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This paper examines whether the labor market prospects of Arab men in England are influenced by recent Islamistic terrorist attacks and the war on Iraq. We use data from the British Labour Force Survey from Spring 2001 to Winter 2006 and treat the terrorist attacks on the USA on September 11th, 2001, the Madrid train bombings on March 11th, 2004 and the London bombings on July 7th, 2005, as well as the beginning of the war on Iraq on March 20th, 2003, as natural experiments possibly having led to a change in attitudes toward Arab or Muslim men. Using treatment group definitions based on ethnicity, country of birth, current nationality, and religion, evidence from regression-adjusted di_erence-in-di_erences-estimators indicates that the real wages, hours worked and employment probabilities of Arab men were unchanged by the attacks. This finding is in line with prior evidence from Europe.
The paper demonstrates how the E–stability principle introduced by Evans and Honkapohja can be applied to models with heterogeneous and private information in order to assess the stability of rational expectations equilibria under learning. The paper extends already known stability results for the Grossman and Stiglitz model to a more general case with many differentially informed agents and to the case where information is endogenously acquired by optimizing agents. In both cases it turns out that the rational expectations equilibrium of the model is inherently E-stable and thus locally stable under recursive least squares learning.
El-Salam Canal Project aims at increasing the Egyptian agricultural productivity through agricultural and stock development by irrigating about 263,500 ha gross of new lands. In order to stretch the limited water supply to cover these reclaimed areas, fresh River Nile water is augmented with agriculture drainage water from Hadus and Lower Serw drains to meet crop requirements, especially during summer months (peak demand). With a growing population and intensified industrial and agricultural activities, water pollution is spreading in Egypt, especially in main drains, which receive almost all kinds of wastes (municipal, rural, domestic and industrial wastes). The medical records indicate that significant numbers of waterborne-disease cases (bilharzias, typhoid, paratyphoid, diarrhoea, hepatitis A, B and C) have been reported in many areas in Egypt (MOHP, 2000). The National Water Quality Monitoring Program (NWQMP) in Egypt covers the Nile River, irrigation canals, drains and groundwater aquifers to assess the status of water quality for different water uses and users. The overall objective of this research is to introduce a rationalization technique for the drainage water quality-monitoring network for Hadus drain as a main feeder of El-Salam Canal Project. Later on, this technique can be applied for other parts in the NWQMP. The rationalization process started firstly with assessing and reformulating the current objectives of the network. Then, the monitoring locations were identified using integrated logical and statistical approaches. Finally, a sampling frequency regime was recommended to facilitate proper and integrated information management. The monitoring objectives were classified into three classes: design oriented, short-term and long-term deductible objectives. Mainly, the objectives “assess compliance with standards”, “define water quality problems”, “determine fate and transport of pollutants”, “make waste-load allocations” and “detect possible trends” were considered in the redesign process of the network. A combination of uni-, bi-, and multi-variate statistical techniques supported by spatial and temporal analysis for the important tributaries (key players) in Hadus drain system, were used for locating the monitoring sites. The key players analysis was carried out in the light of monitoring objectives. As a result, the monitoring network was divided into three priority levels (Layers I, II and III) as following: Layer I: It has the highest priority level and includes eight monitoring locations Layer II: It has the second priority level and includes three monitoring locations Layer III: It has the lowest priority level and includes five monitoring locations Using the method proposed by Lettenmaier (1976), the sampling frequencies were initially estimated and then evaluated for 36 water quality parameters, which were collected on monthly basis during the period from August 1997 to January 2005. The evaluation process was carried out by generating new data sets (subsets) from the original data. Then, the common required statistics from the monitoring network were extracted. The information obtained from different data sets was assessed using visual and statistical comparisons. Three integrated validation methods were employed to ensure that any decisions concerning the proposed program would not affect its ability to accomplish the monitoring objectives. These validation methods employed: descriptive statistics, regression analysis and linear multiple regression in an integrated approach. The validation results ensured that excluding the monitoring locations in layer III did not significantly affect the information produced by the monitoring network. Therefore, a monitoring network including only 11 sites (out of 16) representing the layers I and II was recommended. Based on the evaluation of sampling frequencies, it is recommended to have 6 (instead of 12) samples per year for 18 water quality parameters (COD, TSS, TVS, N-NO3, Pb, Ca, Na, Cl, Visib, BOD, Cu, Fe, Mn, pH, TDS, K, SO4_m and DO). The measured parameter SO4m will automatically replace the SO4 (calculated). SAR and Adj. SAR also can be calculated from the other parameters. For the other fifteen parameters (Mg, EC, Br, Ni, Sal, Cd, TN, TP, Temp, Fecal, Coli and N-NH4, Zn, P and Turb), it is recommended to continue with twelve samples per year. These recommendations may ensure significant reduction in the total cost of the monitoring network. This facilitates a fiscal resource, which is a key prerequisite in developing a successful program. The rescued budget can be redirected to achieve better performance in terms of improving the current resources. In addition, a frame of stakeholders-participation mechanism was proposed to not only facilitate a better coordination among the Egyptian Ministries involved in the water sector but also guarantee effective landowners/farmers involvement. However, applying such a mechanism requires more detailed studies of all the previous experiences gained by many projects trying to achieve better integration between objectives, plans and activities for the different environmental institutions in Egypt.
