Farmers' Subjective Valuation of Subsistence Crops: The Case of Traditional Maize in Mexico

Shadow prices guide farmers' resource allocations, but for subsistence farmers who grow traditional crops they may bear little relationship with market prices. We theoretically derive shadow prices for a subsistence crop with nonmarket value, then estimate shadow prices of maize using data from a nationally representative survey of rural households in Mexico. Shadow prices are significantly higher than market prices for traditional but not improved maize varieties. They are particularly high in the indigenous areas of southern and southeastern Mexico, indicating large  de facto  incentives to maintain traditional varieties there.     

Welfare effects of maize technologies in marginal and high potential regions of Kenya

This paper describes the findings of a study that used a multi‐market model to assess the potential impact of improved maize technologies on the welfare of various types of rural and urban households in Kenya. The modelling results indicate that technologies developed for high potential regions are likely to have more profound aggregate impacts on maize production and lead to greater reductions in import demand (if prices are controlled) or maize prices (if maize prices are flexible). Technology adoption in high potential regions is likely to have substantially greater positive impacts on aggregate real incomes, but inferior income distributional outcomes compared to technology adoption in marginal regions.     

Impacts of Market Reform on Spatial Volatility of Maize Prices in Tanzania

Maize is one of the major staples and cash crops for many Tanzanians. Excessive volatility of maize prices destabilises farm income in maize‐growing regions and is likely to jeopardise nutrition and investment in many poor rural communities. This study investigates whether market reform policies in Tanzania have increased the volatility of maize prices, and identifies regional characteristics that can be attributed to the spatial price volatility. To achieve the objectives, an autoregressive conditional heteroskedasticity in mean (ARCH‐M) model is developed and estimated in this study. Results show that the reforms have increased farm‐gate prices and overall price volatility. Maize prices are lower in surplus and less developed regions than those in deficit and developed regions. Results also show that the developed and maize‐deficit regions, and regions bordering other countries have experienced less volatile prices than less developed, maize‐surplus and non‐bordering regions. Our findings indicate that investments in communication and transportation infrastructures from government and donor countries are likely to increase inter‐regional and international trade, thereby reducing the spatial price volatility in Tanzanian maize prices in the long run.     

Long‐Run Drift,Co‐Movement and Persistence in Real Wheat and Maize Prices

Trends in real prices for food commodities are both important and controversial. Paying particular attention to issues of methodology, this paper assesses the evidence for a downward drift in the real prices of wheat and maize. It is found that the apparent strength of that evidence depends substantially on whether the time series generating models are taken to be trend‐stationary or difference‐stationary, and on whether allowance is made, through incorporation of dummy variables in the models, for events in one or two extreme years. Once dummy variables are incorporated, we find little evidence against difference‐stationarity. The analysis then proceeds, through tests for cointegration, to the construction of error‐correction models linking the two prices and to the estimation of persistence of shocks in this bivariate framework. The paper presents modest evidence for downward drift in real grain prices of about 1 to 1.5 per cent per annum, shows that wheat and maize prices cointegrate and estimates that direct and cross‐persistence measures take values of less than unity.     

The transmission of world maize price to South African maize market: a threshold cointegration approach

This article seeks to provide an explanation for the relationship between domestic maize price in South Africa and world maize prices in order to evaluate comovement and transmission of world prices to domestic prices in sub‐Sahara African countries. This is done by comparing nested and nonnested models that capture different forms of nonlinearity in the price spread. Adopting a Bayesian approach that allows for comparison of models using Bayes factor, we found that the relationship between South African price and world price for maize indicates the presence of nonlinearity in price transmission with three regimes that is triggered by the price spread in previous period.     

Food price increases and net food importing countries: lessons from the recent past

Recent increases in food and other commodity prices have highlighted concerns that many poor countries are net food importers and higher food prices would worsen their trade balances. In this article, we analyze the changes in food trade balances associated with the 32% increase in food prices from 2000/2001 to 2004/2005. We find a small deterioration in food trade balances of low‐income countries and an improvement in middle‐income countries. The deterioration is most severe for countries in conflict and small island states, so attention should be placed first on these countries and on a few very‐low‐income countries that are also vulnerable. Because low‐income countries as a group had much lower agricultural GDP growth rates than middle‐income countries, the answers to food vulnerability in low‐income countries should probably be addressed within the context of incentives for agricultural production.     

