On the comparison of Horvitz–Thompson and Murthy's sampling strategies for estimating finite population proportions in direct and randomized response surveys

We consider the problem of unbiased estimation of a finite population proportion and compare the relative efficiency of the unequal probability sampling strategies due to Horvitz and Thompson (1952 Horvitz, D.G., Thompson, D.J. (1952). A generalization of sampling without replacement. J Am Stat Assoc. 47:663–685.[Taylor &; Francis Online], [Web of Science ®] , [Google Scholar]) and Murthy (1957 Murthy, M.N. (1957). Ordered and unordered estimators in sampling without replacement. Sankhya 18:379–390. [Google Scholar]) under a super-population model. It is shown that the model expected variance is smaller for the Murthy's (1957 Murthy, M.N. (1957). Ordered and unordered estimators in sampling without replacement. Sankhya 18:379–390. [Google Scholar]) strategy both when these two sampling strategies are based on data obtained from (i) a direct survey, and (ii) a randomized response (RR) survey employing some RR technique following a general RR model.     

Regression for doubly inflated multivariate Poisson distributions

Dependent multivariate count data occur in several research studies. These data can be modelled by a multivariate Poisson or Negative binomial distribution constructed using copulas. However, when some of the counts are inflated, that is, the number of observations in some cells are much larger than other cells, then the copula-based multivariate Poisson (or Negative binomial) distribution may not fit well and it is not an appropriate statistical model for the data. There is a need to modify or adjust the multivariate distribution to account for the inflated frequencies. In this article, we consider the situation where the frequencies of two cells are higher compared to the other cells and develop a doubly inflated multivariate Poisson distribution function using multivariate Gaussian copula. We also discuss procedures for regression on covariates for the doubly inflated multivariate count data. For illustrating the proposed methodologies, we present real data containing bivariate count observations with inflations in two cells. Several models and linear predictors with log link functions are considered, and we discuss maximum likelihood estimation to estimate unknown parameters of the models.     

Assessment of systemic greenness: a case study of tyre manufacturing unit

Abstract

In this paper, we develop an assessment framework to evaluate the systemic greenness of a tyre manufacturing unit by capturing the interactions between the green practices implemented. By reviewing the existing literature, we propose a stakeholder-based green practices framework comprising of operation strategy practices, process practices, employee practices, regulatory practices, customer practices, competition practices, social practices, and supplier practices. The empirical data on the interactions of green practices between and within stakeholders are collected by conducting a detailed case study of a large radial tyre manufacturing unit in India. We use graph-theoretic approach to incorporate the interactions between different green practices and assess the systemic greenness of the case organisation. Based on the systemic greenness attained, we rank the green practices within stakeholders and also between the stakeholders. We conduct scenario analysis to develop a systemic greenness index and a scale to assist practitioners in evaluating and benchmarking the greenness performance. We also discuss implications for theory and practice along with the inherent limitations.     

Participant Supervision: Supervisor and Supervisee Experiences of Cotherapy

Participant supervision is a unique application of live supervision in which a supervisor and supervisee see clients conjointly. Although minimally discussed in the family therapy literature, it has notable advantages, chief among them being a shared clinical experience that increases attunement to supervisee skill and development, the modeling of skillful intervention, and a higher degree of collegiality. However, it is not without its challenges, including supervisee vulnerability and anxiety, diffusion of responsibility, and limited time for case discussion. This article highlights the experience of one supervisor and three doctoral‐level supervisees engaging in participant supervision over the course of a 2‐year period. Using illustrative examples, we discuss our experience of the advantages and challenges of participant supervision, and provide recommendations for establishing a collaborative relational context within which supervisory benefits can be maximized.     

Bird species assemblages across a rural urban gradient around Kolkata,India

Urban development leads to changes in habitat structure and resource base. Bird communities are known to respond sharply to such changes. Our result from study of bird community along urbanization gradient around Kolkata metropolitan city clearly separated the urban bird community from the rural and rural 3 habitats in terms of species diversity and foraging groups. Rural and rural 3 sites had more number of rare species and higher percentage of unique species as compared to the urban habitats. Functional group analysis showed higher abundance of granivores in urban habitats and absence of insectivore and carnivorous species that were found in the rural and rural 3 habitats. The bird species assemblage along the gradient was significantly nested where bird species recorded in urban areas were subset of the species rich rural areas. There was no difference in individual counts between urban and rural habitats, therefore nullifying the hypothesis that rural areas are more species rich because of higher population size. Bird community in the urban areas was less even as compared to the rural areas due to the dominance of omnivorous guild. Bird diversity was negatively correlated to the density of house lots.     

