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991.
992.
Aflatoxins are a common health hazard in tropical countries, especially in rural areas. New methods to reduce aflatoxin levels in food staples, as well as cheaper test methods, are being developed, but consumers’ willingness to pay (WTP) for these improvements is unknown. A survey was conducted with a representative sample of rural consumers (1,344 in total, 63% women) in all major maize‐production zones of Kenya. The survey included an experimental auction with maize products of different qualities. The results showed that many rural consumers were aware of aflatoxins, but few understood their health risks. Respondents were willing to pay a premium for maize tested for aflatoxins and labeled, but asked a high discount for maize that was visibly contaminated with moldy grain. The premium was higher for respondents with education and in regions with aflatoxicosis outbreaks. Knowledge of aflatoxins substantially reduced the overall WTP, but did not increase the WTP for tested maize. Welfare analysis indicates that mandatory testing would result in substantial benefits if the cost of testing can be lowered to below the premium.  相似文献   
993.
Most bank merger studies do not control for hidden bailouts, which may lead to biased results. In this study we employ a unique data set of approximately 1000 mergers to analyze the determinants of bank mergers. We use undisclosed information on banks’ regulatory intervention history to distinguish between distressed and non-distressed mergers. Among merging banks, we find that improving financial profiles lower the likelihood of distressed mergers more than the likelihood of non-distressed mergers. The likelihood to acquire a bank is also reduced but less than the probability to be acquired. Both distressed and non-distressed mergers have worse CAMEL profiles than non-merging banks. Hence, non-distressed mergers may be motivated by the desire to forestall serious future financial distress and prevent regulatory intervention.  相似文献   
994.
Evaluating the impact of rising fertilizer prices on crop yields   总被引:3,自引:0,他引:3       下载免费PDF全文
Because of tensions on fossil energy and phosphorus markets, the rise in fertilizer prices observed during the last decades may continue in the future, putting into question production pathways relying heavily on crop intensification. To evaluate how, in this context, economic choices may alter crop yields, we first construct different fertilizer price scenarios to 2050 based on an econometric relation with oil and gas prices. Other possible scenarios, such as the continuation of historical trends, are also considered. The resulting changes in fertilizer price range between +0.8% and +3.6% per year over the 2005–2050 period. These scenarios are tested in a global land‐use model incorporating an endogenous representation of the land–fertilizer substitution. We find that the supply‐side response to rising fertilizer prices could lower crop yields in 2050 from ?6% to ?13%, with a corresponding increase in global cropland area ranging between 100 and 240 Mha if the demand for food and nonfood products has to be met. The sensitivity of these results is tested with regard to assumptions on food consumption, change in potential yield and nutrient use efficiency.  相似文献   
995.
Plant-based precision nitrogen fertilizer application technologies have been developed as a way to predict and precisely meet nitrogen needs. Equipment necessary for precision application of nitrogen, based on sensing of growing wheat plants in late winter, is available commercially, but adoption has been slow. This article determines the expected profit from using a plant-sensing system to determine winter wheat nitrogen requirements. We find that plant-sensing systems have the potential to be more profitable than traditional nonprecise systems, but the existing system simulated was roughly breakeven with a traditional system.  相似文献   
996.
We study the interrelation between conservatism and earnings management by examining the allowance for uncollectible accounts and its income statement counterpart, bad debt expense. We find that the allowance is conservative and that it has become more conservative over time. Conservatism may, however, facilitate earnings management. We find that firms manage bad debt expense downward (and even record income‐increasing bad debt expense) to meet or beat analysts’ earnings forecasts and that conservatism accentuates the extent to which firms manage bad debt expense. Further, we find that firms manage bad debt expense downward by drawing down previously recorded over‐accruals of bad debt expense that have accumulated on the balance sheet. An implication of our study is that tighter limits on the amount by which firms are permitted to understate net assets may reduce their ability to manage earnings.  相似文献   
997.
998.
Low agricultural productivity remains the primary source of poverty in the developing regions and yet little is known about the influence on agricultural productivity of domestic and international accumulated R&D knowledge and the channels through which this knowledge is transmitted internationally. Following a large scientific literature, this article argues that R&D and R&D knowledge spillover are ecozone‐specific and, therefore, are transmitted internationally through ecozones, where ecozones are the broadest biogeographic division of the earth's land surface. Using data for a panel of 88 countries, it is shown that international knowledge spillovers are ecozone‐specific and have been an important contributing factor behind the marked widening of the income gap between developed and developing countries since 1983.  相似文献   
999.
This article aims to understand the relation between household food security and individual undernutrition. The multitude of indicators available raises the question which aspects of food security are captured by the respective indicator. In our analysis, we first assess the relation between the dimensions of food security and households’ socioeconomic characteristics. Second, we examine whether household indicators detect undernutrition in children. Finally, we investigate the role of individual‐specific characteristics for child undernutrition. The analysis is based on a novel data set of 1,200 rural households from Cambodia and Lao PDR, which combines household‐ and individual‐level data. We capture household food security by three indicators including a dietary diversity score, a consumption behavior measure, and an experiential measure. Individual nutrition status is measured via anthropometric indicators. Our results show that different household‐level indicators capture fundamentally different aspects of food security. Moreover, household food security fails to explain stunting for children under five. Dietary diversity indicators, however, explain underweight in children to a small extent. We call for more research on intrahousehold allocation of food and stress the implications of our research for the design and targeting of food and nutrition support programs.  相似文献   
1000.
Are farmers better stewards of the land they own than the land they rent from others? We answer this question using a data set that identifies Ontario farmers’ conservation practices on their own land as well as the land they rent. Using a fixed‐effects regression approach, we find that the role of tenure varies for different types of conservation practices. Farmers were found to be just as likely to adopt a machinery‐related practice such as conservation tillage on their rented land as that land which they own. On the other hand, farmers were found to be less likely to adopt site‐specific conservation practices such as planting cover crops on rented land. However, this effect diminishes as the expected length of the rental relationship increases when the landlord has a farming background.  相似文献   
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