When does uncovered interest parity hold?

A consensus is emerging that returns to the currency carry trade are driven by two factors. One of these is probably consumption risk but there is widespread disagreement about the identity of the remaining factor. This paper bolsters the case for volatility being the unknown factor. A structural model that specifies that monetary volatility is the second factor is tested for 56 monetary regimes using the artificial economy methodology. The negative slope in the Fama regression arises when monetary volatility is low and the precautionary savings motive dominates the intertemporal substitution motive. When monetary volatility is high, the Fama slope is positive in line with uncovered interest parity. We conclude that, given the predominance of precautionary savings, the degree of monetary volatility explains whether uncovered interest parity holds.     

Cost-effectiveness of Access to Critical Cerebral Emergency Support Services (ACCESS): a neuro-emergent telemedicine consultation program

Aims: Access to Critical Cerebral Emergency Support Services (ACCESS) was developed as a low-cost solution to providing neuro-emergent consultations to rural hospitals in New Mexico that do not offer comprehensive stroke care. ACCESS is a two-way audio-visual program linking remote emergency department physicians and their patients to stroke specialists. ACCESS also has an education component in which hospitals receive training from stroke specialists on the triage and treatment of patients. This study assessed the clinical and economic outcomes of the ACCESS program in providing services to rural New Mexico from a healthcare payer perspective.

Methods: A decision tree model was constructed using findings from the ACCESS program and existing literature, the likelihood that a patient will receive a tissue plasminogen activator (tPA), cost of care, and resulting quality adjusted life years (QALYs). Data from the ACCESS program includes emergency room patients in rural New Mexico from May 2015 to August 2016. Outcomes and costs have been estimated for patients who were taken to a hospital providing neurological telecare and patients who were not.

Results: The use of ACCESS decreased neuro-emergent stroke patient transfers from rural hospitals to urban settings from 85% to 5% (no tPA) and 90% to 23% (tPA), while stroke specialist reading of patient CT/MRI imaging within 3?h of onset of stroke symptoms increased from 2% to 22%. Results indicate that use of ACCESS has the potential to save $4,241 ($3,952–$4,438) per patient and increase QALYs by 0.20 (0.14–0.22). This increase in QALYs equates to ～73 more days of life at full health. The cost savings and QALYs are expected to increase when moving from a 90-day model to a lifetime model.

Conclusion: The analysis demonstrates potential savings and improved quality-of-life associated with the use of ACCESS for patients presenting to rural hospitals with acute ischemic stroke (AIS).     

Aggregation and misspecification biases in estimates of factor elasticity of substitution: The case of Egypt

Zusammenfassung Aggregations- und Fehlspezifikationsverzerrungen in Sch?tzungen der Substitutionselastizit?t: das Beispiel ?gyptens. — In den letzten Jahren nahm mit der Anzahl der Arbeiten, die über die Substitutionselastizit?t der Produktionsfaktoren in Entwicklungsl?ndern berichten, auch die Notwendigkeit zu, diese Sch?tzungen auf Verzerrungen durch Aggregation und Fehlspezifikation zu testen. Verzerrungen durch Aggregation kommen zustande, wenn zwei Unternehmen mit unterschiedlichen Produktionsfunktionen zusammengefa\t und so behandelt werden, als h?tten sie dieselbe spezifische Produktionsfunktion. Um die Gültigkeit einer solchen Methode zu prüfen, wurde die Substitutionselastizit?t 1. für kleine, 2. für gro\e und 3. für alle Unternehmen gesch?tzt. Die Ergebnisse zeigen deutlich, da\ jede Gruppe durch einen eigenen Elastizit?tsparameter gekennzeichnet ist. Deshalb dürfte die generelle Praxis, die Eigenschaften einer aggregierten Produktionsfunktion zu verallgemeinern und bei allen Unternehmen, unabh?ngig von ihrer Gr?\e, vorauszusetzen, in der Tat irreführend sein. Im zweiten Teil der Untersuchung wird versucht, die Verzerrungen durch Fehlspezifikation zu sch?tzen, die aus den Annahmen entstehen, da\ ?konstante Skalenertr?ge? und vollkommene M?rkte gegeben sind. Die Ergebnisse zeigen, da\ bei der Annahme konstanter Skalenertr?ge der relative Einflu\ der unberücksichtigten Variablen (Besch?ftigung) den Wert des Parameters für die Substitutionselastizit?t verzerrt, d.h. erh?ht. Andererseits kann die Annahme eines vollkommenen Wettbewerbs dazu führen, da\ die Verzerrung in den typischerweise kleineren Konsumgüterindustrien wesentlich kleiner ist als in den gr?\eren Kapitalgüterindustrien. Aus der Untersuchung geht zugleich hervor, da\ eine Faktorsubstitution in der verarbeitenden Industrie ?gyptens tats?chlich stattfindet. Bei jedem Aggregationsgrad weisen die Sch?tzungen der Substitutionselastizit?t nach Eliminierung verschiedener Ursachen der Spezifikationsverzerrungen im Durchschnitt Werte auf, die signifikant von Null verschieden sind.

