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1.
A slowdown in the rate of agricultural productivity growth is thought by many observers to be contributing to the recent rise in agricultural prices. In this article I decompose sources of output growth in global agriculture into aggregate input and total factor productivity (TFP) components and examine whether productivity growth slowed substantially in the years leading up to the recent rise in commodity prices. Contrary to widely held perceptions, I find no evidence of a general slowdown in sector‐wide agricultural TFP, at least through 2006. If anything, the growth rate in agricultural TFP accelerated in recent decades. However, the results do show a slowdown in the growth of agricultural investment. Accelerating TFP growth largely offset decelerating input growth to keep the real output of global agriculture growing at about 2% per year since the 1960s. Regionally, however, agricultural productivity performance has been uneven. These findings have important implications for the appropriate supply‐side policy response to the current agricultural price crisis.  相似文献   

2.
Aquaculture is one of the fastest growing food‐producing sectors, and its share in global seafood production is rising significantly compared with capture fisheries. This transforms seafood production practices while allowing capital to expand to new marine commodity frontiers. Building on the conceptualization of aquaculture as a new frontier for capture fisheries, the article aims to uncover how commodity frontiers expand within the intensive marine aquaculture sector and shape the transformation of seafood production by focusing on its recent growth in Turkey. It analyses this transformation based on 22 in‐depth interviews with key social actors in Turkey, as well as a review of sector and state reports and the relevant legislations of Turkey and the European Union, and argues that the three‐pronged horizontal, vertical, and taxonomic expansion already observed in industrial capture fisheries has similarly taken place in intensive marine aquaculture through the commodity widening, deepening, and marketing strategies employed by aquaculture firms.  相似文献   

3.
The efficient market hypothesis, where asset prices follow a random walk and incorporate all relevant information, is often invoked in financial economics. There is some evidence however to suggest that some asset prices do not follow random walks but display long‐range dependence. Such systematic behavior of past returns is of interest to traders. This article examines long‐range dependence in wheat futures prices using rescaled range analysis and the Hurst exponent. Since this estimate is biased when long‐range dependence is absent and its distribution is unknown, a Monte Carlo simulation approach is proposed. Results show that wheat futures prices show no evidence of long‐range dependence and there are no profitable trading rules.  相似文献   

4.
Much of the public discussion of the food price crisis has focused on the sharply increased use of food commodities for biofuel production, framing debate in simple food versus fuel terms. Reality is more complex. Multiple forces drove food prices to high levels and, according to findings we report in this article, these forces will sustain high prices over the medium term. We also find that the distinction between high world prices for food commodities and the consumer costs of food is an important one to make. Food consumers do not buy raw food commodities at international prices. The degree to which the price of traded food commodities and the price of food are related depends on a long list of factors, most of which operate to dampen price transmission. In the search for appropriate policy response, it is essential to measure consumer effects correctly and to apportion properly the causes of current high prices.  相似文献   

5.
Some producers, policy makers, and researchers claim that packers influence cash prices through contracts tied to futures prices. This paper provides a theoretical and empirical study on the price effects of contract-pricing terms linked to futures price and the related formula pricing terms linked to a cash price. We show that contract-pricing terms tied to a cattle futures price can theoretically be used to reduce the cash price. Furthermore, the model demonstrates that such tied-to-a-futures-price contract-pricing clauses and the related tied-to-a-cash-price formula pricing clauses can be substitutable tools for packers to depress the cash cattle price. Nevertheless, although empirical results are consistent with the predictions of the theoretical model they show that while such manipulations may occur, their market power impact appears quite small.  相似文献   

