Continuous-time mean-variance portfolio optimization in a jump-diffusion market

In this paper, we take up an approach of (Lindberg, in Bernoulli, 15(2):464–474, 2009) who introduced a new parameterization of the Black–Scholes model that allows for an easy solution of the continuous-time Markowitz mean-variance problem. We generalize the results of (Lindberg, in Bernoulli, 15(2):464–474, 2009) to a jump-diffusion market setting and slightly correct the proof and the assertion of the main result. Further, we demonstrate the implications of the Lindberg parameterization for the stock price drift vector in different market settings, analyse the dependence of the optimal portfolio from jump and diffusion risk and finally indicate how to use the method. We particularly also show how the optimal strategy can be obtained with the restricted use of historical data.     

Business strategies and the transition to low‐carbon cities

Cities are key drivers of global climate change, with the majority of greenhouse gas (GHG) emissions being tied to urban life. Local actions to mitigate and adapt to climate change are essential for stabilization of the global climate and can also help to address other urban ecological problems such as pollution, decreasing biodiversity, etc. Companies are important urban actors in the development of low‐carbon cities because they provide a multitude of goods and services to city populations and directly influence urban carbon dioxide (CO₂) emissions. This is a new area of research. While studies on corporate sustainability are numerous, there is little, if any, existing research that examines the role of companies in climate change adaptation and mitigation within specific urban areas. Urban ecologists also have not examined how corporate activity affects urban systems. Taking a multi‐disciplinary systems approach, we present a conceptual model of the role of companies in managing urban interactions with the climate system. We also present empirical findings illustrating how one company ‘partners’ with the city of Rotterdam to test electric vehicles as a pilot project for urban climate adaptation and mitigation. Copyright © 2010 John Wiley & Sons, Ltd and ERP Environment.     

Structuring of temporary multi‐organizations: Contingency theory in the building sector

The appropriate management of construction projects presupposes a clear comprehension of the structure of the temporary multi‐organization (TMO); however, most of the work on the structuring of TMOs has concentrated either on procurement strategies or the structure of individual organizations. Current approaches, therefore, do not fully consider the roles of all project stakeholders, the informal communications, and the complexity of the client organization. Instead, we argue that the contingency theory contributes to the understanding of the structuring of TMOs. The analysis of 27 recent construction projects allows us to identify two contingency factors and patterns of configuration of the TMO.     

ECONOMIC RECESSIONS,BANKING REFORM AND THE FUTURE OF CAPITALISM1

In the 2010 London School of Economics and Political Science Hayek Memorial Lecture, the author argues that flaws in the design of the monetary and financial system were responsible for the global financial crisis and the subsequent recession. The crash reflected the unsustainable nature of the bubble induced by artificial credit expansion created by fractional‐reserve banking under the direction of central banks. Such boom–bust cycles will continue until radical reforms are implemented, including a 100% reserve requirement for demand deposits.     

Pricing, learning, and strategic behavior in a single-sale model

Summary. We analyze an infinite horizon model where a seller who owns an indivisible unit of a good for sale has incomplete information about the state of the world that determines not only the demand she faces but also her own valuation for the good. Over time, she randomly meets potential buyers who may have incentives to manipulate her learning process strategically. We show that i) the seller's incentives to post a high price and to experiment are not necessarily monotonic in the information conveyed by a buyer's rejection; and ii) as the discount factors tend to one, there are equilibria where the seller always ends up selling the good at an ex-post individually rational price. Received: January 6, 1999; revised version: July 15, 2000     

Ramsey policies in a small open economy with sticky prices and capital

This paper analyzes jointly optimal fiscal and monetary policies in a small open economy with capital and sticky prices. We allow for trade in consumption goods under perfect international risk-sharing. We consider balanced-budget fiscal policies where authorities use distortionary taxes on labor and capital together with monetary policy using the nominal interest rate. First, as long as a symmetric equilibrium is considered, the steady state in an open economy is isomorphic to that of a closed economy. Second, sticky prices’ allocations are almost indistinguishable from flexible prices allocations both in open and closed economies. Third, the open economy dimension delivers results that are qualitatively similar to those of a closed economy but with significant quantitative changes. Tax rates are both more volatile and more persistent to undo the distortions implied by terms of trade fluctuations.     

Technical Efficiency of the Brazilian Municipalities: Correcting Nonparametric Frontier Measurements for Outliers

In this paper we estimate the DEA technical efficiency for 4796 Brazilian municipalities, by applying a recently proposed “Jackstrap” method, which combines Bootstrap and Jackknife resampling techniques, to reduce the effect of outliers and possible errors in the data set. We perform calculations to identify and eliminate high leverage municipalities, using different variants of Data Envelopment Analysis (DEA), as well as Free Disposal Hull (FDH). Corroborating previous results, efficiency results for the Brazilian municipalities show a clear relationship between the size of the municipality and its efficiency scores. Indeed, under both DEA variants, smaller cities tend to be less efficient than larger ones hence indicating that the quality of the frontier adjustment improves significantly as the size of the municipality increases. We present arguments that may explain to some extent these findings, such as economies of scale and the excess spending due to revenue from royalties. However, such effects require further, more careful examination.     

Fiscal adjustments,labour market flexibility and unemployment

Using a panel of 17 countries for 1978–2009, we find that tax-driven consolidations increase unemployment by 0.25 percentage points. Labour market flexibility mitigates this: a one-point rise in the flexibility index reduces youth (long-term) unemployment by 0.6–0.7 (1.8–2.2) percentage points.     

An Introduction to the Patstat Database with Example Queries

This article provides an introduction to the Patstat patent database. It offers guided examples of 10 popular queries that are relevant for research purposes and that cover the most important data tables. It is targeted at academic researchers and practitioners who are willing to learn the basics of the database.     

Do stable strategic time periods exist? Towards new methodological and theoretical insights

This paper investigates a fundamental issue in the current research on strategic groups: the existence or non‐existence of the so‐called ‘stable strategic time periods’ (SSTPs). Our study provides new evidence by adding new methodological and theoretical insights. The research setting is the Spanish banking industry over a 15‐year period, 1983–1997. Unlike all prior longitudinal research that found SSTPs, the multi‐method procedure that we used in this study (i.e. equality of variance and covariance matrix and mean vector of strategic variables and a subsequent grouping analysis performed through the MCLUST) has led us to reject the existence of SSTPs in the industry under study. Based on these original findings, we conclude by suggesting a proposition which should be corroborated in future empirical studies on strategic groups. Copyright © 2007 John Wiley & Sons, Ltd.