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Résumé Les biais de l’agrégation et de la fausse spécification dans les estimations de l’élasticité de substitution des facteurs: le cas de l’Egypte. — Pendant que le nombre d’articles avec des estimations de l’élasticité de substitution des facteurs (ESF) pour des pays en voie de développement augmentait de plus en plus au cours des années récentes, l’importance aggrandissait aussi de tester les biais qui résultent de l’agrégation et d’une fausse spécification. Les biais de l’agrégation se forme si deux établissements qui possèdent des fonctions de production différentes sont mis ensemble et considérés comme d’avoir les mêmes fonctions de production spécifiques. Afin de tester le bien-fondé d’une telle procédure, l’auteur a estimé ESF pour tous les établissements, ainsi que pour les établissements de petite et grande taille. Les résultats indiquent clairement que chaque groupe est caractérisé par un paramètre d’élasticité bien différent. Par conséquent, l’habitude de généraliser les résultats obtenus des fonctions de production industrielle agrégées sans égard pour la taille des établissements peut, en effet, conduire à des fausses conclusions. La deuxième partie de cette étude est consacrée à estimer les biais d’une fausse spécification qui résultent si l’on suppose de fa?on explicite des rendements d’échelle constants et des marchés parfaits. En ce qui concerne la première supposition, les résultats montrent que l’influence relative de la variable omise (l’emploi du travail) est reflétée sur le paramètre de ESF en lui donnant un biais en haut. De l’autre c?té, la deuxième supposition tend à produire des biais significativement plus petits dans les industries des biens de consommation et de petite taille que dans les industries des biens de production et de grande taille. De cette étude, il en résulte aussi la conclusion générale que la substitution des facteurs dans le secteur manufacturier est un fait économique en Egypte. Les estimations de ESF étaient, en moyenne, significativement différentes de zéro sur chaque niveau de l’agrégation, après qu’on avait éliminé plusieurs sources de biais d’une fausse spécification.