Estimating shadow price for symbiotic nitrogen and technical efficiency for legume‐based conservation agriculture in Malawi

Determining the value of legumes as soil fertility amendments can be challenging, yet this information is required to guide public policy and to incentivise prescribed land‐management practices such as conservation agriculture. We use a directional input distance function (DIDF) to estimate shadow prices for symbiotic nitrogen and the technical efficiency for mixed maize‐legume production systems in Malawi. The shadow prices reflect the trade‐off between fertiliser nitrogen and symbiotic nitrogen required to achieve a given quantity of output. Our results reveal considerable technical inefficiency in the production system. The estimated shadow prices vary across farms and are, on average, higher than the reference price for commercial nitrogen. The results suggest that it would be beneficial to redesign the current price‐support programs that subsidise chemical fertilisers and indirectly crowd‐out organic soil amendments such as legumes.     

国内外玉米价格传导关系影响研究——基于收购政策市场化改革背景

[目的]玉米在国家粮食安全中占有重要地位,是国内外市场联系最为紧密的大宗农产品之一。文章旨在探讨收购政策市场化改革前后,国内外玉米价格传导关系是否发生变化,为政府推进玉米供给侧改革提供理论依据。[方法]该文选取2009—2018年国内外玉米价格周度数据,利用向量误差修正模型和门限向量误差修正模型分别对收购政策市场化改革前后国内外玉米市场间价格传导关系进行实证分析。[结果]长期内,国内外玉米价格存在长期稳定的均衡关系,国际玉米价格对国内玉米价格具有持续稳定的正向传导关系;短期内,收购政策市场化改革前,国内外玉米价格间存在线性调整关系,具体表现为国际玉米价格向国内玉米价格单向传导关系;而收购政策市场化改革后,国内外玉米价格短期非均衡误差调整动态存在门限非对称调整关系,且改革后未来国内玉米价格受到当期国内玉米价格影响较大。[结论]这些结论对推进玉米供给侧改革,维护国内玉米市场的健康有序发展有一定的参考作用。     

Price Transmission in Nigerian Food Security Crop Markets

This paper comprehensively examines price transmission from world, neighbour country, and internal commercial hub markets to Nigerian urban markets, as well as from urban to rural markets within the country, for seven key food security crops (maize, millet, sorghum, rice, cassava, yams and cowpeas). There are three key findings: (i) tradability matters for price transmission, but tradability varies across crops and regions. The strongest international linkages are with neighbouring countries. Rice price transmission is high across all markets, while coarse grain price correspondence is low with world prices but high with neighbour country market prices; (ii) our results imply that local conditions matter for price transmission, and are relatively more important than trade for some crops (e.g. yams, cassava) than others (e.g. imported rice, maize); (iii) larger than expected long‐run price transmission parameters in world and neighbour countries for rice and coarse grains suggest that, in these select markets, there are either large transactions costs or quality premiums that vary systematically with border prices, and/or mark‐ups captured by traders with market power.     

Impacts in Uganda of rising global food prices: the role of diversified staples and limited price transmission

This study assesses the potential impact of rising world food prices on the welfare of Ugandan households. While Uganda experienced sharply higher food prices in 2008, as a landlocked, food‐exporting country the causes of those price changes were mainly regional and indirect rather than directly transmitted from global markets. Using trade volumes, food prices, and household survey data we describe how Uganda, unlike some other countries, is partially shielded from direct impacts of global food price movements. Although the majority of Ugandans are net food buyers, the adverse impact at household‐level of rising global prices is moderated by the relatively large quantity and range of staples consumed that come from home production. Moreover, several of these are not widely traded. Some population groups in Uganda are vulnerable to rising food prices, however, primarily those for whom maize is an important staple, including those dependent upon humanitarian relief and the urban poor. Only a relatively small group of Ugandan households will benefit directly and immediately from rising food prices—the significant net sellers of food crops constituting between 12% and 27% of the population. In this assessment we do not estimate the level and extent of wider second round effects from these higher prices.     

