On a Class of Asymptotically Risk-Efficient Sequential Procedures

A class of sequential procedures is developed for the point estimation of the parameter(s) of a population under a family of loss functions plus cost function of the general form. Condition on the initial sample size is determined which ensures the asymptotic ‘risk-efficiency’ of the proposed class. By means of various examples, it is shown that many sequential point estimation problems can be handled with the help of the proposed class.     

Estimation procedures for a family of density functions representing various life-testing models

A family of density functions is considered which contains several life-testing models as specific cases. Uniformly minimum variance unbiased estimators are obtained for the positive and negative powers of the parameter, moments and reliability function. These general results provide the estimators for the specific models.     

Bayesian Estimation and Unit Root Test for Logistic Smooth Transition Autoregressive Process

The paper considers nonlinear logistic smooth transition autoregressive (LSTAR) process and aims to detect the unit root under the null hypothesis of a random walk process against the alternative of a stationary LSTAR process and to estimate the parameters of the process in Bayesian framework using MCMC. The simulation study is carried out for investigating the performance of the Bayes estimators for parameters and Bayesian unit root test and it has been observed that the estimates of parameters of the LSTAR process are close to the true parameter values. It has been observed that the Bayesian unit root test performs well and the power of the test is high even for the boundary cases having root close to unity, at least when the sample size is large. Since the LSTAR models are widely applied for real exchange rate modeling, the theoretical results are illustrated empirically for the real exchange rates of ten OCED countries.

     

Some properties of the distribution of an operational ridge estimator

Metrika - The present paper investigates the properties of the sampling distribution of an operational general ridge estimator. Exact expression are given for the moments and their approximations...     

Relational Co-ordination and Stigma at Work: How Frontline Employees Compensate for Failures in Public Health Systems

Co-ordinating collective work and communicating a shared understanding of tasks is necessary to accomplishing organizational goals. Stigma could exacerbate co-ordination challenges between public and private organizations by further widening differences in goals and incentives among employees. Using relational co-ordination theory, we explore how stigma can influence employee behaviour in the context of healthcare delivery. We study healthcare professionals and frontline workers involved in the fight against AIDS in India to examine how public health systems fail due to a lack of communication and co-ordination, and that these failures are worsened by stigma. When stigma is present, relationships between employees become strained due to misaligned work routines, lack of information sharing and cooperation failure. Our findings reveal emergent responses from frontline employees that mitigate co-ordination failures through: (1) role adaptation to improve predictability of tasks; (2) social purpose identification to promote a common understanding and engage stigmatized clients; and (3) affective attachment that encourages extra-role behaviours and task ownership. We draw implications for relational co-ordination and stigma, as well as public-private co-ordination in public health systems.     

Budget impact analysis of long acting injection for schizophrenia in Japan

Abstract

Aims: To estimate the budgetary impact of providing additional reimbursement for long acting injections for schizophrenia patients in psychiatric hospital settings in Japan to improve patient outcomes in schizophrenia.

Methods: Budget impact analysis of change in reimbursement policy using a prevalence-based model over a five-year time horizon. The results are reported as net change in expenditure and consequent cost/savings in Japanese yen at the time of analysis.

Results: The budget impact analysis shows that an increase in reimbursement for LAIs could lead to cumulative savings of an estimated 36.6 billion JPY over five years. These savings result from a decrease in hospitalization costs and an increased usage of LAI (assumed to be 10%). Based on the sensitivity analysis, the saving estimates are most sensitive to change in market share of generic and branded oral antipsychotics.

Limitations: Historical data were used to estimate the future costs of drug and hospitalization; however, it is not the best predictor of future, hence a source of potential bias. A good level of treatment adherence with oral antipsychotics was assumed, which is generally not the case; therefore, we might have overestimated the effectiveness of oral atypical antipsychotics. Additionally, the drug cost due to reimbursement might have also been overestimated because in clinical setting, the increase of LAI use may not have reached 10% of the market share. Lastly, patients’ behavior was derived from models, which may have loosely approximated the reality.

Conclusions: An additional reimbursement for the use of LAI in schizophrenia patients is likely to be cost neutral/cost saving and should be considered as a policy option to improve patient outcomes and budget sustainability.     

Policy, Markets and Knowledge: Strategic Synergies in Indian Pharmaceutical Firms

This paper addresses the question of how Indian pharmaceutical firms have transformed themselves from reverse-engineering firms focused on the domestic market to research-driven firms with global presence. It analyses the crucial and changing role of national, then international, innovation and regulatory policies and their impact on growth, performance and technology evolution of Indian pharmaceutical firms. The paper argues that although public policy increased market turbulence, it also provided new opportunities for firms to expand and build new technology, knowledge and market capabilities. From the 1950s Indian firms have pursued a variety of research, marketing and internationalization strategies to tackle changes prompted by policy, markets and knowledge complexities. The paper traces firm strategies that vary both in time and by firm, and argues that the successful firms have evolved substantively towards knowledge-based strategies. The paper then attempts to identify future directions for strategy, knowledge and markets.     

Robust linear static panel data models using ε-contamination

The paper develops a general Bayesian framework for robust linear static panel data models using$\epsilon$-contamination. A two-step approach is employed to derive the conditional type-II maximum likelihood (ML-II) posterior distribution of the coefficients and individual effects. The ML-II posterior means are weighted averages of the Bayes estimator under a base prior and the data-dependent empirical Bayes estimator. Two-stage and three stage hierarchy estimators are developed and their finite sample performance is investigated through a series of Monte Carlo experiments. These include standard random effects as well as Mundlak-type, Chamberlain-type and Hausman–Taylor-type models. The simulation results underscore the relatively good performance of the three-stage hierarchy estimator. Within a single theoretical framework, our Bayesian approach encompasses a variety of specifications while conventional methods require separate estimators for each case.     

Sequential estimation of a linear function of normal means under asymmetric loss function

The problem of estimating a linear function of k normal means with unknown variances is considered under an asymmetric loss function such that the associated risk is bounded from above by a known quantity. In the absence of a fixed sample size rule, sequential stopping rules satisfying a general set of assumptions are considered. Two estimators are proposed and second-order asymptotic expansions of their risk functions are derived. It is shown that the usual estimator, namely the linear function of the sample means, is asymptotically inadmissible, being dominated by a shrinkage-type estimator. An example illustrates the use of different multistage sampling schemes and provides asymptotic expansions of the risk functions. Received: August 1999     

Bayesian Analysis of Structural Changes in a Linear Regression Model: An Application to Rupee-Dollar Exchange Rate

Journal of Quantitative Economics - The objective of this paper is to find the points of structural shift in the exchange rate model under a Bayesian framework which incorporates the possibility of...