Strong sustainability, according to the common definition, requires that different natural and economic capital stocks have to be maintained as physical quantities separately. Yet, in a world of uncertainty this cannot be guaranteed. To therefore define strong sustainability under uncertainty in an operational manner, we propose to use the concept of viability. Viability means that the different components and functions of a dynamic, stochastic system at any time remain in a domain where the future existence of these components and functions is guaranteed with sufficiently high probability. We develop a unifying and general ecological-economic concept of viability that encompasses the traditional ecological and economic notions of viability as special cases. It provides an operational criterion of strong sustainability under conditions of uncertainty. We illustrate this concept and demonstrate its usefulness by applying it to livestock grazing management in semi-arid rangelands.
Reviewing the development of network access charges in the German electricity market since 2002 reveals significant variation. While some firms continually increased or decreased their access charges, a variety of firms exhibited discontinuous behavior with price changes in both directions. From an economic viewpoint this price setting turbulence is astonishing because grid operators are non-contestable natural monopolists, which in this time period were regulated by Negotiated Third Party Access (NTPA). Depending on the effectiveness or ineffectiveness of NTPA, expected behavior would be either regulated average cost prices or monopoly prices, but not the observed turbulence. Although in 2005 NTPA scheme was replaced by a Regulated Third Party Access (RTPA) scheme with a regulator, an analysis of the factors influencing the price setting behavior within this period offers valuable information for the new regulator and the still discussed new incentive regulation, which is expected to start in 2009. Using multivariate estimations based on firm data covering the years 2000-2005, we test the hypotheses that asymmetric influence of regulatory threat, different cost and price calculation knowledge, strategic use of structural features and the obligation to publish specific access charges have influenced the electricity network access charges in Germany.
Agro-biodiversity can provide natural insurance to risk averse farmers. We employ a conceptual ecological-economic model to analyze the choice of agrobiodiversity by risk averse farmers who have access to financial insurance. We study the implications for individually and socially optimal agro-ecosystem management and policy design when on-farm agro-biodiversity, through ecosystem processes at higher hierarchical levels, generates a positive externality on other farmers. We show that for the individual farmer natural insurance from agro-biodiversty and financial insurance are substitutes. While an improved access to financial insurance leads to lower agro-biodiversity, the e_ects on the market failure problem (due to the external benefits of on-farm agro-biodiversity) and on welfare are determined by properties of the agro-ecosystem and agro-biodiversity’s external benefits. We derive a specific condition on agro-ecosystem functioning under which, if financial insurance becomes more accessible, welfare in the absence of regulation increases or decreases.
This paper discusses a model of vertical and horizontal product differentiation within the Dixit-Stiglitz framework of monopolistic competition. Firms compete not only in prices and horizontal attributes of their products, but also in the quality that can be controlled by R&D activities. Based upon the results of a general equilibrium model, intra-sectoral trade and the welfare implications of public intervention in terms of research promotion are considered. The analysis involves a numerical application to ten basic European industries.
This paper analyzes, within a regional growth model, the impact of productive governmental policy and integration on the spatial distribution of economic activity. Integration is understood as enhancing territorial cooperation between the regions, and it describes the extent to which one region may benefit from the other region’s public input, e.g. the extent to which regional road networks are connected. Both integration and the characteristics of the public input crucially affect whether agglomeration arises and if so to which extent economic activity is concentrated: As a consequence of enhanced integration, agglomeration is less likely to arise and concentration will be lower. Relative congestion reinforces agglomeration, thereby increasing equilibrium concentration. Due to the congestion externalities, the market outcome ends up in suboptimally high concentration.
This paper uses data from the German Socio-Economic Panel for the years 2000 to 2005 to study the earnings differential between self- and dependent employed German men. Constructing a counterfactual earnings distribution for the self-employed in dependent employment and using quantile regression decompositions we find that the earnings differential over the distribution cannot be explained by differences in endowments. Furthermore, low-earning self-employed could earn more in dependent employment. Finally, the observed earnings advantage for the self-employed at the top of the earnings distribution is not associated with higher returns to observable variables.
This paper contributes to the flourishing literature on exports and productivity by using a unique newly available panel of exporting establishments from the manufacturing sector of Germany from 1995 to 2004 to test three hypotheses derived from a theoretical model by Hopenhayn (Econometrica 1992): (H1) Firms that stop exporting in year t were in t-1 less productive than firms that continue to export in t. (H2) Firms that start to export in year t are less productive than firms that export both in year t-1 and in year t. (H3) Firms from a cohort of export starters that still export in the last year of the panel were more productive in the start year than firms from the same cohort that stopped to export in between. While results for West Germany support all three hypotheses, this is only the case for (H1) and (H2) in East Germany.