6.
We assess the effects of the dramatic rise in agricultural commodity prices during 2007–2008 on income dynamics and poverty among rural households in Bangladesh. A unique panel data set allows us to put the effects of recent events in the context of long‐run trends in income and poverty. We use data from a nationally representative longitudinal survey of rural households in Bangladesh collected in four waves in 1988, 2000, 2004, and 2008. Nargis and Hossain (Nargis, N., Hossain, M., 2006. Income dynamics and pathways out of rural poverty in Bangladesh, 1988–2004. Agric. Econ. 35, 425–435) analysed income dynamics and poverty incidence for the first three waves, finding a declining trend in both the incidence and severity of poverty, aided in particular by human capital development and off‐farm employment opportunities. We update and extend the analysis to include data collected in 2008, at the height of a spike in agricultural prices. We find that the price of a balanced food basket increased by more than 50% during 2000–2008, while household income rose only 15%. As a result the incidence and severity of rural poverty in Bangladesh sunk to pre‐2000 levels during 2004–2008. Thus, the price spikes in 2007–2008 helped push an additional 13 million people into poverty in rural Bangladesh. Moreover, we find that the determinants of poverty have not been time‐invariant. In particular, agricultural production, which had previously been associated with a higher incidence of poverty, served as a hedge against higher food prices during 2004–2008.  相似文献   

7.
There exists a large literature on price transmission in agro‐food sectors. However, a great majority of empirical studies focus on the existence of asymmetry and, by and large, do not investigate the reason for its presence or absence. This is in sharp contrast to the theoretical literature that provides a number of explanations of why we should expect (a)symmetry. In response, this paper investigates the reasons for asymmetric price transmission in the agro‐food chain, using meta‐analysis of existing studies. Our focus is on the organizational and institutional characteristics of the agro‐food supply chain. Our findings suggest that asymmetric price transmission in farm–retail relationships is more likely to occur in sectors/countries with more fragmented farm structure, higher governmental support and more restrictive regulations on price controls in the retail sector. On the other hand, more restrictive regulations on entry barriers in the retail sector and the relative importance of the sector tend to promote symmetric farm–retail price transmission. The latter is also more likely in the presence of a strong processing industry.  相似文献   

8.
This paper applies a convention theory (CT) approach to the analysis of labour management systems in African large‐scale farming. The reconstruction of previous analyses of high‐value crop production on large‐scale farms in Africa in terms of CT suggests that, since 1980–95, labour management has moved from a ‘domestic’ to a ‘market’ system. However, data collected by the authors from a sample of 11 large‐scale rose farms in Kenya in 2011 (covering around 20% of national output) points to the adoption of systems that, in CT terms, combine ‘industrial’ and ‘civic’ elements. The paper concludes by suggesting a series of hypotheses that might explain this trend.  相似文献   

9.
This study presents evidence of profound farm‐level transformation in parts of sub‐Saharan Africa, identifies major sources of dynamism in the sector, and proposes an updated typology of farms that reflects the evolving nature of African agriculture. Repeat waves of national survey data are used to examine changes in crop production and marketed output by farm size. Between the first and most recent surveys (generally covering 6 to 10 years), the share of national marketed crop output value accounted for by medium‐scale farms rose in Zambia from 23% to 42%, in Tanzania from 17% to 36%, and in Nigeria from 7% to 18%. The share of land under medium‐scale farms is not rising in densely populated countries such as Kenya, Uganda, and Rwanda, where land scarcity is impeding the pace of medium‐scale farm acquisitions. Medium‐scale farmers are a diverse group, reflecting distinct entry pathways into agriculture, encouraged by the rapid development of land rental, purchase, and long‐term lease markets. The rise of medium‐scale farms is affecting the region in diverse ways that are difficult to generalize. Findings indicate that these farms can be a dynamic driver of agricultural transformation but this does not reduce the importance of maintaining a clear commitment to supporting smallholder farms. Strengthening land tenure security of local rural people to maintain land rights and support productivity investments by smallholder households remains crucial.  相似文献   

