and reactive processes in shaping child development. Our study provides the first evidence supporting dual‐process interactions in the domain of attention problems and has implications for identifying early risk markers and informing early prevention programs for children at greater risk for attention problems.     

A two-stage unrelated randomized response model for estimating a rare sensitive attribute in probability proportional to size sampling using Poisson distribution

This paper describes the estimating procedures of mean number of entities that possess a rare sensitive attribute using the Mangat (1992) randomized device, when the population consists of some clusters and the population is again stratified with some clusters in each stratum. Unbiased estimation procedures for the mean number of individuals have been discussed and their properties are described when the parameter of a rare unrelated attribute is assumed to be known and unknown. An empirical study is carried out to show the dominance of the proposed estimator over Lee et al. (2013) estimator.