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1.
A copula approach to censored system estimation is proposed. The quasi‐maximum likelihood estimator departs from the multivariate normal error distribution predominantly used in existing estimators and resolves the computational difficulty with multiple probability integrals in high‐dimensional censored systems. An application to individual meat consumption demonstrates that the procedure produces very different empirical estimates from existing Gaussian full‐information and quasi‐maximum likelihood estimates.  相似文献   

2.
This study uses local maximum likelihood (LML) methods recently proposed by Kumbhakar et al. (2007) to assess the technical efficiency of arable crop Kansas farms. LML techniques overcome the most relevant limitations associated to mainstream parametric stochastic and nonparametric frontier models. LML allows deriving farm‐level frontier parameter estimates. The relevance of using localized estimates is evidenced by the observed heterogeneity in production technologies. Technical efficiency scores derived from the LML approach [0.905] are higher than those of the DEA model under CRS [0.808] and SFA [0.804] and close to DEA‐VRS [0.917] ratings. Deriving reliable information about farm efficiency performance is relevant to identify inefficient farms and define adequate policy and management strategies. The use of refined methods has thus important implications.  相似文献   

3.
The paper jointly evaluates the determinants of switching to modern rice and its productivity while allowing for production inefficiency at the level of individual producers. Model diagnostics reveal that serious selection bias exists, justifying the use of a sample selection framework in stochastic frontier models. Results revealed that modern variety selection decisions are influenced positively by the availability of irrigation and gross return from rice and negatively by a rise in the relative wage of labour. Adoption of modern rice is higher in underdeveloped regions. Seasonality and geography/location does matter in adoption decisions. Stochastic production frontier results reveal that land, labour and irrigation are the significant determinants of modern rice productivity. Decreasing returns to scale prevail in modern rice production. The mean level of technical efficiency (MTE) is estimated at 0.82. Results also demonstrate that the conventional stochastic frontier model significantly overestimates inefficiency by three points (MTE = 0.79). Policy implications include measures to increase access to irrigation, tenurial reform and keeping rice prices high to boost farm returns and offset the impact of a rise in the labour wage which will synergistically increase the adoption of modern rice as well as farm productivity.  相似文献   

4.
English and Welsh farm‐level survey data are employed to estimate stochastic frontier production functions for eight different farm types (cereal, dairy, sheep, beef, poultry, pigs, general cropping and mixed) for the period 1982 to 2002. Differences in the relative efficiency of farms are explored by the simultaneous estimation of a model of technical inefficiency effects. The analysis shows that, generally, farms of all types are relatively efficient with a large proportion of farms operating close to the production frontier. However, whilst the frontier farms of all types are becoming more efficient through time because of technical change, it is also the case that the efficiency of the average farm for most farm types is increasing at a slower rate. In addition, annual mean levels of efficiency for most farm types have declined between 1982 and 2002. The factors that consistently appear to have a statistically significant effect on differences in efficiency between farms are: farm or herd size, farm debt ratios, farmer age, levels of specialisation and ownership status.  相似文献   

5.
The concept of eco‐efficiency is becoming increasingly popular as a tool to capture economic and environmental aspects of agricultural production. The literature to date has exclusively used the Data Envelopment Analysis (DEA) approach to measure producers’ eco‐efficiency. We show that it can also be estimated using a Stochastic Frontier Analysis (SFA) approach. Our approach not only allows controlling for random noise in the data but also permits an analysis of the potential substitutability between environmental pressures. We provide an empirical application of our model to data on a sample of Spanish dairy farms.  相似文献   

6.
In parametric efficiency studies, two alternative approaches exist to provide an estimate of the long‐run efficiency of firms: the dynamic stochastic frontier model and the generalised true random‐effects model. We extend the former in order to allow for heterogeneity in the long‐run technical efficiency of firms. This model is based on potential differences in firm‐specific characteristics and in firms’ inefficiency persistence. The model is applied to an unbalanced micro‐panel of German dairy farms over the period 1999 to 2009. Estimation of long‐run technical efficiency and inefficiency persistence is based on an output distance function representation of the production technology and estimated in a Bayesian framework. The results suggest that heterogeneity in long‐run technical efficiency of farms is mostly attributed to discrepancies in farm‐specific factors rather than differences in farms’ inefficiency persistence. Farm size is positively related to long‐run technical efficiency while subsidies exert a negative effect on the long‐run technical efficiency of farms. Inefficiency persistence is found to be very high, but heterogeneity in this persistence is low.  相似文献   

7.
The importance of the agricultural sector in the economic development process is well known. Improvements in agricultural productivity are often found to spill into other areas of a developing economy, potentially improving the standards of living of urban and rural workers alike. Given the importance of this sector, accurate measures of total factor productivity (TFP) across countries can be helpful in identifying conditions, institutions or policies that promote agricultural development. In this article, we estimate TFP growth in agriculture for a panel of 39 sub‐Saharan African countries from 1961 to 2007. We also develop a set of development outcome measures theoretically consistent with strong agricultural performance to serve as external validation of our results. We find that three estimation methods (stochastic frontier, generalised maximum entropy, and Bayesian efficiency) generate relative rankings that are consistent with the development outcome measures, providing external validation of the methods. However, the data envelopment analysis approach performs poorly in this regard.  相似文献   