Smallholder Supply Response to Marketing Board Activities in a Dual Channel Marketing System: The Case of Zambia

In recent years, parastatal grain marketing boards have re‐emerged as important elements of grain markets in eastern and southern Africa, yet little is known about how farmers are responding to their scaled up activities. This article develops a conceptual model of farmers’ production decisions in the context of dual output marketing channels (government and private sector) when output prices at harvest time and the availability of one of the marketing channels are unknown at planting time. It then applies the model to the case of Zambia and uses nationally representative household‐level panel survey data to estimate the effects of the Food Reserve Agency (FRA), the government parastatal maize marketing board, on smallholder crop production and fallow land. The FRA buys maize from smallholders at a pan‐territorial price that typically exceeds market prices in major maize producing areas. Results suggest that increases in the farmgate FRA maize price raise farmer maize price expectations, which induces a supply response. Smallholders respond to an increase in the FRA price by extensifying their maize production. On average, a 1% increase in the FRA price is associated with 0.06% increases in smallholders’ maize area planted and quantity harvested. There is also some evidence that farmers reduce the area of land under fallow in response to FRA incentives but there is no evidence of reductions in the area planted to other crops.     

The effects of NCPB marketing policies on maize market prices in Kenya

The Government of Kenya pursues maize marketing policy objectives through the National Cereals and Produce Board (NCPB), which procures and sells maize at administratively determined prices, and stores maize as a contingency against future shortages. A private sector marketing channel competes with the NCPB. This article estimates the effects of NCPB activities on the historical path of private sector prices in Kenyan maize markets between 1989 and 2004. The analysis is carried out using a reduced form vector autoregression model (VAR) estimated with sparse data and imposing only minimal identification restrictions. Results show that NCPB activities have stabilized maize market prices in Kenya, reduced price levels in the early 1990s, and raised average price levels by roughly 20% between 1995 and 2004. Over the past decade, the price-raising activities of the NCPB have transferred income from urban consumers and a majority of small-scale farm households that are net buyers of maize to a relatively small number of large- and small-scale farmers who are sellers of maize.     

Cropland use,yields, and droughts: spatial data modeling for Burkina Faso and Niger

For countries with recurrent droughts, the design of drought impact mitigation measures could benefit from analyses of determinants of yields and prices of local crops at regional and district level. This study applies dynamic spatial panel data regression models to yields and prices of four major food crops across regions of Burkina Faso and Niger, over sample periods between 1984 and 2006. Results lend support to mainly simultaneous spatial spillovers, particularly for millet and cowpea prices and sorghum yields in Niger, and maize yields in Burkina Faso. After accounting for these effects, most crop yields are found to be weakly price‐responsive, as envisaged by a supply‐side geographical diffusion hypothesis. Seasonal rainfall elasticity estimates suggest that dominant food crops have slight advantage margins in terms of relative resilience to rainfall shortages. However, this result is to be weighed against low millet yields in Niger, and marked drops in sorghum yields during officially declared droughts in Burkina Faso.     

Modeling the Effects of Input Market Reforms on Fertiliser Demand and Maize Production: A Case Study from Kenya

Kenya is one of the few countries in Sub‐Saharan Africa to experience an impressive rise in fertiliser use following a series of input market reforms in the early 1990s. Two major consequences of these reforms were declining fertiliser marketing margins and distances between farmers and fertiliser dealers. We quantify the effects of these changes on commercial fertiliser use and maize production in Kenya by estimating fertiliser demand and maize supply response functions using nationwide household survey data. Our results indicate that between 1997 and 2010, the estimated 27% reduction in real fertiliser prices that can be attributed to falling marketing margins associated with market reforms led to a 36% increase in nitrogen use on maize fields and a 9% increase in maize production resulting from both yield and acreage effects. On the other hand, decreasing distances to fertiliser retailers from the perspective of a given household did not appear to raise fertiliser use or maize supply, although a comparison across households using average distances over the panel indicate that those closer to retailers do apply more fertiliser on their maize fields.     

Consumption Trends of Edible Mushrooms in Developing Countries

Abstract

Mushrooms are an important commodity worldwide. However, a thorough understanding of consumption trends is not yet available. In developing countries, the importance of edible mushrooms within consumer preferences and perceptions has not been studied. We carried out a study (2000-2003) to understand the patterns of mushroom consumption in central Mexico, where most wild/cultivated mushrooms are produced and/or marketed. About one-half (49.4%) of urban consumers bought mushrooms, independently of their social level [fresh or canned: white button mushroom (Agaricus), oyster mushroom (Pleurotus), shiitake (Lentinula). Preferences and perceptions from Mexican consumers depended on the social level. Mushroom prices were considered very or moderately expensive. Mushrooms were markedly more expensive than foods widely consumed. The variation of mushroom prices was a major factor influencing consumption. Basic data to carry out further marketing research are discussed, as well as an integral strategy considering social levels and regions to increase mushroom consumption.     

