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A major concern about biofuels is that increasing biofuel feedstock demand reduces availability of crops for food and feed leading to higher food prices. This paper investigates relations between biofuel policies and prices of rapeseed, the major feedstock used for biodiesel production in Europe, and the impact of rapeseed prices on crop acreages in Germany and France. Biodiesel is an important biofuel in Europe, and Germany and France are the largest biodiesel producers in Europe. First, the various biofuel policies in Germany and France are discussed, followed by an analysis of their effects on rapeseed prices. Although theory indicates that such effects exist, we could not find empirical evidence for them. Second, using regional land use panel data from Germany and France we investigate empirically whether crop shares have been affected by rapeseed prices in the period 2000–2015 and whether these price effects changed because of biofuel policy changes. Results show that wheat shares in Germany and France did respond to rapeseed prices, but barley shares did not. Moreover, mandatory blending introduced in Germany in 2007 and production quotas introduced in France in 2005 led to a stronger effect of rapeseed prices on wheat shares, but again did not affect barley shares.  相似文献   
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64.
Sequestering carbon in forest ecosystems is important for mitigating climate change. A major policy concern is whether forests should be left unharvested to avoid carbon dioxide (CO2) emissions and store carbon, or harvested to take advantage of potential carbon storage in post-harvest wood product sinks and removal of CO2 from the atmosphere by new growth. The issue is addressed in this paper by examining carbon rotation ages that consider commercial timber as well as carbon values. A discrete-time optimal rotation age model is developed that employs data on carbon fluxes stored in both living and dead biomass as opposed to carbon as a function of timber growth. Carbon is allocated to several ecosystem and post-harvest product pools that decay over time at different rates. In addition, the timing of carbon fluxes is taken into account by weighting future carbon fluxes as less important than current ones. Using simple formulae for determining optimal rotation ages, we find that: (1) Reducing the price of timber while increasing the price of carbon will increase rotation age, perhaps to infinity (stand remains unharvested). (2) An increase in the rate used to discount physical carbon generally reduces the rotation age, but not in all cases. (3) As a corollary, an increase in the price of carbon increases or reduces rotation age depending on the weight chosen to discount future carbon fluxes. (4) Site characteristics and the mix of species on the site affect conclusions (2) and (3). (5) A large variety of carbon offset credits from forestry activities could be justified, which makes it difficult to accept any.  相似文献   
65.
High-wealth individuals are typically underrepresented or completely missing in population surveys. The lack of comprehensive national registers on high-wealth individuals in many countries challenged previous attempts to remedy this under-representation. In a novel research design, we draw on public data on the shareholding structures of companies as a sampling frame. Our design builds on the empirical regularity that high-wealth individuals are likely to hold at least part of their assets in the form of shareholdings. Based on data from over 270 million companies worldwide, we select all individuals who are both German residents and registered shareholders of companies. In a pretest, we interviewed 124 households from a gross sample of 2,000 anchor persons. Our analysis shows that values of shareholdings from register data highly correlate with individual ranks in the wealth distribution, that the quality of personal information, particularly the residential address, is sufficiently high for subsequent interviewing, and that the approach can fill a major data and research gap in the study of high-wealth individuals.  相似文献   
66.
Although research and development (R&D) is a key indicator of (technological) innovation, scholars have found mixed results regarding its effect on product innovation and firm performance. In this paper, we claim that variations in R&D effectiveness can be explained by changes in a firm’s social system, in particular in its management innovation. It is still unclear how management innovation influences R&D effectiveness in terms of product innovation. In this study, we address this theoretical and empirical gap in the innovation literature. Our theoretical arguments and findings from a large-scale survey among Dutch firms show that R&D has a decreasingly positive relationship with product innovation, particularly for firms with low levels of management innovation. However, in firms with high levels of management innovation, this relationship becomes more J-shaped, especially in small and medium-sized firms. Our findings also appear to indicate that management innovation may be more important for competitive advantage than just R&D. Overall, our insights reveal that management innovation is a key moderator in explaining firms’ effectiveness in transforming R&D into successful product innovation.  相似文献   
67.
The aim of the paper is to quantify endogenous factor-augmenting technical change driven by R&D investments in a panel of 11 OECD countries over 1987–2007. This paper contributes to the scant empirical evidence on the speed, sources and direction of technical change for various sectors and production factors. Assuming cost-minimization behavior, a CES framework is used to derive a system of equations that is estimated by a GMM system estimator. The estimated factor-augmenting technology parameters show that in most sectors, technical change was labor-augmenting and labor-saving. Statistically significant effects of manufacturing and services R&D were found on factor-augmenting technical change (with the highest R&D elasticities found in the high-tech manufacturing and transport, storage and communication sectors). Whereas ‘in-house’ R&D stimulates total factor productivity, R&D spilled over to other sectors has a capital-augmenting effect accompanied by a higher use of labor. The results of this study provide a starting point for incorporating endogenous factor-augmenting technical change in impact assessment models aimed at broad policy analysis including economic growth, food security or climate change.  相似文献   
68.
Participatory arrangements have become a popular way of addressing modern challenges of urban governance but in practice face several constraints and can trigger deep tensions. Facilitative leadership can play a crucial role in enabling collaboration among local stakeholders despite plural and often conflictual interests. Surprisingly, this style of leadership has received limited attention within debates linking urban governance and participatory democracy. We summarize the main insights of the literature on facilitative leadership and empirically develop them in the context of participatory urban governance by comparing recent participatory processes in two Italian cities. Whereas in one city facilitative leadership gradually emerged and successfully transformed a deep conflict into consensual proposals, in the other city, participatory planning further exacerbated pre‐existing antagonism, and local democratic culture was only later slowly reinvigorated through bottom‐up initiative. These diverging pathways explain how facilitative leadership is: (1) important for making things happen; (2) best understood as situated practices; (3) an emergent property of the practices and interactions of a number of local actors and (4) a democratic capacity for dealing with continuous challenges. Key to this style of leadership is understanding participatory urban governance as an ongoing democratic process.  相似文献   
69.
This paper compares the production technology and production risk of organic and conventional arable farms in the Netherlands. Just–Pope production functions that explicitly account for output variability are estimated using panel data of Dutch organic and conventional farms. Prior investigation of the data indicates that within variation of output is significantly higher for organic farms, indicating that organic farms face more output variation than conventional farms. The estimation results indicate that in both types of farms, unobserved farm‐specific factors like management skills and soil quality are important in explaining output variability and production risk. The results further indicate that land has the highest elasticity of production for both farm types. Labour and other variable inputs have significant production elasticities in the case of conventional farms and other variable inputs in the case of organic farms. Manure and fertilisers are risk‐increasing inputs on organic farms and risk‐reducing inputs on conventional farms. Other variable inputs and labour are risk increasing on both farm types; capital and land are risk‐reducing inputs.  相似文献   
70.
Warmer temperatures and a decrease in precipitation in the 21st century could severely deplete wetlands in the prairie pothole region of western Canada. In this study, we employ linear regression analysis to determine the casual effect of climate change on wetlands in this region, with temperature, precipitation and the standardized precipitation index (SPI) used to predict the effect of potential climate change on wetlands. We then use a waterfowl-wetlands bioeconomic model to solve for socially optimal levels of duck harvests and wetlands retention under current climate conditions and various climate change scenarios. The model maximizes benefits to hunters plus the amenity values of ducks to non hunters and the non-market ecosystem benefits of wetlands. Results indicate that climate change could decrease wetlands by between 7 and 47%, and that the optimal number of wetlands to retain could decrease by as much as 38% from the baseline climate.  相似文献   
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