Covariance Stationarity of International Equity Markets Returns: Recent Evidence

Intertemporal stationarity tests of the variance-covariance matrix of monthly returns on seven international equity indices are conducted over the most recent period. Pairwise covariances are then decomposed into their component statistics for further examination of the source(s) of stationarity or nonstationarity. Historical analysis reveals that pairwise covariances were invariably highly nonstationary over forecast intervals that varied in length between one month and five years. Reliance on historical covariances to estimate future covariances over a hold-out sample produced suboptimal results in comparison to an alternative naive forecasting model. These findings were robust in that they were invariant to whether nominal or real returns were used. Evidence on the intertemporal stationarity of the vector of mean returns is also provided.     

R&D,Human Capital and Export Behavior of Manufacturing and Service Firms in Ghana

ABSTRACT

The paper carries out a detailed analysis of the effects of R&D and human capital as well as their interactions with innovation on export behavior of manufacturing and service firms in Ghana using a dataset of 720 firms that merges the Enterprise, Innovative Capability and the Innovation Follow-up Surveys respectively for Ghana. Using a bivariate probit regression, the results show that R&D and human capital (employees’ education, slack time and formal training) are positive and significantly related to the propensity for firms to export in Ghana. The cross derivatives (differences) for the interaction terms (R&D and innovation, and education and innovation) also showed that these interaction terms have positive effects on the likelihood for firms to export but are significant only for a negligibly small fraction of the sample. Thus, there is no much statistically significant evidence in support of the mediation role of innovation in the relationship between R&D/education and the export behavior.     

Economic growth and government expenditure: evidence from a new test specification

A new test specification of Wagner's Law of Public Expenditure has been formulated. The aim is to disentangle the effects of accelerating and decelerating economic growth on growth in government expenditure. Two alternative proxies for the state of the economy are experimented with. The first defines the current state of the economy by relating it to its historical mean growth rate, while the second defines it relative to a pooled time-series/cross-sectional mean growth rate. This distinction is then explicitly incorporated into an error correction model that parameterizes the bivariate relation between government expenditure and economic growth for alternative OECD country groupings. The results suggest that government expenditure increases less than proportionately with accelerating economic growth and decreases more than proportionately with decelerating economic growth. There is only a limited support for Wagner's Law.     

Remittances and output in Bangladesh: an ARDL bounds testing approach to cointegration

Although the relationship between remittances and output is still inconclusive in literature, most studies find that remittances have a positive effect on output in the long run. Contrary to this conventional direction of causality from remittances to output, our study finds that output alone determined long-run movements in remittances in a positive direction in the Bangladesh economy over the last 35 years from 1976 to 2010. We use the autoregressive distributive lag (ARDL) bounds testing approach to cointegration to explore this long-run relationship. Surprisingly, remittances do not appear to be a long-run forcing variable to the explanation of Bangladesh’s output over the same period. While examining the channels of this output–remittance mechanism remains an area of research for the future, we hypothesize that the rise in remittances in response to increased income occurs through higher import demand and greater investment opportunities. This finding implies that Bangladeshi policymakers can influence remittances through national output in the long run.     

Are exports a reliable source of economic growth in MENA countries? New evidence from the rolling Granger causality method

Empirical Economics - Earlier investigations have concentrated on the effect of export expansion on economic growth while ignoring the importance of the stability of such relationship. This paper...     

The Minimal Entropy Martingale Measure (MEMM) for a Markov-Modulated Exponential Lévy Model

This paper deals with the characterization problem of the minimal entropy martingale measure (MEMM) for a Markov-modulated exponential Lévy model. This model is characterized by the presence of a background process modulating the risky asset price movements between different regimes or market environments. This allows to stress the strong dependence of financial assets price with structural changes in the market conditions. Our main results are obtained from the key idea of working conditionally on the modulator-factor process. This reduces the problem to studying the simpler case of processes with independent increments. Our work generalizes some previous works in the literature dealing with either the exponential Lévy case or the exponential-additive case.     

Islamic takaful: Business models,Shariah concerns,and proposed solutions

Islamic insurance (takaful) is nearly as old as the Islamic banking system and dates back to 1979, when the concept was launched in Sudan and later in Saudi Arabia. Yet, unlike its banking counterpart, takaful has been covered less in the literature on Islamic finance, and its workings are not fully understood. Shariah scholars have raised a num‐ber of concerns about the Shariah permissibility of the business models employed in the industry. This article examines the basic principles of takaful and then analyzes the mechanics of the two models most commonly used in the industry— namely, the mudarabah system that was developed by the Malaysians and the wakala (agency) system that is now being used by most takaful operators and has achieved tremendous popularity and acceptance in recent years even in countries where the mudarabah model was earlier implemented. Shariah scholars have, however, expressed some misgivings about both approaches, but because of its wider acceptability among Shariah scholars in the case of the wakala approach, this is more urgent. With regards to the mudarabah model for risk management, there are major discrepancies that have been highlighted by Shariah scholars effec‐tively rendering it inappropriate to apply this for insurance contracts. For this reason, the article outlines a third model, a wakala with waqf fund, that seeks to remain within the wakala framework while incorpo‐rating modifications that may render it more acceptable from a Shariah perspective. © 2007 Wiley Periodicals, Inc.