Optimal immigration, education and growth in the long run

The paper extends Manning's model on education and balanced growth to include labour immigration. Each immigration unit is assumed to consist of one skilled worker and some unskilled members. The optimal immigration policy which maximizes the per capita steady-state consumption of the host country is derived. We show that optimal immigration policy can reduce the steady-state skilled labour ratio. More interesting still, contrary to the widespread belief that immigration of skilled workers hurts local skilled workers, it is the unskilled local workers whose interests are threatened by optimal immigration policy.     

Hypothesis testing based on goodness-of-fit in the moving average time series model

Small sample properties of t-tests are compared with those of tests based on relative goodness- of-fit in the context of the first order moving average time series model. Monte Carlo experiments reported in the paper suggest that the actual size of these t-tests greatly exceeds theoretical large sample significance levels, while conformity of goodness-of-fit statistics to the appropriate chi-square or F-distributions is much closer. The evidence presented suggests that practitioners are well advised to employ goodness-of-fit tests as a check on results of t-tests particularly when the latter indicate ‘significance’.     

Coase theorem,liability rules and social optimum

Zusammenfassung Das Coase-Theorem, Haftungsregeln und das soziale Optimum. — In diesem Beitrag haben wir gezeigt, da\ es zwei Wege gibt, das Coase-Theorem darzustellen; erstens unter Verwendung von Eigentumsrechten und zweitens unter Verwendung von Haftungsregeln. Wir haben bewiesen, da\ das Coase-Theorem richtig ist, wenn es in der Form von Eigentumsrechten und symmetrischen Haftungsregeln dargestellt wird. Es wird gezeigt, da\ sowohl der Beweis von Gilford und Stone als auch die Widerlegung von Marchand und Rüssel falsch sind. Allerdings k?nnen beide Aufs?tze als Analysen der Wirkungen von Haftungsregeln auf die Ressourcenallokation ohne Handel angesehen werden und als Vorschl?ge für m?gliche Haftungsregeln, die von den Regierungen erlassen werden k?nnen, um die externen Effekte zu korrigieren. Wenn allerdings die von der Regierung erlassene Haftungsregelung asymmetrisch ist, dann h?ngt die Ressourcenallokation von der Art dieser Regelung ab. Wird das soziale Optimum lediglich im Hinblick auf die Technologie definiert, dann sind der Handel zwischen den Beteiligten und die Pigouschen Steuern sich gegenseitig ausschlie\ende Verfahren, um das soziale Optimum zu erreichen. Findet kein Handel statt, dann ist die einseitige Pigou-Steuer ausreichend, um das soziale Optimum zu erreichen. Wird andererseits das soziale Optimum sowohl vom Standpunkt der Technologie als auch in rechtlicher Hinsicht definiert, dann führt die einseitige Pigou-Steuer nicht zu einer sozial optimalen Ressourcenallokation.

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Résumé Le théorème de Coase, les règles d’obligation et l’optimum social. — Dans cet article nous avons démontré qu’il y a deux méthodes différentes de déterminer le théorème de Coase. Une méthode est à la manière des droits de propriété et l’autre à la manière des règles d’obligation. Nous avons prouvé que le théorème de Coase est correct s’il est déterminé à la manière des droits de propriété et des règles d’obligation symétriques. Nous démontrons que la preuve présentée par Gilford et Stone est incorrecte aussi bien que la dispreuve du théorème de Coase présentée par Marchand et Russel. Cependant, on peut regarder les deux papiers comme des analyses des effets des règles d’obligation sur l’allocation de ressource en l’absence de commerce et comme des propositions des règles d’obligation possibles que le gouvernement devrait imposer pour corriger l’externalité. Cependant, si la règle d’obligation imposée par les gouvernements soit asymétrique l’allocation de ressource dépend des règles d’obligation imposées. Si l’optimum social soit défini seulement à la manière de la technologie le commerce entre les parties touchées et une taxe Pigovienne sont des moyens mutuellement exclusifs pour arriver au optimum social. En l’absence du commerce la taxe unilatérale Pigovienne est suffisante pour arriver au optimum social. D’autre part, si l’optimum social soit défini à la manière de la technologie aussi bien que de l’institution legale, une taxe unilatérale Pigovienne ne conduira pas à l’allocation de ressource d’optimum social.

