Bayesian regression analysis using poly-t densities

Poly-t densities are defined by the property that their kernel is a product, or ratio of products, of Student-t kernels. These multivariate densities arise as Bayesian posterior densities for regression coefficients, under a surprising variety of specifications for the prior density and the data generating process. Although no analytical expression exists for the integrating constant and moments of these densities, these parameters are obtained through numerical integration in a number of dimensions given by the number of Student-t kernels in the numerator, minus one. The paper reviews how poly-t densities arise in regression analysis, and summarizes the results obtained for a number of models.     

Optimal search auctions

We study the design of profit maximizing single unit auctions under the assumption that the seller needs to incur costs to contact prospective bidders and inform them about the auction. With independent bidders’ types and possibly interdependent valuations, the seller's problem can be reduced to a search problem in which the surplus is measured in terms of virtual utilities minus search costs. Compared to the socially efficient mechanism, the optimal mechanism features fewer participants, longer search conditional on the same set of participants, and inefficient sequence of entry.     

Somatic distance,trust and trade

Somatic distance, or differences in physical appearance, proves to be extremely important in the gravity model of bilateral trade in conformity with results in other areas of economics and outside in the social sciences. This is also true independently of survey evidence about bilateral trust. These findings are obtained in a sample of the 15 members of the European Economic Area in 1996. Robustness tests also show that somatic distance, as well as co‐ancestry, has a more reliable influence on bilateral trade than the other customary cultural variables. The article finally discusses the interpretation and breadth of application of these results.     

Information sharing as a safeguard against the opportunistic behavior of South African Karoo Lamb farmers

Misconduct in global meat supply chains are omnipresent and even more so in differentiated chains where credence attributes such as origin and taste are used to differentiate the product. By definition, these attributes signal asymmetric information which implies that in the presence of bounded rational individuals with conflicting interests, misconduct in the form of opportunistic behavior is bound to prevail. Increased information exchange through farmer networks is, however, expected to reduce opportunistic behavior. In the case of a differentiated meat product, such as Karoo Lamb, the article studies the farmer‐abattoir transaction with the purpose of recommending strategies that can be implemented to reduce the farmer's tendency to behave opportunistically. The article employs the PLS approach to SEM and reveals a significant negative relationship between information shared and opportunistic behavior. The results indicate significant positive relationships between trust in the abattoir and information shared as well as between farmer networks and information shared. These results are indicative of the support provided to the information shared construct by higher levels of trust between farmers and abattoirs and established farmer networks. It is, therefore, recommended that differentiated meat supply chains, through their various associations, concentrate their efforts to promote information sharing by building stronger, trust centered relationships and by supporting farmer networks.     

Optimal Patent Protection in a Two-Sector Economy

This article addresses the issue of optimal patent protection in an economy with a downstream and an upstream sector. The key insight is that higher patent protection in the downstream sector raises the incentives of agents to do R&D in that sector but discourages innovation in the upstream sector because of a market size effect. Hence, higher patent protection in the upstream sector accelerates growth whereas higher patent protection in the downstream sector slows it down. If some innovation is socially desirable, optimal patent protection is necessarily higher in the upstream than in the downstream sector.     

The Last Word on the Wage Curve?

Abstract.  Since 1990, there has been extensive international research on the responsiveness of wages of individuals to changing local labour market conditions. For many countries, an inverse relationship between wages and local unemployment rates has been found. In their book, The Wage Curve , Blanchflower and Oswald argued that the unemployment elasticity of pay is around −0.1 in most countries. In a 1995 literature survey, Card referred to this striking empirical regularity as being close to an 'empirical law of economics'. Nonetheless, reported elasticities do vary, even excluding outliers, between about −0.5 and +0.1. There is also considerable heterogeneity among wage curve studies in terms of data and model specification. This paper carries out meta‐analytic techniques on a sample of 208 elasticities derived from the literature to uncover the reasons for the differences in empirical results across studies. Several causes of variation are identified. There is also clear evidence of downward publication bias. In addition, many reported t ‐statistics are biased upwards due to the use of aggregate unemployment rates. A maximum likelihood method and a trimming procedure are used to correct for these biases. Both methods give similar results for our sample. An unbiased estimate of the wage curve elasticity at the means of study characteristics is about −0.07.     

PRIMITIVE ACCUMULATION,GROWTH AND THE GENESIS OF SOCIAL CLASSES

The aim of this paper is to show that inequalities of wealth can be necessary conditions to explain the apparition and rise of a capitalistic system. We try to highlight Marx's insights on primitive accumulation. Our dynamic framework is consistent with Roemer's idea of endogenous class stratification. We extend this calculation by incorporating some features of the Pasinetti–Samuelson–Modigliani model, and provide an example of possible microfoundations.     

International Trade Agreements and International Migration

Despite large potential economic gains, bilateral and multilateral negotiations focusing on liberalisation of migration have not shared the high profile of international trade negotiations and agreements. Migration and trade have been traditionally viewed rather separately and the relevance of the many, and complex, interdependencies has been given remarkably little attention in the literature to date. In this article, we focus on the two‐way interaction between international migration and agreements designed to enhance cross‐border trade and investment. Liberalisation of international trade in services and in the movement of people potentially offers much greater economic gains than liberalisation of remaining barriers to goods trade. However, progress within multilateral frameworks is fraught with difficulty. The World Trade Organization’s General Agreement on Trade in Services (GATS) has yielded little real progress so far and negotiations within more flexible unilateral and bilateral frameworks are likely to be more successful in liberalising the movement of labour. We discuss a range of specific examples, focusing particularly on the interesting case of New Zealand. We find that trade agreements are increasingly including agreements on migration, though typically favouring temporary migration and involving numerically modest quotas. We conclude that migration regulatory frameworks are likely to be further and more strongly linked to trade and investment agreements in the future, particularly given changing economic and demographic forces. The primary focus of migration policies may nonetheless remain different from that of trade policies. While further migration liberalisation is likely to be through bilateral and regional agreements, it will be important to try to lock in the gains of such agreements, while simultaneously working to consolidating these in a way that will help to facilitate future multilateral agreement.