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111.
大气污染对人体健康影响的经济损失研究   总被引:3,自引:0,他引:3  
采用修正人力资本法,分析大气污染对人体健康影响的经济损失的影响因素,估算大气污染引起的过早死亡人力资本损失和大气污染造成的慢性支气管炎发病人力资本损失,并以广东省为例,估算出大气污染对人体健康影响的经济损失约为112.1亿元。  相似文献   
112.
Narrowing the gender technology gap in agricultural production has become a critical policy issue in sub‐Saharan Africa. A better understanding of the gender technology gap is essential for policy formulation and programme planning to ensure equity in resource allocation, and household‐level food security in low and middle income countries, such as Ghana. We employ a metafrontier approach to analyse the differences in the efficiency of male and female farmers, recognising the endogeneity of some of the variables in the inefficiency effects model, in particular the credit constraints of the rice farmers under study. Our findings show that while the rice farms themselves are very similar, average yields for male managed farms tend to be significantly higher than female managed farms reflecting higher seeding and fertiliser application rates on male managed farms. However, there is no significant difference between the genders in either land used for rice or total output per farm household. We find some evidence that relative to the metafrontier, male managed farms are less efficient than female managed farms. The results further show gender technology gap amongst the smallholder rice farmers with females’ technology gap ratio being significantly greater than that of males, with females operating on a production frontier closer to the metafrontier. Policies that provide females more access to productive resources and other agricultural services could assist in the generation of relatively higher output.  相似文献   
113.
The univariate statistical properties of agricultural price series need to be examined as a first step in the analysis of price transmission mechanisms. However, in the case of weekly price series, increasingly available, the testing procedures usually applied in this step are not suitable to deal with evolving seasonal effects. In this study, a method of testing for seasonal unit roots in weekly series of agricultural prices is described. When the deterministic seasonal component does not remain constant over time, the restricted evolving spline model (RESM) is shown to be a useful parametric formulation to capture the deterministic seasonal pattern. Therefore, the RESM model should be included as a deterministic component in auxiliary regression for unit root tests at seasonal frequencies. This proposal is applied to three weekly series of Canary Islands banana prices. From the standard seasonal unit root tests, the null hypothesis is failed to be rejected at the 5% or 10% significance level at some seasonal frequencies for each one of the series. Once critical values are obtained by simulation exercises when the RESM model is included, the hypotheses of unit root are rejected at each one of the seasonal frequencies for all of the three series.  相似文献   
114.
115.
This article revisits a conventional wisdom that inorganic fertiliser use across sub‐Saharan Africa is too low. This expectation that more farmers should be using inorganic fertiliser, and at higher rates, implies it is profitable to use rates higher than observed if farmers are rational expected profit maximisers. We obtain consistent estimates of the effects of applied nitrogen on rice production. We find the yield response to applied nitrogen to be low in the main rice growing farming system. Farmer behaviour is not inconsistent with expected profitability which is limited by a low yield response to applied fertiliser, high transportation costs, and low selling prices for rice in rural areas. In particular, we do not find any farmers for whom applied nitrogen is profitable that are not using fertiliser in the study sample for each of our survey years (2010 and 2012).  相似文献   
116.
We assess the impact of a potential TTIP bilateral free trade agreement on the EU and US bio‐economies (feedstock, biofuels, by‐products, and related competing crops) and major trade partners in these markets. The analysis develops a multi‐market model that incorporates bilateral trade flows (US to EU, EU to US, and similarly with third countries) and is calibrated to the OECD‐FAO baseline for 2013–2022 to account for recent policy decisions. The major policy reforms from a TTIP involve tariff and TRQ liberalisation and their direct contractionary impact on US sugar supply, EU biofuel production, and indirect negative effect on US high fructose corn syrup (HFCS) production. EU sugar and isoglucose production expand along with US ethanol and biodiesel and oilseed crushing. EU sugar would flow to the US, US biofuels and vegetable oil to the EU. We further quantify non‐tariff measures (NTM) affecting these trade flows between the EU and the US. EU oilseed production contracts, and EU crushing expands with improving crushing margins following reduced NTM frictions. Our analysis reveals limited net welfare gains with most net benefits reaped by Brazil and not the two trading partners of the TTIP.  相似文献   
117.