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10.
In this study, we investigate the impact of an increase in farm households’ off‐farm work on technical efficiency (TE) of U.S. dairies. We present a theoretical framework that implies that an increase in farm household off‐farm work decreases TE. We use two nationally‐representative samples of U.S. dairies (2010 and 2005 Agricultural Resource Management Surveys) and a parametric approach (stochastic frontier analysis) to empirically test the hypothesis. Results are generally consistent with the hypothesis and show that an increase in off‐farm work by the farm household is associated with a significant decrease in TE. In addition, results show that there is a statistically significant difference in TE between small, medium, and large farms. Small farms are associated with significantly higher off‐farm work and have lower TE than large farms, which implies that less off‐farm work by households with larger farms is at least partially responsible for the evidence of economies of scale in the U.S. dairy industry.  相似文献   

11.
We investigate the relationship between EU Common Agricultural Policy environmental payments, and dairy and beef farm level competitiveness and environmental performance. We use an Irish panel of farm level financial data for the years 2000–2017 and apply stochastic frontier analysis. Our estimates identify a positive relationship between technical efficiency and the Green, Low-Carbon, Agri-Environment Scheme for dairy farms, in contrast with the negative relation identified for previous payments of this kind such as the Rural Environment Protection Scheme for both beef and dairy. We then simulate increases in the first type of environmental payments financed through reductions in decoupled payments. We use alternative scenarios for payment redistribution such as flat allocation, allocation to farms with low stocking rates or proportional reallocation of payments. We find that under the second scenario, marginal environmental gains can potentially be achieved for dairy farms. For beef farms, the proportional allocation performs best regarding environmental gains. We also find that under this scenario, the impacts on income inequality can be smoothed for both farm types.  相似文献   

12.
This article investigates the impact of environmental production conditions on smallholder farmers’ technical efficiency in Ethiopia for wheat, maize, and sorghum farming. We use a household panel data set with annual and cropping season environmental production conditions to estimate the technical efficiency scores. The results show that including environmental production conditions in the stochastic frontier has a significant impact on farmers’ technical efficiency scores. Technical efficiency scores improve when environmental production conditions are incorporated in the stochastic frontier. Thus, accounting for environmental production conditions reduces the inefficiencies that otherwise may be attributed to the characteristics of smallholder farmers.  相似文献   

13.
There is an increasing policy interest in pesticide taxation schemes as a measure to reduce harmful effects of pesticide use. The effectiveness of such tax depends, however, on the price elasticity of demand for pesticides. Moreover, information on these demand elasticities and their determinants is of crucial relevance for policy‐making and normative modeling approaches. In this article, we present a meta‐analysis based on studies that have estimated pesticide demand elasticities in Europe and North America. Our meta‐analysis reveals that the own‐price elasticities of demand for pesticides are, with a median of ?0.28, significantly smaller than zero, but also significantly larger than ?1, i.e. to be inelastic. We find that the demand for pesticides for special crops is less elastic than that for arable and grassland. In addition, the demand for herbicides is more elastic than for other pesticides. Studies that consider only short‐term horizons and little flexibility for farmers to adjust to price changes generate significantly less elastic pesticide demands. The results also indicate that more recent studies identify lower pesticide price elasticities of demand. Furthermore, we find that peer‐reviewed studies tend to find more inelastic results compared to grey literature.  相似文献   

14.
We employ a discrete choice experiment to elicit demand and supply side preferences for insurance‐linked credit, a promising market‐based tool for managing agricultural weather risks and providing access to credit for farmers. We estimate preference heterogeneity using primary data from smallholder farmers and managers of lenders/insurers combined with household socio‐economic survey data in Kenya. We analyse the choice data using maximum simulated likelihood and Hierarchical Bayes estimation of a mixed logit model. Although there are some similarities, we find that there is conflicting demand and supply side preferences for credit terms, collateral requirements, and loan use flexibility. We also analyse willingness to buy and willingness to offer for farmers and suppliers, respectively, for the risk premium for different attributes and their levels. Identifying the preferred attributes and levels for both farmers and financial institutions can guide optimal packaging of insurance and credit providing market participation and adoption motivation for insurance‐bundled credit product.  相似文献   

