Normative evaluation of tax policies: from households to individuals

We simulate a hypothetical family tax credit on a sample of French couples, using jointly a collective model of labor supply and a tax-benefit calculator. Work behaviors represent here a general concept of “effort,” and hence, individual productivities cannot be assimilated with wage rates. They are retrieved by inversion of the optimal household program under simple assumptions on household preferences and bargaining rules. The calibrated model is used to predict incentive effects of the reform and distributive impacts on individuals and households. The desirability of the reform depends on which of these two welfare units is used for normative evaluation.      

Relative effect sizes for measures of risk

Effect sizes are an important component of experimental design, data analysis, and interpretation of statistical results. In some situations, an effect size of clinical or practical importance may be unknown to the researcher. In other situations, the researcher may be interested in comparing observed effect sizes to known standards to quantify clinical importance. In these cases, the notion of relative effect sizes (small, medium, large) can be useful as benchmarks. Although there is generally an extensive literature on relative effect sizes for continuous data, little of this research has focused on relative effect sizes for measures of risk that are common in epidemiological or biomedical studies. The aim of this paper, therefore, is to extend existing relative effect sizes to the relative risk, odds ratio, hazard ratio, rate ratio, and Mantel–Haenszel odds ratio for related samples. In most scenarios with equal group allocation, effect sizes of 1.22, 1.86, and 3.00 can be taken as small, medium, and large, respectively. The odds ratio for a non rare event is a notable exception and modified relative effect sizes are 1.32, 2.38, and 4.70 in that situation.     

Occupational therapy students' contribution towards enabling potential in a semi-rural community

Occupational therapy students at the University of Pretoria engage in a 7-week service learning fieldwork in their fourth year. This fieldwork takes place in a semi-rural community. The article reports on a successful project where the students enabled adult learners with disabilities to improve their engagement in meaningful activities and trained the learners in selected prevocational skills. The students included a teacher from the center and she was given the opportunity to expand her skills in teaching as well. The ZOPP model of community project planning was used and proved to be a useful tool for students who have limited time for planning, implementation and evaluation of a project.     

Individual vs. couple behavior: an experimental investigation of risk preferences

In this article, we elicit both individuals’ and couples’ preferences assuming prospect theory (PT) as a general theoretical framework for decision under risk. Our experimental method, based on certainty equivalents, allows to infer measurements of utility and probability weighting at the individual level and at the couple level. Our main results are twofold. First, risk attitude for couples is compatible with PT and incorporates deviations from expected utility similar to those found in individual decision making. Second, couples’ attitudes towards risk are found to be consistent with a mix of individual attitudes, women being more influent on couples’ preferences at low probability levels.     

Enhancing Confidentiality within Small Groups: The Experiences of AIDS Service Organizations

Fear that others will not maintain confidentiality can prevent persons living with HIV/AIDS (PHAs) from participating in small groups. This article reports on practices for enhancing confidentiality among group members. The research involved surveying group workers on practices used to promote confidentiality and providing PHAs opportunity to share their perspectives. Group workers most frequently reported discussing confidentiality with group members, modelling respect of confidentiality, and seeking member agreement to maintain confidentiality. They also shared suggestions and described challenges related to maintaining confidentiality. Overall, the PHAs agreed with the reported practices. However, differences did emerge around the use and emphasis of certain means, such as the use of signed agreements.     

The structure and evolution of the strategic management field: A content analysis of 26 years of strategic management research

This paper analyses 26 years of strategic management research published in Academy of Management Journal, Academy of Management Review, Administrative Science Quarterly and Strategic Management Journal. Through a content analysis, it studies the relationships between the subfields of strategic management. A multiple correspondence analysis provides a map of keywords and authors, and a framework to track this literature over the 26‐year period. A discussion of future pathways in the strategic management literature is also provided.     

Discounting health and money: New evidence using a more robust method

This study compares discounting for money and health in a field study. We applied the direct method, which measures discounting independent of utility, in a representative French sample, interviewed at home by professional interviewers. We found more discounting for money than for health. The median discount rates (6.5% for money and 2.2% for health) were close to market interest rates, suggesting that at the aggregate level the direct method solves the puzzle of unrealistically high discount rates typically observed in applied economics. Constant discounting fitted the data better than the hyperbolic discounting models that we considered. The substantial individual heterogeneity in discounting was correlated with age and occupation.     

Likelihood-based estimation for Gaussian MRFs

Markov random fields (MRFs) express spatial dependence through conditional distributions, although their stochastic behavior is defined by their joint distribution. These joint distributions are typically difficult to obtain in closed form, the problem being a normalizing constant that is a function of unknown parameters. The Gaussian MRF (or conditional autoregressive model) is one case where the normalizing constant is available in closed form; however, when sample sizes are moderate to large (thousands to tens of thousands), and beyond, its computation can be problematic. Because the conditional autoregressive (CAR) model is often used for spatial-data modeling, we develop likelihood-inference methodology for this model in situations where the sample size is too large for its normalizing constant to be computed directly. In particular, we use simulation methodology to obtain maximum likelihood estimators of mean, variance, and spatial-depencence parameters (including their asymptotic variances and covariances) of CAR models.     

The alert-delay competing risks model for maintenance analysis

The paper considers the modelling of the dependency between corrective maintenance and condition-based preventive maintenance of complex repairable systems. A new model of dependent competing risks is proposed, called the alert-delay (AD) model. This model has different properties from that of the delay-time, repair-alert and proportional warning constant inspection models and happens to fit some data sets which could not be fitted by the previous models. The main features of the AD model are derived: probabilistic properties and statistical analysis. Simulation results and an application to real data are presented.     

Estimation in a Two Variance Components Model When one Component is Known

We study a mixed linear model with two variance components. We suppose that one component is known. The objective of the paper is the estimation of the unknown component. The usual MINQE estimators seem to be unadapted to the problem. So we propose a new family of quadratic estimators, based on a natural class of estimators and the idea upon which the MINQE theory is built. All the estimators are compared on simulated data.