Finding Bayesian Optimal Designs for Nonlinear Models: A Semidefinite Programming‐Based Approach

This paper uses semidefinite programming (SDP) to construct Bayesian optimal design for nonlinear regression models. The setup here extends the formulation of the optimal designs problem as an SDP problem from linear to nonlinear models. Gaussian quadrature formulas (GQF) are used to compute the expectation in the Bayesian design criterion, such as D‐, A‐ or E‐optimality. As an illustrative example, we demonstrate the approach using the power‐logistic model and compare results in the literature. Additionally, we investigate how the optimal design is impacted by different discretising schemes for the design space, different amounts of uncertainty in the parameter values, different choices of GQF and different prior distributions for the vector of model parameters, including normal priors with and without correlated components. Further applications to find Bayesian D‐optimal designs with two regressors for a logistic model and a two‐variable generalised linear model with a gamma distributed response are discussed, and some limitations of our approach are noted.     

Information asymmetry,information dissemination and the effect of regulation FD on the cost of capital

This paper considers the impact of Regulation Fair Disclosure (FD) on firms’ information environments and costs of capital. For NYSE/Amex firms we find little evidence of a change in the cost of capital attributable to Regulation FD. For Nasdaq firms we find that Regulation FD increased firms’ costs of capital by 10–19 basis points per annum though the statistical significance of this change is modest for some of our models. We also show substantial cross-sectional variation in the cost of capital changes. We find that cost of capital changes were negatively related to both pre-regulation firm size and PIN. In addition to the findings regarding Regulation FD, this research contributes to a growing literature that documents links between firms’ information environments and their costs of capital.     

Local stakeholders,role and tourism development

Building sustainable communities, as well as sustainable forms of livelihood, including tourism, has been a key objective among many government agencies and community stakeholders. Against this background, and through the lens of role theory, the present study investigates the potential for sustainable tourism to be developed in a rural community. Data were gathered among business owners and residents of Bridgetown, Western Australia. Four key groups of participants emerged, each emphasizing participants' role as community, and therefore, as tourism stakeholders. Alignment with various perspectives of role theory, including functional, “symbolic interactionist”, structural and cognitive was noticed; similarly, consensus, conformity and role taking were identified as key concepts. Whether currently involved in tourism or not, participants' pro-active role suggesting practical ways to enhance the sustainability of local tourism could be a powerful tool in this and other communities seeking to build their destination image.     

Managing interdependencies in supplier networks

Building and managing a supplier base has been referred to in the literature as a key aspect of supplier management. Scholars have proposed a number of models aimed at enhancing the effectiveness of supplier network management, mainly based on a portfolio approach. In the IMP tradition of research, those models are often criticized as they ignore the interdependencies between the different existing dyadic relationships of a focal buyer company and its suppliers. Such interdependencies are the main focus of this paper, which has four objectives: (1) To analyze the types of relationships linking suppliers, (2) to understand the factors and dynamics underlying the creation and management of these relationships (3) to uncover existing links between buyer-supplier and supplier-supplier relationships, and (4) to clarify how different configurations of supplier relationship interactions impact on the performance of the actors involved. The paper discusses two empirical case studies, using the supplier networks of two focal buyer companies. We find that supplier interdependencies are mainly a by-product of the buyer-supplier dyads. Furthermore, the nature and dynamics of these dyads are a strong determinant of the scope and frequency of supplier connections and the corresponding effects on performance.     

Macroeconomic Policy Making,Exchange Rate Adjustment and Current Account Imbalances in Emerging Markets

Given a series of crisis events after 2007 the discussion about the adjustment channels of current account imbalances has been revived. We examine the role of exchange rates vs macroeconomic policies as determinants of current accounts for a set of 86 mainly emerging market economies between 1990 and 2013 to identify adjustment channels for global imbalances. We find that nominal exchange rates are not the main determinant of current account positions. Instead, depending on the region, monetary and/or fiscal policies are identified as the main driving force of current accounts. For East Asia and the oil exporting countries sterilization policies, i.e. relatively tight monetary policies, are the main determinants. In contrast for many European periphery countries fiscal policy stances are at the core of current account positions. Only for the Latin American countries does the exchange rate play a significant role as determinant of current account positions.     

The development of olive tourism in Western Australia: a case study of an emerging tourism industry

The recent development of olive growing in Western Australia, and its amalgamation with tourism and hospitality, provides opportunities for growers to showcase their products and for visitors to experience olive‐tasting and learn about an ancient food culture and rural activity ‘transplanted’ into the ‘New World’ from its ‘Old World’ roots. The present study examines the dimensions of this emerging niche market in Western Australia. Face‐to‐face and telephone interviews were conducted among 23 small olive‐growing operations located in this region to understand their scope for developing olive tourism. Overall, respondents' comments suggest that their involvement in olive tourism and hospitality could substantially provide benefits for visitors to rural areas and become a complementary alternative to other activities. To fulfil this potential, however, growers heavily rely on greater collaboration within their own industry, as well as on local authorities and tourism bodies in ways that include assistance, partnerships and promotion. Moreover, collaboration between olive growers and regional/tourism stakeholders, as well as government support may not only contribute to the sustainability of olive growing, but also to the emergence of olive tourism. In turn, these developments may also help develop a culinary identity and a tourism concept that may help minimise the threats of outside competition (cheaper olive imports) and rural decline. Copyright © 2010 John Wiley & Sons, Ltd.     

Access to Bottleneck Inputs under Oligopoly: A Prisoners' Dilemma?

We analyze the incentives of vertically integrated oligopolists to concede access to their bottleneck inputs to an entrant in the downstream market. First, two vertically integrated incumbents make access price offers to an entrant that chooses which one to accept, if any. Second, firms compete on Salop's circle. The firms may be asymmetrically located on the circle, to reflect differences in consumer shares. For some levels of asymmetry, the incumbents face a prisoners' dilemma with respect to conceding access to their bottleneck inputs. Entry by a downstream firm may lead to lower retail prices. However, entry may also lead to higher retail prices for the access provider and for the entrant. We also consider the cases where there are several incumbents and where the entrant makes the access price offers.     

Cellular phones in Mozambique: Who has them and who doesn't?

Cellular phones are considered one of the success stories of contemporary technology diffusion: there are three billion cellular telephones globally, and just over six billion people. This article describes the distributional boundary of the cellular telephone enterprise, as we see it in data from Mozambique. A telephone survey of mobile phone users there revealed that men outnumbered women, especially at higher levels of service and that most were urban, with a particular concentration in the capital city. Thus while pre-paid telephone plans have made basic cellular service affordable to many Mozambicans, the lack of rural infrastructure stills puts access out of the reach of a majority. In addition, pre-paid users pay more per minute for their service—probably not a fair situation for the poor families that tend to take this route to telecommunications.