On the performance of tests by Wu and by Hausman for detecting the ordinary least squares bias problem

We first consider the performance of the Wu (1973) - Hausman (1978) (W-H) specification error test as a test for the existence of ordinary least squares (OLS) bias. We discuss power properties of the test under alternative null hypotheses, one of which has not previously been considered. We next consider how the W-H test performs as an indicator of the extent (rather than the existence) of an OLS bias problem, since this usage of the test seems common in applied studies. Finally Monte Carlo methods are used to evaluate Wu's two-step estimation procedure involving the W-H test as a pretest.     

Knowledge Networks and Careers: Academic Scientists in Industry–University Links*

abstract Careers are central to our understanding of the knowledge creation dynamics of network organizations. Based on the example of R&D project collaboration between firms and universities, this paper examines the emerging forms of career models that support knowledge flows between organizations. It explores how some large firms in the high‐technology sectors have sought to break away from the limitations of internal R&D and firm‐based careers for scientists by engaging in external collaborative projects to gain access to the open knowledge networks of university researchers. It examines how the firms seek to forge close institutional ties with their university partners and develop network career structures in order to engage academic scientists in joint knowledge production. It argues that firms have sought to extend their human resource and knowledge boundaries into the established internal labour markets of the universities with which they collaborate, leading to the formation of a pool of joint human resources with work experiences and career patterns straddling the two sectors. The paper develops the concept of an ‘overlapping internal labour market’ to provide a conceptual bridge between internal labour markets and network organizations.     

Hysteresis and sluggishness in Portuguese unemployment, 1977–88

The phenomenon of unemployment persistence led to the development of alternative theories of unemployment. Among these the ‘hysteresis’ concept by Blanchard and Summers (1987) received a wide interest. Based on this notion we developed a generalized model that nests Blanchards and Summers' theory. Using this framework we conducted an empirical investigation for the Portuguese labour market (1977–88). The results obtained point towards the existence of labour demand sluggishness, wage inertia and unemployment hysteresis. The model also suggests the existence of a rather inelastic labour demand curve.     

总编圈点

一个国家名牌出口商品的多少,反映这个国家综合实力的大小,经济竞争力的强弱,以及科学技术发展水平的高低。美国、日本、欧洲一些国家之所以商品出口强势历久不衰,就是由于它们在科学技术的有力支持下,长期以来培育出一大批叫得响、过得硬、受消费者欢迎的名牌商品,并且缘于这些商品而造就出众多赫赫有名、腰缠万贯的大公司、大企业。我国是个发展中国家,虽然改革开放20多年来经济大踏步前进,有了飞跃发展,但与西方经济强国相比,还有相当大的差距。然而,凡事预则立,不预则废。尤其我国入世后,要按照世贸组织的游戏规则开展对外经贸活动,与贸易伙伴     

American options and callable bonds under stochastic interest rates and endogenous bankruptcy

A new characterization of the American-style option is proposed under a very general multifactor Markovian and diffusion framework. The efficiency of the proposed pricing solutions is shown to depend only on the use of a viable valuation method for the corresponding European-style option and for the transition density of the model’s state variables. Under a Gauss-Markov stochastic interest rates setup, these new American option pricing solutions are shown to offer a much better accuracy-efficiency trade-off than the approximations already available in the literature. This result is also used to price callable corporate bonds under an endogenous bankruptcy structural approach, by decomposing the option to call or default into a European put on the firm value plus two early exercise premium components.     

The Size of Terroir: A Theoretical Note on Economics and Politics of Geographical Indications

Geographical indications (GI) certify the geographical origins of a product and delineate the specific area in which the certified product must be produced. Despite a large literature on the economics of GIs, few papers have explored the question of the optimal size of GI regions. This note presents a flexible conceptual framework to explore the economics and politics of the delimitation of a GI. The general framework describes the efficiency and distributional effects of the size of a GI and shows how this affects interest groups’ incentives to influence government decision‐making.     

The Impact of a Conditional Cash Transfer Programme on Consumption in Colombia*

This paper studies the impact of a conditional cash transfer programme in Colombia on the total consumption of very poor households and on its components. Our evaluation methodology involves comparing household expenditures in areas in which the programme was not implemented (control) and those in which it was (treated). We use a quasi‐experimental approach, as the Familias en Acción programme was not randomly assigned across localities, for political reasons. We condition on a large range of household‐ and municipality‐level characteristics, and also control for pre‐programme differences in the outcomes of interest using a differences‐indifferences methodology. We find that the programme has been effective at greatly increasing total consumption and its main component, food consumption, in both rural and urban areas. The programme has also contributed to improvements in the quality of food consumed, in particular of items rich in proteins (milk, meat and eggs) and of cereals. Furthermore, the programme has created redistributive effects in favour of children through expenditure on education and children's clothing, while it has not significantly affected consumption of adult goods such as alcohol and tobacco or adults’clothing.     

Taxation Policies Adjust,Motor Vehicles Boost

In recent years,Chinese automotive industry,as one of the pillar industries has kept on rising.In 2006,Chinese auto production ranked the third in the world. The governmental authorities are also studying the corresponding taxations to boost the healthy development of Chinese automotive industry. Mr.Shi Yaobin,Chief-Director of Taxation Department, the Ministry of Finance of ER.C,gave a lecture on current taxation items in China's auto industry and released infor-     

An Empirical Re-Examination of the Cross-Section of Expected Returns: UK Evidence

This paper is a study of the Fama and French (1992) analysis in the UK context. Consistent with their findings, our results do not support a positive relationship between beta and average monthly returns. We find that book-to-market equity and market leverage are consistently significant in explaining UK average returns. Contrary to the Fama-French evidence, size has an insignificant effect on average returns. A puzzling negative beta-returns relationship is found in some monthly regressions,and results based on annual data reveal a reversal of betas for the smallest-size portfolios. Some possible explanations are offered for these findings.     

Concessionary lending to developing countries

International transfers to promote the development of countries in the Third World began at the end of the Second World War. At first they were in the form of grants, mostly to colonies or ex-colonies. Then official development assistance from most industrial countries to most developing countries was institutionalized as it became apparent that the international capital market was inadequate in size and too costly for very poor countries. This led to official international lending on increasingly ‘soft’ terms. The ‘softening’ was brought about in a long complex discussion among the lending governments mostly within the Development Assistance Committee of the Organisation for Economic Cooperation and Development Theoretical and practical considerations brought the argument substantially to an end in the late 1970s with the widespread acceptance of the principle that, after all, grants were preferable for the poorest of developing countries.