10.
This study revisits the issue of long-term price convergence of rice export prices for India, Pakistan, Thailand, Uruguay, the United States, and Vietnam using a two-stage pairwise unit root testing approach. To deduce evidence or lack of proof of convergence in price series, we also examine convergence using sigma and beta convergence specified in both unconditional and conditional frameworks. The methodology used is driven by the need to address three key concerns: (i) the likelihood of finding stationary price differentials, (ii) the magnitude of these differentials, and (iii) their speed of adjustment. To evaluate these concerns, we use monthly data for 18 price series drawn from these six countries from September 2011 to February 2021. The evidence points to a lack of international convergence. This gives rise to the possibility that a shield from a general downward export price trend is already in place for some exporters. Furthermore, we find that the likelihood of convergence is greater between pairs of price series that are characterized as high quality or having the same country of origin or having similar market share. Evidence also suggests that a converged pairing is more likely to have a smaller price differential if both price series are for low-quality rice.  相似文献   

11.
Trade-offs arise between spatial dependence and choice of functional form in agricultural land price hedonic models. We discuss these trade-offs and how they can create spurious spatial dependence. Using a land sales dataset with apparent spatial dependence, we implement a semiparametric approach avoiding potential problems with the functional form. The results show that in addition to being nonlinear, the impacts are also characterized by significance thresholds that are difficult to capture in a parametric model. More importantly, we fail to detect any spatial dependence demonstrating that inappropriate functional form can indeed be responsible for finding spatial dependence in hedonic models.  相似文献   

12.
Information asymmetry exists in virtually every insurance setting. The institutional arrangement of hog insurance in China offers a unique opportunity to investigate the farmer's behavior of under‐reporting the actual number of finished hogs on one hand, and the insurer's efficiency in determining the actual numbers on the other. Using data on 444 hog operators synchronized from farm production survey and insurance records, results showed that farmers report on average 11.5% fewer hogs to the insurance company. The level of under‐reporting is positively associated with the size of operation. Farmers with longer farming experience and more conservative risk attitude report more accurately. The under‐report behavior is also partially attributed to a farmer's limited capacity of accurate estimation. Due to information barrier, the insurance company is only able to recover 18.6% of the under‐report at the indemnity payment stage. Results are robust after controlling for potential sample selection problems. It is suggested that technical supports, public programs and premium incentive designs in repeated insurance should be considered to promote more accurate reports.  相似文献   

13.
We seek to design and implement a WTP elicitation instrument closely resembling an actual grocery shopping experience. An incentive-compatible choice experiment is used to elicit values for a non-GM attribute and a country-of-origin attribute of Canola oil. The choice context is varied to assess whether revealed-preference choice experiments are affected by choice variety. A median premium for non-GM Canola oil is found to approximate C$0.45 or C$0.62/liter according to the choice variety context; different country-of-origin effects are also found as choice context varies. Hypotheses as to why these significant effects of choice contexts occur are suggested.
Nous cherchons à concevoir et à mettre en application un instrument de révélation de la VDP qui ressemble étroitement aux choix que fait un consommateur lorsqu'il effectue son marché. Nous avons utilisé une méthode expérimentale compatible avec les incitations des participants afin de découvrir la valeur accordée à deux caractéristiques de l'huile de canola: non génétiquement modifiée et étiquetée selon le pays d'origine. La liste des choix est variée afin d'évaluer si les préférences révélées sont influencées par la gamme de choix. La prime médiane de l'huile de canola non génétiquement modifiée est d'environ 0,45 $CAN ou 0,62 $CAN le litre selon les choix proposés. Différents pays d'origine figurent aussi dans cette liste de choix. Nous avons formulé des hypothèses quant aux raisons pour lesquelles la gamme de choix a des effets importants.  相似文献   