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Resumen Problemas de agregación y especificación en la estimatión de elasticidades de sustitución de factores: el caso de Egipto. — En vista del creciente número de estudios recientes dedicados a la estimatión de elasticidades de sustitución en países en desarrollo, parece oportuno ocuparse de los sesgos cometidos en la medición de los parámetres como consecuencia de los problemas de agregación y especificación de la función de productión correspondiente. El présente artículo trata de examinar estos problemas, primero a nivel teórico y luego a nivel empírico sobre la base de datos egipcios en corte trasversal. El sesgo de la agregación surge cuando dos empresas o industrias con distintas funciones de productión son tratadas, a nivel global, como teniendo la misma función de productión. El autor estudia este problema mediante la estimatión de elasticidades de sustitución para tres grupos de industrias: de tama∼no peque∼no las unas, de tama∼no grande las otras, y todas juntas formando el tercer grupo. Los resultados obtenidos claramente indican que los parámetros de elasticidad difieren de un grupo a otro. Esto significa que el procedimiento tradicional de generalizar sobre la base de funciones agregadas de productión, haciendo caso omiso de diferencias en el tama∼no de las empresas o industrias, puede dar lugar a conclusiones equivocadas desde el punto de vista práctico. La segunda parte del articulo trata de estimar el sesgo de la especificación errónea que resulta de la rigidez de suponer rendimientos constantes de escala y condiciones de competencia perfecta. Los resultados obtenidos demuestran que la premisa de rendimientos constantes de escala da lugar a que la variable omitida (por ejemplo el empleo de trabajadores) influencia el valor de la elasticidad de sustitución y lo sesga hacia arriba. Por otro lado, el supuesto de libre concurrencia tiende a producir sesgos significativamente menores en industrias peque∼nas y de consumo que en las grandes y de inversión. Una conclusión general de este estudio consiste en que la sustitución de factores de hecho existe en la industria manufacturera de Egipto. A cualquier nivel de agregación y después de eliminar las distintas fuentes de errores provenientes del problema de la especificación, los valores de las elasticidades siguen siendo, en promedio, significativamente diferentes de cero.

     

Optimal Redistribution with Heterogeneous Preferences for Leisure

This paper examines the properties of the optimal nonlinear income tax when preferences are quasi–linear in leisure and individuals differ in their ability and their preferences for leisure. The government seeks to redistribute income. It can perfectly observe the level of endogenous income but cannot observe either ability or preferences. The heterogeneity of preferences leads to problems of comparability between individual utilities which challenge the design of redistributive schemes. We analyze the consequences of adopting a utilitarian social welfare function where the government is allowed to give different weights to individuals with different preferences. Under this particular social objective and given the quasi–linearity of preferences, we are able to obtain closed–form solutions for the marginal tax rates and to examine the progressivity of the tax system according to the weights used.     

Interregional redistribution through tax surcharge

The paper considers a utilitarian federal government that levies a tax to finance a national public good or to effect a redistributive policy. Regions differ in their incomes and in their preferences for a local public good. First, we assume that the central government observes each region's public expenditures (and, hence, local tax revenues) but cannot perfectly observe revenues and preferences. We derive the (constrained) Pareto-efficient allocation and show how it can be implemented by a surcharge on local taxes. The level of redistribution that can be achieved is limited by the fact that it may be difficult, or even impossible, to distinguish low-income regions with a high preference for the public good from high-income regions with a low preference. Then we allow for the possibility that the central government can observe incomes through a costly audit. We examine the optimal audit policy and study the impact of audits on the optimal taxation scheme. Throughout the paper we focus on the properties of average and marginal tax rates and on the resulting under- or overprovision of regional public goods.     

On `indirect' trade-related R&D spillovers

An influential literature argues that trade promotes knowledge flows and technology transmission between trading partners. This literature focuses on `direct' research and development (R&D) spillovers which are related to the levels of R&D produced by the trading partners. In this paper, we argue that `indirect' trade-related R&D spillovers also take place between countries, even if they do not trade with each other. These `indirect' spillovers are associated with available rather than with produced levels of R&D. Our empirical results suggest that these `indirect' trade-related spillovers are at least as important as the `direct' ones, and strengthen the view that trade does matter for the international transmission of R&D. They also suggest that, due to the existence of these `indirect' effects, bilateral trade patterns are relatively less important determinants of the level of foreign R&D spillovers acquired through trade.     

The United States International Air Route Award Process: Shareholder Wealth Effects and Policy Implications

This study empirically investigates the market pricing dynamics of United States airline stocks in response to United States government allocations of exclusive, zero-priced international air route awards from the 1963 to 1993 time period. A $900 filing fee required by the Department of Transportation represents the only explicit monetary cost associated with the award of an international air route. This low fee suggests that the current award system subsidizes United States airlines by transferring valuable public property rights to private ownership and control for paltry explicit fees. The performed dollar abnormal tests suggest that the 82 analyzed international air routes have enriched airline shareholders by about $3.5 billion.