Parent-Professional Power Relations: parent and professional perspectives

This paper reflects on a small-scale qualitative research study around the establishment of a conductive education centre in a city in the north of England. From the outset, the centre's existence presented a challenge to existing services because the monopoly control of existing professional practice and policy was under question. The research does not offer an evaluation of the effectiveness of conductive education. The task was to examine the centre's provision in relation to existing statutory services, and provide a forum for informed discussion relating to the provision and organisation of multi-professional services for disabled children. The paper suggests that, although there was a mutual tension between the centre and professionals, a number of pointers could become a starting point for a more equitable partnership between parents and existing service providers. We also argue, however, that such a notion of partnership is limited without the voices of disabled people.     

Nonparametric Estimation of the Probability of Detection of Flaws in an Industrial Component,from Destructive and Nondestructive Testing Data,Using Approximate Bayesian Computation

We consider the problem of estimating the probability of detection (POD) of flaws in an industrial steel component. Modeled as an increasing function of the flaw height, the POD characterizes the detection process; it is also involved in the estimation of the flaw size distribution, a key input parameter of physical models describing the behavior of the steel component when submitted to extreme thermodynamic loads. Such models are used to assess the resistance of highly reliable systems whose failures are seldom observed in practice. We develop a Bayesian method to estimate the flaw size distribution and the POD function, using flaw height measures from periodic in‐service inspections conducted with an ultrasonic detection device, together with measures from destructive lab experiments. Our approach, based on approximate Bayesian computation (ABC) techniques, is applied to a real data set and compared to maximum likelihood estimation (MLE) and a more classical approach based on Markov Chain Monte Carlo (MCMC) techniques. In particular, we show that the parametric model describing the POD as the cumulative distribution function (cdf) of a log‐normal distribution, though often used in this context, can be invalidated by the data at hand. We propose an alternative nonparametric model, which assumes no predefined shape, and extend the ABC framework to this setting. Experimental results demonstrate the ability of this method to provide a flexible estimation of the POD function and describe its uncertainty accurately.     

From the Inside Out: Environmental Agency Views about Communications with the Public

Relatively few studies have examined risk communication with the public from the viewpoint of the staff of institutions attempting such communications. This paper reports results of interviews with managers and staff of the New Jersey Department of Environmental Protection, on their programs' current and ideal communications with the public. Q analysis revealed two orthogonal perspectives on current program communications, the Enthused and the Constrained views. The primary focus of their divergence was on the matter of commitment and support for such communications. The Enthused group felt that they had attitudinal support from program culture and managers; the Constrained group focused on the lack of concrete operational support in terms of time, money, and expertise. These differences between the two groups did not appear to be associated with gender, managerial status, education, communication training, or organizational unit. When ideal program communications were discussed, the focus was on the need for all kinds of commitment and support (i.e., culture, managers, time, money, building expertise through training), as well as on more proactive and responsive communication. Both perspectives agreed that communication with the public is essential to their programs' success, trying new ways to communicate is worthwhile, scientific bases for decisions are not compromised by communication, and communication is not delegated to specialists. While varying ideas were held of the public's capacity and interest in communication, citizens were largely not held responsible for communication problems.     

Screening for prostate cancer by using random-effects models

Summary. Random-effects models are used to screen male participants in a long-term longitudinal study for prostate cancer. By using posterior probabilities, each male can be classified into one of four diagnostic states for prostate disease: normal, benign prostatic hyperplasia, local cancer and metastatic cancer. Repeated measurements of prostate-specific antigen, collected when there was no clinical evidence of prostate disease, are used in the classification process. An individual's screening data are considered one repeated measurement at a time as his data are collected longitudinally over time. Posterior probabilities are calculated on the basis of data from other individuals with confirmed diagnoses of each of the four diagnostic states.     

A Theory of Optimal Inheritance Taxation

This paper derives optimal inheritance tax formulas that capture the key equity‐efficiency trade‐off, are expressed in terms of estimable sufficient statistics, and are robust to the underlying structure of preferences. We consider dynamic stochastic models with general and heterogeneous bequest tastes and labor productivities. We limit ourselves to simple but realistic linear or two‐bracket tax structures to obtain tractable formulas. We show that long‐run optimal inheritance tax rates can always be expressed in terms of aggregate earnings and bequest elasticities with respect to tax rates, distributional parameters, and social preferences for redistribution. Those results carry over with tractable modifications to (a) the case with social discounting (instead of steady‐state welfare maximization), (b) the case with partly accidental bequests, (c) the standard Barro–Becker dynastic model. The optimal tax rate is positive and quantitatively large if the elasticity of bequests to the tax rate is low, bequest concentration is high, and society cares mostly about those receiving little inheritance. We propose a calibration using micro‐data for France and the United States. We find that, for realistic parameters, the optimal inheritance tax rate might be as large as 50%–60%—or even higher for top bequests, in line with historical experience.     

A Bayesian approach for misclassified ordinal response data

ABSTRACT

Motivated by a longitudinal oral health study, the Signal-Tandmobiel^® study, a Bayesian approach has been developed to model misclassified ordinal response data. Two regression models have been considered to incorporate misclassification in the categorical response. Specifically, probit and logit models have been developed. The computational difficulties have been avoided by using data augmentation. This idea is exploited to derive efficient Markov chain Monte Carlo methods. Although the method is proposed for ordered categories, it can also be implemented for unordered ones in a simple way. The model performance is shown through a simulation-based example and the analysis of the motivating study.     

Improving Risk Communication in Government: Research Priorities

Despite the increased interest in risk communication among government agencies, there is evidence that agencies'risk communication practices lag. We conducted a study to explore which risk communication research would be most important to improve government agencies'risk communication practices. Qualitative interviews and a survey of 145 risk communication experts based in academic institutions and government agencies explored how important research on each of 48 topics would be to improving agencies'risk communication efforts. Respondents identified topics within three areas as priorities for further research: 1) involving communities in agency decisionmaking; 2) communicating with communities of different races, ethnic backgrounds, and incomes; and 3) evaluating risk communication. Both practitioners and researchers responded to additional statements about agencies'risk communication practices with reservations about staff and managers'commitment to effective communication about environmental issues. We discuss the implications of these findings.     

The construction,composition and rationale of immigrants’ network: The support strategies of Ghanaian immigrants in Toronto,Canada

In this article, we investigate the construction, composition and rationale behind the personal networks of recent immigrants to Canada. Drawing on egocentric-network analysis and interviews with 172 Ghanaian immigrants in Toronto, we reveal their networking strategies during their integration. First, we identify social locations that help create ties with different groups: workplaces and schools offer access to ties with non-immigrants and other immigrants alike, while religious and ethnic organizations facilitate ties to co-nationals (i.e., Ghanaians). Second, most individuals within immigrants’ network are co-nationals whose relationship began in Canada, followed by sustained transnational ties in the origin and diaspora and few ties with the non-immigrant. The nature of this network is explained by examining the migration project of immigrants together with the context of reception in Canada, which suggests a desire by immigrants to stay in Canada and make Canada their second home. The implications of these findings are discussed.     

Tabulations for value at risk and expected shortfall

Value at risk and expected shortfall are the two most popular measures of financial risk. Here, we tabulate expressions for both these measures for over 100 parametric distributions, including all commonly known distributions, and illustrate a data application. We expect that this collection of expressions could serve as a source of reference and encourage further research with respect to measures of financial risk.