Bayesian semiparametric modeling and inference with mixtures of?symmetric distributions

We propose a semiparametric modeling approach for mixtures of symmetric distributions. The mixture model is built from a common symmetric density with different components arising through different location parameters. This structure ensures identifiability for mixture components, which is a key feature of the model as it allows applications to settings where primary interest is inference for the subpopulations comprising the mixture. We focus on the two-component mixture setting and develop a Bayesian model using parametric priors for the location parameters and for the mixture proportion, and a nonparametric prior probability model, based on Dirichlet process mixtures, for the random symmetric density. We present an approach to inference using Markov chain Monte Carlo posterior simulation. The performance of the model is studied with a simulation experiment and through analysis of a rainfall precipitation data set as well as with data on eruptions of the Old Faithful geyser.     

Liberal Education and Social Welfare

The author presents the vulnerability, risk, and resilience model as a mechanism for improved content integration in the Human Behavior and the Social Environment sequence in social work education. The model demonstrates the interaction of community and social context variables with individual characteristics in the development of social work problems. The five steps in the model are (1) define the social work problem of concern, (2) identify risk and protective factors in the social context, (3) identify intrinsic vulnerability and invulnerability characteristics, (4) intersect these two, and (5) explore intervention: and prevention options. In addition, she provides a rationale and background for the model, describes the model itself, and develops an example from social work practice (adolescent substance abuse) for social work education.     

Interrogating Mixed-Race: A Crisis of Ambiguity?

In many respects, issues surrounding ‘mixed-race’ identities rupture and dislocate much current thinking within post-race and new ethnicities paradigms. This article seeks to critically engage with what is arguably a marginalized and diverse ‘community’. An evaluation of theories emanating from the UK and USA seeks to challenge hybrid degenerative theories, and more recent attempts at explaining how such identities are negotiated in complex social arenas. What emerges is that some theories are underpinned by static and linear behavioural patterns, which appear oversimplified. Key questions are raised in order to further explore whether ‘mixed-race’ identities are genuinely marginalized and remain ambiguous in a range of physical, social, emotional and ideological contexts. Reflecting upon such issues seeks to prompt questions as to whether there can be a more sophisticated and sensitive understanding of the unique experiences (both positive and negative) of ‘mixed-race’ individuals. By doing so, it is hoped that such a topic becomes more central to considerations of how prejudice and discrimination operate across and within a wide variety of settings.     

Understanding innovation performance and its antecedents: A socio-cognitive model

Little attention in the previous literature has been paid to understanding employees’ factors that drive customer development knowledge and performance from the perspective of social psychology. Drawing on social cognitive theory, this study validates a research model that examines the above issue. In the setting of new product development across high-tech firms in Taiwan, this study postulates that innovation self-efficacy, role conflict, and role ambiguity influence innovation performance directly and indirectly via the mediation of customer knowledge development and innovation outcome expectation. This study contributes to the social science literature by applying social cognitive theory to the rarely explored area of innovation performance and by presenting an operationalization of role stressors (i.e., role ambiguity and role conflict) in the area. Lastly, managerial implications and limitations from the empirical findings are provided.     

The Role of Revenue‐Focused Managerial Performance Measures in Supply Chain Coordination

Many firms employ revenue‐focused managerial performance measures (RF‐MPMs) that cause managers to worry more about revenues than about costs. Although this can seemingly misalign the interests of a manager, we show that the use of such measures can help supply chain partners to overcome hold‐up issues with respect to capacity and promotion investments. We develop a game theoretic model in which two supply chain partners engage in repeated interactions in which the supplier invests in capacity and the buyer invests in demand promotion. Following the realization of demand in each period, the two firms negotiate over the output quantity and wholesale price. The novelty of our model is that we allow the owners of each firm to delegate decision‐making power and negotiating responsibility to a free‐agent manager. We characterize the conditions under which the owners of both firms employ RF‐MPMs in equilibrium and benefit from doing so. For a special case of our model, we show that for the owners of the buyer, an RF‐MPM is equivalent to a price only relational contract, and that it complements a price and quantity relational contract as a mechanism for mitigating hold‐up issues.