This paper explores farmers’ willingness to adopt genetically modified (GM) oilseed rape prior to its commercial release and estimates the ‘demand’ for the new technology. The analysis is based upon choice experiments with 202 German arable farmers. A multinomial probit estimation reveals that GM attributes such as gross margin, expected liability from cross pollination, or flexibility in returning to conventional oilseed rape significantly affect the likelihood of adoption. Neighbouring farmers’ attitudes towards GM cropping and a number of farmer and farm characteristics were also found to be significant determinants of prospective adoption. Demand simulations suggest that adoption rates are very sensitive to the profit difference between GM and non‐GM rape varieties. A monopolistic seed price would substantially reduce demand for the new technology. A monopolistic seed supplier would reap between 45% and 80% of the GM rent, and the deadweight loss of the monopoly would range between 15% and 30% of that rent. The remaining rent for farmers may be too small to outweigh possible producer price discounts resulting from the costs of segregating GM and non‐GM oilseed rape along the supply chain.  相似文献   
118.
Agroecology has become a powerful alternative paradigm for rural development. In contrast to conventional approaches, this paradigm shifts the emphasis from technology and markets to local knowledge, social justice and food sovereignty, to overcome rural poverty and environmental degradation. However, the spread of this approach faces several obstacles. This paper deals with one of these obstacles: the ‘preference’ of smallholders for industrial farming. We specifically analyse the widespread uptake up of oil palm by smallholders in Chiapas. Contrary to agro‐ecological assumptions, oil palm proved favourable to smallholders in Chiapas because of historical and contemporary state–peasant relations and the advantageous economic circumstances within the oil palm sector. Based on this research, we identify four challenges for agroecology: (i) the existence of contradictory interests within the peasantry as a result of social differentiation; (ii) the role of the state in making conventional development models relatively favourable to smallholders; (iii) the prevalence of modernization ideologies in many rural areas; and (iv) the need for this paradigm to acknowledge smallholders' agency also when engaged in industrial farming. These challenges need to be tackled for agroecology to offer viable alternatives in a context of agro‐industrialization.  相似文献   
119.
This study analyses the economics of conservation tillage (CT) with respect to its effect on maize yield and chemical fertiliser, herbicide, and female and male labour demand. We estimate production and input demand functions using seemingly unrelated regressions on plot‐level cross‐sectional farm household data collected in the north‐west of Ethiopia. A two‐step control function is applied to address potential endogeneity bias due to the inclusion of the CT adoption decision as an explanatory variable. Our results show that CT increases maize yield and chemical fertiliser demand. Additionally, the results show that the adoption of CT reduces female and male labour required for crop production. However, this is achieved through the increased use of herbicides, which might have an undesirable health and environmental effects.  相似文献   
120.
This article focuses on the way greenfield foreign direct investment (FDI) in different sectors is influenced by locational characteristics and explores the role of policy in attracting and retaining foreign investment. We contribute to the literature by empirically investigating the investment motivations of multinational companies in the software and information technology (IT) and financial services sectors in Ireland and those locational factors that contribute to the retention of FDI. The methodology used in this research is of a qualitative nature, and an exploratory deductive approach is adopted in order to gain an understanding of firms’ internationalization decisions and motivations. The data demonstrate that companies in the two sectors follow different investment motivations. Firms in the software and IT sector entered Ireland primarily because of the availability of a high‐quality workforce, whereas firms in the financial services sector entered Ireland following the deregulation of markets and the subsequent ease of doing business. The article builds on these findings to develop policy recommendations. © 2017 Wiley Periodicals, Inc.  相似文献   
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