The Student-Supervisor Relationship in Social Work Education

Among the skills social workers claim for their professional practice, the understanding and use of a professional relationship is one of the most important. Most practitioners are familiar with the theoretical and practical issues of this subject, but for students they are among the most fundamental learning requirements of the social work course.     

Fisher's Information on the Correlation Coefficient in Bivariate Logistic Models

From a theoretical perspective, the paper considers the properties of the maximum likelihood estimator of the correlation coefficient, principally regarding precision, in various types of bivariate model which are popular in the applied literature. The models are: 'Full-Full', in which both variables are fully observed; 'Censored-Censored', in which both of the variables are censored at zero; and finally, 'Binary-Binary', in which both variables are observed only in sign. For analytical convenience, the underlying bivariate distribution which is assumed in each of these cases is the bivariate logistic. A central issue is the extent to which censoring reduces the level of Fisher's information pertaining to the correlation coefficient, and therefore reduces the precision with which this important parameter can be estimated.     

The Experimetrics of Public Goods: Inferring Motivations from Contributions

In public goods experiments, stochastic choice, censoring and motivational heterogeneity give scope for disagreement over the extent of unselfishness, and whether it is reciprocal or altruistic. We show that these problems can be addressed econometrically, by estimating a finite mixture model to isolate types, incorporating double censoring and a tremble term. Most subjects act selfishly, but a substantial proportion are reciprocal with altruism playing only a marginal role. Isolating reciprocators enables a test of Sugden’s model of voluntary contributions. We estimate that reciprocators display a self-serving bias relative to the model.      

Orphan Papers and Ghostwriting: The Case against the ICMJE Criterion of Authorship

Although popular, I argue that the International Committee of Medical Journal Editors (ICMJE) account of authorship is flawed. It inadvertently allows for practices that it was designed to prevent. In addition, it creates a new category of authorless papers—orphan papers. The original World Association of Medical Editors (WAME) criterion is preferable.     

A test of risk vulnerability in the wider population

Theory and Decision - Panel data from the German SOEP is used to test for risk vulnerability (RV) in the wider population. Two different survey responses are analysed: the response to the question...     

The within-household schooling decision: a study of children in rural Andhra Pradesh

Using microdata from a field survey of children in rural Andhra Pradesh, India, we estimate econometric models which aim to identify the key explanatory factors in the decision on schooling. The approach adopted is to focus on the effects of sibling competition within the household, by paying close attention to the number, age and gender of a child's siblings, while also taking account of the characteristics of the household and community. Our findings suggest that the schooling decision depends as much on the child's characteristics and position within the household, as on the circumstances in which the child lives.

The econometric modelling of social preferences

Experimental data on social preferences present a number of features that need to be incorporated in econometric modelling. We explore a variety of econometric modelling approaches to the analysis of such data. The approaches under consideration are: the Random Utility approach (in which it is assumed that each possible action yields a utility with a deterministic and a stochastic component, and that the individual selects the action yielding the highest utility); the Random Behavioural approach (which assumes that the individual computes the maximum of a deterministic utility function, and that computational error causes their observed behaviour to depart stochastically from this optimum); and the Random Preference approach (in which all variation in behaviour is attributed to stochastic variation in the parameters of the deterministic component of utility). These approaches are applied in various ways to an experiment on fairness conducted by Cappelen et al. (Am Econ Rev 97(3):818–827, 2007). Various models that we estimate succeed in capturing the key features of the dataset. Conclusions concerning fairness-related behaviour depend crucially on the choice of econometric model.     

GLOBAL LOG-CONCAVITY OF THE LIKELIHOOD IN MODELS WITH GROUPED DISCRETE DATA

The paper considers the property of global log-concavity of the likelihood function in discrete data models in which the data are observed in ‘grouped’ form, meaning that for some observations, while the actual value is unknown, the realisation of the discrete random variable is known to fall within a certain range of values. A typical likelihood contribution in this type of model is a sum of probabilities over a range of realisations. An important issue is whether the property of log-concavity in the ungrouped case carries over to the grouped counterpart; the paper finds, by way of a simple but relevant counter-example, that this is not always the case. However, in two cases of practical interest, namely the Poisson and geometric models, the property of log-concavity is preserved under grouping.