Statistical Decision Problems and Bayesian Nonparametric Methods

This paper considers parametric statistical decision problems conducted within a Bayesian nonparametric context. Our work was motivated by the realisation that typical parametric model selection procedures are essentially incoherent. We argue that one solution to this problem is to use a flexible enough model in the first place, a model that will not be checked no matter what data arrive. Ideally, one would use a nonparametric model to describe all the uncertainty about the density function generating the data. However, parametric models are the preferred choice for many statisticians, despite the incoherence involved in model checking, incoherence that is quite often ignored for pragmatic reasons. In this paper we show how coherent parametric inference can be carried out via decision theory and Bayesian nonparametrics. None of the ingredients discussed here are new, but our main point only becomes evident when one sees all priors—even parametric ones—as measures on sets of densities as opposed to measures on finite-dimensional parameter spaces.     

Bridging Business and Society: The Abrinq Foundation in Brazil

This article presents the process of creation and expansion of the Fundação Abrinq pelos Direitos da Criança et do Adolescente (Abrinq Foundation for Rights of Children and Adolescents). Established in 1990 by a group of entrepreneurs from the Brazilian Toy Manufacturers’ Association (ABRINQ), the Fundação Abrinq has been successful at raising the issue of children in Brazilian society by bridging business and several other sectors of society. This article more particularly examines (1) the societal challenges related to the situation of children in Brazil; (2) the creation and development of the Abrinq Foundation; and (3) the achievements of this innovative bridging organization over 15 years.     

Raising the bar (6)

Raising the bar (6). Spatial Economic Analysis. This editorial summarizes and comments on the papers published in issue 12(4) so as to raise the bar in applied spatial economic research and highlight new trends. The first paper addresses the question of whether ‘jobs follow people’ or ‘people follow jobs’. The second paper develops a new methodology to determine functional regions. The third paper is a major contribution to the growing literature on new modelling approaches and applications of disaster impact models. The fourth paper focuses on the costs and benefits of higher education. The fifth paper develops a two-step procedure to identify endogenously spatial regimes in the first step using geographically weighted regression, and to account for spatial dependence in the second step. Finally, the sixth paper estimates a dynamic spatial panel data model to explain house prices and to show that restricted housing supply in the city of Cambridge, UK, has some undesirable labour market effects.     

Exploring sources and outcomes of trust and commitment to nonprofit organizations: The case of Amnesty International Portugal

The interactions between customers and organizations have been regarded as a core aspect in cocreating and developing new products and practices. The current study explores these interactions in the context of citizens and nonprofit organizations. The study comprises two parts: (a) a qualitative approach using interviews and the analysis of social networks to better understand the organization's social media marketing practices and corresponding outcomes and (b) a quantitative approach to analyze antecedents and outcomes of trust and being committed to participate in a nonprofit organization such as Amnesty International. From the qualitative approach, the findings highlight that Amnesty International uses social media (Facebook) to share information, and citizens tend to consider sharing posts, but they do not express new ideas or interact with the organization. These findings contribute to structure the model analyzed in the second stage of the research. Regarding the qualitative approach, the results show that organizational credibility is the most significant driver of trust followed by communicative ability. Affectively commitment to participation and relationship perception act as outcomes of overall commitment.     

Quantile serial dependence in crude oil markets: evidence from improved quantilogram analysis with quantile wild bootstrapping

We examine the quantile serial dependence in crude oil prices based on the Linton and Whang’s quantile-based portmanteau test which we improved by means of quantile wild bootstrapping (QWB). Through Monte Carlo simulation, we find that the quantile wild bootstrap-based portmanteau test performs better than the bound testing procedure suggested by Linton and Whang. We apply the improved test to examine the efficiency of two crude oil markets – WTI and Brent. We also examine if the dependence is stable via rolling sample tests. Our results show that both WTI and Brent are serially dependent in all, except the median quantiles. These findings suggest that it may be misleading to examine the efficiency of crude oil markets in terms of mean (or median) returns only. These crude oil markets are relatively more serially dependent in non-median ranges.     

Project Management of Production Line Automation: A Comparative Analysis of Project Management in Brazil and Colombia

This article aims to evaluate the production line automation projects developed by Brazilian and Colombian companies from the Project Management perspective, through the analysis of the application degree of PMBOK processes, to understand how formal techniques are being employed in these countries and also to identify improvement opportunities, when necessary. Data were collected through a survey. The similarity index between the ten processes, with the highest application degree in the Brazilian and Colombian samples, was 70%. For the processes with the lowest application degree, the similarity index was 60%. No similar study was found in the literature.     

Do Sovereign Defaults Hurt Exporters?

This paper uses a difference-in-difference methodology similar to the one originally proposed by Rajan and Zingales to test whether sovereign defaults hurt the more export-oriented industries disproportionately, and it finds strong support for this hypothesis. However, contrary to the findings of previous studies, our estimates suggest that the effect of defaults is short-lived.     

Valuing the implicit guarantee of the Federal National Mortgage Association

The paper analyzes the guarantee of the Federal National Mortgage Association (FNMA). Rather than try to price the guarantee, we used time-series estimates of its value from Kane and Foster to infer the behavior of FNMA in exploiting the guarantee. The results are consistent with a model that predicts that FNMA does not take as much risk as it might. Rather, it trades off risk and return, but it does increase risk and exploit the guarantee when it gets in trouble (as it did in 1981).We have received helpful research assistance from Peter Carr and Bruno Gerard.