15.
The paper jointly evaluates the determinants of switching to Jasmine rice and its productivity while allowing for production inefficiency at the level of individual producers. Model diagnostics reveal that serious selection bias exists, justifying use of a sample selection framework in stochastic frontier models. Results from the probit variety selection equation reveal that gross return (mainly powered by significantly higher Jasmine rice price), access to irrigation and education are the important determinants of choosing Jasmine rice. Results from the stochastic production frontier reveal that land, irrigation and fertilisers are the significant determinants of Jasmine rice productivity. Significantly lower productivity in Phitsanulok and Tung Gula Rong Hai provinces demonstrate the influence of biophysical and environmental factors on productivity performance. The mean level of technical efficiency is estimated at 0.63 suggesting that 59% [(100 ? 63)/63] of the productivity is lost due to technical inefficiency. Policy implications include measures to keep Jasmine rice price high, increase access to irrigation and fertiliser availability, as well as investment in education targeted to farm households which will synergistically increase adoption of Jasmine rice as well as farm productivity.  相似文献   

16.
Two of the experimental methods used to estimate willingness‐to‐pay (WTP) for a non‐market good, the Becker‐DeGroot‐Marschak (BDM) mechanism and the non‐hypothetical choice experiment (nHCE) often lead to significantly different WTP estimates, complicating the choice between the methods. In Zambia the same group of researchers used both techniques to evaluate WTP for orange maize, which provides more vitamin A than other varieties. This provided an opportunity to analyse the sources of the difference. In the BDM experiment, one group of respondents was provided with more training opportunities than the other, and made higher bids. Accounting for lexicographic behaviour in the nHCE reduced the estimated WTP. These two design factors together resulted in a decrease in the WTP difference for orange maize (1,279–632 ZMK) although the difference remains statistically significant. More training was also shown to eliminate the effects of different orders in which maize varieties were presented.  相似文献   

17.
We propose that an options‐based approach is a superior alternative to the traditional cost‐of‐carry method to model both the behaviour of convenience yields and the commodity price responses to changes in inventory levels. This approach is shown to be more robust and avoids the simplifying assumptions embedded in cost‐of‐carry valuation which fully accounts for the non‐negativity constraint on inventory. Unlike the cost‐of‐carry approach, the options‐based approach does not treat the convenience yield as an exogenous factor. This offers a more natural measure of implied convenience yields in commodity trading strategies. We test the relationship between convenience yields and inventory levels for a number of liquidly traded base metals using both methods. Our results show that the relationship between convenience yields and inventory levels is strongly defined under the options‐based approach in line with market beliefs. This result is consistent with other studies that have used the options‐based approach in other nonmetals commodity markets.  相似文献   

18.
The banana prawn component of Australia's Northern Prawn Fishery (NPF) is currently managed through the use of annually updated trigger catch rates as a means of achieving maximum economic yield (MEY) in the fishery, taking into account the estimated price and cost components for that season. The estimation of these target catch rates is based on the assumption of relative homogeneity of the fleet in terms of efficiency, productivity and cost structure. In this study, these assumptions are examined through the estimation of a stochastic production frontier. While technical efficiency varies between vessels, average efficiency is relatively constant over the fishing season. However, average productivity of the fleet increases, with smaller vessels (in terms of engine power) exiting the fishery earlier. This would likely increase the average cost of fishing towards the end of the season, with implications for setting the target catch rate. Based on a standard assumption as to the relationship between costs and vessel size, we find that the MEY target catch rates are most likely currently underestimated. However, the implementation of a precautionary minimum catch rate (which is above the MEY target catch rates for recent years) has maintained the fishery at a profitable level.  相似文献   

19.
Drawing upon the concept of ‘accumulation by dispossession’, this paper analyses the expansion of agrarian capital in Argentina. A case study illustrates the social and environmental impacts of the expansion of agribusiness in central Argentina and the social struggle – both rural and urban – that has arisen to resist this process. Although government policies after the 2001 crisis differ in many ways from those of the 1990s, current agrarian policies are not significantly distinct from those followed during the pre‐crisis neoliberal period. Rather than ‘post‐neoliberal’, the new model could thus be better described as ‘neo‐extractivist’. With the connivance of the state, agribusiness is producing the largest‐ever transformation of natural capital into economic capital in the history of the region. Moreover, the latest policy developments suggest that Argentina is on the threshold of a new and deeper stage of agrarian capital expansion and wealth concentration, this time operating at a much larger scale.  相似文献   

20.
Employing an endogenous switching regression model, we investigate the drivers underlying the adaptations made by farm households and their impacts on crop net incomes for adopters and nonadopters, based on a large panel survey data set across the major grain‐producing provinces in China. The results show that: (i) access to public climate information and technical or physical support increases the likelihood that farmers adapt to climate change by undertaking irrigation and/or drainage measures; and (ii) decisions to adapt increased crop yield, but they did not significantly increase crop profit margins. This point appears to have been ignored by previous studies. Based on these new empirical results, the paper suggests that government should continue to provide climate information and various types of supports to improve farmers’ adaptation abilities and help to reduce the levels of factor input by, for example, substituting organic for chemical fertiliser inputs. Such government‐led policies should be supported alongside the implementation of domestic agricultural supply‐side reform.  相似文献   

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