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Resumen El teorema de Coase, reglas de endeudamiento y óptimo social. — En este artículo hemos mostrado que hay dos caminos diferentes para plantear el teorema de Coase. Uno en términos de los derechos de propiedad y el otro en términos de las reglas de endeudamiento. Hemos mostrado que el teorema de Coase es correcto cuando es planteado en términos de los derechos de propiedad y reglas de endeudamiento simétricas. Se muestra que la prueba presentada por Gilford y Stone es incorrecta, como también la desaprobación del teorema de Coase presentada por Marchand y Russel. Sin embargo, ambos artículos pueden ser tratados como analisis de los efectos de reglas de endeudamiento sobre la asignación de recursos en ausencia de comercio y como sugerencias de posibles reglas de endeudamiento a ser propuestas por los gobiernos para corregir la externalidad. Pero, cuando la regla de endeudamiento impuesta por los gobiernos es asimétrica, la asignación de recursos depende de las reglas de endeudamiento impuestas. Si el óptimo social es definido solamente en términos de tecnología, el comercio entre las partes comprometidas y el impuesto de Pigou son dispositivos mutuamente excluyentes para alcanzar el óptimo social. En ausencia de comercio, el impuesto unilateral de Pigou es suficiente para alcanzar el óptimo social. Por el otro lado, si el óptimo social es definido tanto en términos de la tecnología como de la institución legal, el impuesto unilateral de Pigou no llevará a una asignación social de recursos óptima.

     

Increasing the usability and accessibility of geodynamic modelling tools to the geoscience community: UnderworldGUI

Geoscientists are faced with a number of complexities that represent obstacles to the development of realistic simulation of deep earth processes. Realistic 4D thermo-mechanical simulation using software packages like Underworld and Gale, when combined appropriately with geoscientific expertise, can lead to novel insights into the deformation of geological structures at a wide range of time and spatial scales. The challenge for end-user geoscientists lies in applying their knowledge within the framework of the software’s input specification, including initial, internal, and boundary conditions and output visualization parameters. We have built a Graphical User Interface (GUI) to remove many of the difficulties related to editing the Extensible Markup Language (XML) encoded input files of Underworld/Gale geomodels and therefore, to greatly broaden the user base of these software packages. By helping Underworld/Gale to meet a large audience, we provide a tool to the geoscience community that helps to move from untested conceptual models to physically valid, properly scaled modelling. Furthermore, the UnderworldGUI offers a mechanism for storing and retrieving experimental models in a centralised database, thus providing the geoscience community with a means to share the outcomes of its experimental research. Further details of the UnderworldGUI are available at the web site http://www.wiki.vislab.usyd.edu.au/moinwiki/UnderworldGUI.     

Optimal investment sequence

Summary. This paper investigates the optimal order in which a collection of projects should be taken on if only one project can be done at a time. We associate a number called priority value with each project and show that one should order the projects in decreasing priority values. We also show that this priority value rule is equivalent to the replication rule in the literature. Finally, we compare the rankings given by the priority value rule and the ordinary present value rule.     

Uncertainty and implied variance bounds in long-memory models of the interest rate term structure

We find that long-term uncertainty in a linear model of the interest rate term structure can have dramatic effects on variance bounds implied by the expectations theories of the term structure. We bootstrap fractionally integrated models of the term structure of interest rates. The fractional order of integration's bootstrapped standard errors simulate uncertainty surrounding long-term forecasts of interest rates, and we find that it is possible to overstate the significance of variance-bounds violations by at least a factor of three and perhaps by a factor of ten when long-term uncertainty is ignored.I wish to thank Frank Diebold, Baldey Raj, Eric Renault, Fallaw Sowell and several anonymous referees for their comments and suggestions for earlier versions of this paper. The paper also benefited from comments made by many seminar participants at the World Econometric Congress, the European Econometric Society, and the American Finance Association meetings, the Board of Governors of the Federal Reserve System, the Ecole Nationale de la Statistique et de l'Administration Economique, and the departments of Finance and Statistics at Penn State University.     

如何利用CDS市场数据拟合不同存活率模型

信贷衍生工具评估的关键要素是违约时间模型。此类事件隐含的不确定性通过违约概率分布（也称为违约期限结构）模型获取,此模型对发行人在未来给定时间间隔内的违约概率进行建模。违约概率估算具有不同的类型：历史违约概率采用公司的信用等级转换或评分模型进行估算;结构模型综合市场以及资产负债表信息来计算违约概率;风险中性概率采用简化模型通过单纯的市场数据进行推导。     

On the Equivalence of Ad Valorem Tariffs and Specific Tariffs under Duopoly*

Using a quantity conjectural variation model, this paper examines whether an ad valorem tariff and a specific tariff are equivalent under duopoly. We show that if the average per‐unit import tax is the same for the two tariffs, domestic output will be smaller while foreign output will be larger under an ad valorem tariff. We further show that for any value of a specific tariff, there is a Pareto‐superior ad valorem tariff for all values of conjectural variation except in the case of perfect competition where the two tariffs are equivalent.