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31.
Abstract. During the last decade, many Western economies reformed their welfare systems with the aim of activating welfare recipients by increasing welfare‐to‐work programmes (WTWP) and job‐search enforcement. We evaluate the short‐term effects of three important German WTWP implemented after a major reform in January 2005 (‘Hartz IV’), namely short training, further training with a planned duration of up to three months and public workfare programmes (‘One‐Euro‐Jobs’). Our analysis is based on a combination of a large‐scale survey and administrative data that is rich with respect to individual, household, agency level and regional information. We use this richness of the data to base the econometric evaluation on a selection‐on‐observables approach. We find that short‐term training programmes, on average, increase their participants' employment perspectives. There is also considerable effect heterogeneity across different subgroups of participants that could be exploited to improve the allocation of welfare recipients to the specific programmes and thus increase overall programme effectiveness.  相似文献   
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We show that some care is needed when inferring true unconditional correlations from observed conditional correlations, which is a frequent problem in empirical finance and elsewhere. We give a general formula for the relationship between the two and demonstrate its importance in the context of the bivariate t-distribution.  相似文献   
33.
THE REGULATION OF INTERNATIONAL BANKING, by Richard Dale ECONOMIC FORECASTING AND POLICY: THE INTERNATIONAL DIMENSION, by John Llewellyn, Stephen Potter and Lee Samuelson  相似文献   
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Experience has shown that a Distributed Control System (DCS) can provide enhanced process monitoring and control capabilities, as well as system self-diagnostics, that permit increased safety of process operations. However, this enhanced safety does not come about automatically with the installation of a DCS. The complexity and versatility of the DCS can introduce new failure scenarios leading to process upset and potential relization of process hazards. This paper reviews some novel considerations that should be taken into account when conducting process hazards reviews on facilities controlled by a DCS.  相似文献   
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An integrated methodological framework for ex-ante evaluation and planning of public policies for sustainable agriculture at agro-landscape level is proposed. The components of the framework are to: (1) determine the private, i.e. farmers’, and public benefits associated to agro-landscapes, consisting of an agricultural land-use system, according to its performance for several market and non-market functions. Market forces determine the market benefits and preferences of society the non-market benefits; (2) explore and select potential sustainable agro-landscapes based on the private and public benefits associated with possible land-use alternatives; (3) define efficient public policy mechanisms for improving social net benefit of agro-landscapes.The framework is illustrated with a case study in a small dairy farming dominated agro-landscape in The Netherlands, with gross margin, landscape quality, nature value and environmental health as the analysed ecosystem functions. Alternative landscapes consisting of hedgerow configurations and grassland management practices were explored, yielding a set of alternatives representing the solution space in terms of change in private and public benefits. Policy mechanisms were defined to move from the current to a desired landscape based on changes in social net benefits. Moreover, the necessity of a modification in the current agri-environmental support was analysed for each landscape. The analysis considered all farmers in the agro-landscape jointly. The results for the case study showed potential prototypes of landscapes and their performance compared to the current landscape. Extension was the most efficient policy mechanism to promote the change to the socially optimum landscape alternative.  相似文献   
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Soil water and nutrients are critical drivers of crop production for smallholders of southern Africa. A three-year study was conducted to assess the effect of integrating single and double ploughing, ripping and planting basins with nitrogen fertilizer (0, 10 and 20?kg?N?ha–1) on soil water dynamics and maize (Zea mays L.) yields. The experimental design was factorial with four tillage methods and three nitrogen levels as treatment factors. The study was conducted under semi-arid conditions of Zimbabwe. Tillage methods had similar soil water patterns in the profile and no tillage?×?N interaction effects were observed on soil water dynamics. Soil water penetrated deeper into the profile under ripper and basin methods than conventionally ploughed treatments. Nitrogen increased maize yields (14–96%) and rainwater-use efficiency (20–92%) regardless of tillage methods and growing season quality. However, more studies are required to explore complementary techniques that can improve rainwater capture and prolong soil water storage, and improve soil fertility.  相似文献   
40.
Food expenditures, influenced by social, demographic, and economic factors, constitute a significant proportion of the typical rural Indian's household income. Based on cross‐sectional household data, this study employs the Quadratic Almost Ideal Demand System to estimate food demand among rural Indian households. Special attention is given to the rural household's two‐stage budgeting in total food expenditure and then to a demand for a specific food item. Conditional and unconditional expenditure and price elasticities for seven food groups are estimated. Results indicate that own‐price elasticities for each group are negative ranging from fairly inelastic to elastic range. Expenditure elasticities indicate that food items are a normal necessity to luxury goods. Additionally, socio‐demographic factors play a significant role in food consumption patterns. Based on our unconditional expenditure elasticities, we also project food demand from rural Indian households for next two decades. Les dépenses alimentaires, qui sont influencées par des facteurs socioéconomiques et démographiques, absorbent une partie considérable du revenu des ménages ruraux typiques en Inde. Dans la présente étude, nous avons utilisé le modèle de demande quasi idéal quadratique pour estimer, à l'aide de données transversales sur les ménages, la demande alimentaire des ménages ruraux en Inde. Nous avons accordé une attention spéciale à la budgétisation en deux étapes des dépenses alimentaires totales et à la demande d'un produit alimentaire particulier du ménage rural. Nous avons estimé les dépenses conditionnelles et inconditionnelles et l’élasticité‐prix de sept groupes alimentaires. Les résultats de notre étude indiquent que l’élasticité‐prix de chaque groupe est négative et qu'elle varie de plutôt inélastique à divers degrés d’élasticité. L’élasticité des dépenses indique que les produits alimentaires varient de nécessités de base à produits de luxe. Les facteurs sociodémographiques jouent également un rôle important dans les habitudes de consommation alimentaire. D'après les élasticités des dépenses établies dans notre étude, nous avons estimé la demande alimentaire des ménages ruraux en Inde pour les deux prochaines décennies.  相似文献   
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