14.
Human behaviors are driven by implicit and explicit motives. Psychologists have developed two main tools, namely time pressure and cognitive load, to disentangle the two motives. This implies values of willingness to pay (WTP) may be sensitive to time pressure and cognitive load levels in practice. An experiment with 233 students was conducted in China to study the willingness to pay for organic food with consideration of different time pressures and cognitive load levels. Results show that (1) increasing cognitive load could significantly reduce consumers’ WTP for organic food; and (2) time pressure does not have a significant impact on WTP values. Such results suggest researchers should be particularly cautious about the cognitive load situations of respondents during a WTP survey.  相似文献   

15.
The principal concern of this article is the relative importance of input mix as a source of inefficiency. Emphasis in efficiency analysis studies in agricultural production has historically focused on technical inefficiency as a single concept until methodological advances enabled it to be decomposed into pure technical inefficiency and scale inefficiency. But, this advance was insufficient to identify what we consider to be the major source of inefficiency in agricultural production, namely mix inefficiency. We consider that farm enterprises may be particularly susceptible to input mix inefficiency because of restrictions on movement around the frontier isoquant; delays in the adoption of improved technologies embodied in new vintages of production processes; risk as a source of friction in input allocation decisions; and the potential for inconsistency in simultaneously attempting to reach points of allocative efficiency and mix efficiency in input use. We use non‐parametric methods to calculate a Hicks–Moorsteen productivity index using panel data for a sample of specialised pig producers in England and Wales. This index is then decomposed into measures of technology, technical efficiency, scale efficiency and mix efficiency for an input orientation. Results of the analysis show that the estimated mean mix inefficiency (0.736) was substantially larger than mean technical inefficiency (0.975) and mean scale inefficiency (0.957) over the study period.  相似文献   

16.
17.
Summary

This paper is concerned with explaining the relationship between land prices and subdivision activity in Madina, Saudi Arabia. This article is not concerned with the effect of land prices on individual landowners, but rather on the supply of land in general. First it is necessary to explain the increase in land prices and why they have risen in real terms over time, what are the periods of growth and decline and what effects have they had on the supply of land for subdivision. This paper then explains the geographical variations in land prices and their influence on the distribution of land subdivision throughout the Madina area, especially in inner city areas and suburban areas.  相似文献   

18.
Different economic valuation methodologies can be used to value the non‐market benefits of an agri‐environmental scheme. In particular, the non‐market value can be examined by assessing the public’s willingness to pay for the policy outputs as a whole or by modelling the preferences of society for the component attributes of the rural landscape that result from the implementation of the policy. In this article we examine whether the welfare values estimated for an agri‐environmental policy are significantly different between an holistic valuation methodology (using contingent valuation) and an attribute‐based valuation methodology (choice experiment). It is argued that the valuation methodology chosen should be based on whether or not the overall objective is the valuation of the agri‐environment policy package in its entirety or the valuation of each of the policy’s distinct environmental outputs.  相似文献   

19.
20.
Some previous researchers have argued that trading strategies based on calendar spread time series momentum (STSM) can deliver significant returns (Szymanowska et al. 2014; Boons and Prado 2019), which, if true, is at odds with the efficient market hypothesis. These arguments however, do not exclude the unrealisable futures contract roll yield and are also affected by other empirical and statistical issues that may lead to misleading results. With more than 30 years of data, we investigate STSM in 22 US commodity futures markets. First, we assess whether past spread returns can predict future returns, a necessary condition for the existence of momentum. We find predictability to be very weak after correcting for the issues affecting prior research. Second, we implement STSM-based investment strategies. We compare STSM profits for individual markets and portfolios to profits generated by a simple long-only benchmark strategy that does not require any predictability. STSM does not generate returns statistically different from the benchmark trading strategy, with both strategies generating very low or negative returns. For the momentum to outperform the benchmark strategy, predictability should be three times larger than observed from real data, but would entail substantial downside risk. In sum, the empirical evidence indicates that returns from STSM-type strategies are illusive for the commodities and period studied. Our results strongly suggest that inclusion of unrealisable roll yield generates the illusion of profitable STSM trading strategies in previous research.  相似文献   

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