Modelling multi-stage processes through multivariate distributions

A new model combining parametric and semi-parametric approaches and following the lines of a semi-Markov model is developed for multi-stage processes. A Bivariate sojourn time distribution derived from the bivariate exponential distribution of Marshall & Olkin (1967) is adopted. The results compare favourably with the usual semi-parametric approaches that have been in use. Our approach also has several advantages over the models in use including its amenability to statistical inference. For example, the tests for symmetry and also for independence of the marginals of the sojourn time distributions, which were not available earlier, can now be conveniently derived and are enhanced in elegant forms. A unified Goodness-of-Fit test procedure for our proposed model is also presented. An application to the human resource planning involving real-life data from University of Nigeria is given.     

A Bayesian analysis of the change-point problem for directional data

In this paper, we discuss a simple fully Bayesian analysis of the change-point problem for the directional data in the parametric framework with von Mises or circular normal distribution as the underlying distribution. We first discuss the problem of detecting change in the mean direction of the circular normal distribution using a latent variable approach when the concentration parameter is unknown. Then, a simpler approach, beginning with proper priors for all the unknown parameters – the sampling importance resampling technique – is used to obtain the posterior marginal distribution of the change-point. The method is illustrated using the wind data [E.P. Weijers, A. Van Delden, H.F. Vugts and A.G.C.A. Meesters, The composite horizontal wind field within convective structures of the atmospheric surface layer, J. Atmos. Sci. 52 (1995. 3866–3878]. The method can be adapted for a variety of situations involving both angular and linear data and can be used with profit in the context of statistical process control in Phase I of control charting and also in Phase II in conjunction with control charts.     

Unbiased Estimation of P(X > Y) for Exponential Populations Using Order Statistics with Application in Ranked Set Sampling

This paper addresses the problem of unbiased estimation of P[X > Y] = θ for two independent exponentially distributed random variables X and Y. We present (unique) unbiased estimator of θ based on a single pair of order statistics obtained from two independent random samples from the two populations. We also indicate how this estimator can be utilized to obtain unbiased estimators of θ when only a few selected order statistics are available from the two random samples as well as when the samples are selected by an alternative procedure known as ranked set sampling. It is proved that for ranked set samples of size two, the proposed estimator is uniformly better than the conventional non-parametric unbiased estimator and further, a modified ranked set sampling procedure provides an unbiased estimator even better than the proposed estimator.     

Anna Hazare's Anti-Corruption Movement and the Limits of Mass Mobilization in India

A hunger strike that played upon Gandhi's legacy of civil disobedience and mass protest was India's capstone event for 2011. Initiated by Anna Hazare, a 74-year-old self-styled Gandhian, the protest targeted the government's new anti-corruption legislation, which Hazare proclaimed as too weak. Hazare's demand for a strong anti-corruption law, leading to the establishment of an independent ombudsman (Lokpal), had slowly gained momentum in the first half of 2011, when Hazare collected a sizeable following. It was his unexpected arrest on the eve of the August protest, however, that thrust him into the limelight, sparking candle-lit marches across the country and swelling the ranks of his movement, Indian Against Corruption (IAC). Hazare was hailed as a leader of Gandhian proportions and applauded for his humble origins, numerous awards, and ecologically conscious development work in Ralegan Siddhi, where Hazare took up residence in 1975, following a brief career in the army. His movement, which appeared to be climbing from strength to strength, was thought to be a major political force of lasting influence. But in the year since the Ramlila protest, Hazare's movement has lost steam, with key leaders oscillating between calling for a stronger movement based on ‘the people's guidance’ and entertaining the possibility of entering electoral politics through the formation of a new political party. This article investigates the reasons for the deceleration of the Hazare movement, with an emphasis on why Hazare failed to win the support of the liberal and left sections of society, particularly the intelligentsia.     

Lattices,bargaining and group decisions

This essay aims at constructing an abstract mathematical system which, when interpreted, serves to portray group-choices among alternatives that need not be quantifiable. The system in question is a complete distributive lattice, on which a class of non-negative real-valued homomorphisms is defined. Reinforced with appropriate axioms, this class becomes a convex distributive lattice. If this lattice is equipped with a suitable measure, and if the mentioned class of homomorphisms is equipped with a metric, then the class and its convex sets are seen to possess certain characteristic properties. The main result (Theorem 6) follows from a combination of these results and a famous result due to Choquet.The mathematical scheme is then interpreted in the subject-language of choice among alternatives. It is shown, by means of an example, that the system furnishes all the ingredients for describing multi-group choices. Whether or not the same ingredients are also adequate for a behavioural theory of multi-group choices is an issue that will not be gone into. However, the example effectively illustrates how a process of bargaining can be described with the aid of the mathematical scheme.In the second example, a class of bargaining situations is modelled in the symbolism of linear programming with several objective functions combined with unknown weights; the cost vectors in such formulations are identified with homomorphisms, and the main theorem of this essay is applied.