The linkage between the U.S. ethanol market and developing countries’ maize prices: a panel SVAR analysis

The major expansion of U.S. ethanol production raises concerns about the potential detrimental impacts on developing countries’ agricultural prices, farm income, and food security. To assess the sensitivity of maize prices to ethanol production, this study explores the linkage between the U.S. ethanol market and developing countries’ maize prices. The econometric approach, based on a panel structural vector autoregression model, captures market interdependencies and the likelihood that developing countries’ responses are both heterogeneous and dynamic. The results indicate that the U.S. ethanol market's impacts on maize prices in developing countries are heterogeneous and that coastal countries are more susceptible to U.S. economic shocks. The estimates also suggest that countries more dependent on food imports and/or receiving U.S. food aid are at a higher risk of being affected by such shocks. Overall, the results indicate that those countries with the greatest sensitivity and exposure to global agricultural commodity markets could benefit from domestic policies and international assistance, which reduce their exposure to impacts from the U.S. maize market.     

The effects of the Food Reserve Agency on maize market prices in Zambia

Over the last decade, governments throughout eastern and southern Africa have increasingly used strategic reserves and/or marketing boards to influence grain market outcomes, yet little is known about how these activities are affecting grain markets. This article estimates the effects of the Food Reserve Agency (FRA) on maize market prices in production and consumption regions in Zambia using a vector autoregression model and monthly data from July 1996 through December 2008. In recent years, FRA has become the dominant buyer of smallholder maize in Zambia. Simulations show that FRA activities stabilized market prices throughout the July 1996–December 2008 study period and raised mean prices between July 2003 and December 2008 by 17–19%. The price raising effects of FRA policies have assisted surplus maize producers but adversely affected net buyers of maize in Zambia, namely urban consumers and the majority of the rural poor. The increase in maize price stability is unlikely to have had substantial welfare effects on poor households. In contrast, relatively wealthy producers are likely to have benefited from the higher average and more stable maize prices resulting from FRA policies.     

Are we overestimating the negative impact of higher food prices? Evidence from Ghana

Most studies of the welfare impact of higher food prices adopt Deaton's approach, based on the first‐order effect of prices changes using income and expenditure survey data. This paper explores the impact of higher maize and food prices in Ghana and considers the sensitivity of results to changes in several assumptions. If second‐order effects are included, incorporating household response to price changes, the welfare impact of food price increases is more positive, but only modestly so. However, if we assume that marketing margins are constant in real terms rather than proportional to prices, the welfare impact is substantially more positive. These findings highlight the need for more research on the behavior of marketing margins under volatile prices.     

Testing vertical price transmission for Vietnam's Robusta coffee

Vietnam has undergone market reforms over the last three decades; and as a consequence, the coffee sector has become increasingly market‐driven. The success of the government's liberalisation policies in terms of market efficiency is investigated by examining the transmission of both positive and negative price changes for Robusta coffee between export and farmgate prices. We used a threshold vector error correction model and high‐frequency daily data. The primary result here is that of a symmetric price transmission between export and farm‐level prices. This result holds when tested with weekly price data, derived from the daily data. Farmgate prices respond faster to decreases than increases in export prices when the long‐run deviation exceeds a certain threshold. These price changes are transmitted within several days. This research also confirms the importance of transaction costs, and other price frictions mostly ignored in prior analyses for coffee.     

Productivity and international competitiveness of agriculture in the European Union and the United States

This study looks at international competitiveness of agriculture in the European Union and the United States. The most intuitive concept is that of price competitiveness. We calculate relative prices for 11 member states of the European Union and the United States for the period 1973–2002. We assume that markets are perfectly competitive and in long‐run equilibrium, so that the observed price always equals average total cost, as measured by the cost dual to the production function. This assumption is used in our calculation of relative competitiveness and productivity gaps between the European Union and the United States and in our decomposition of relative price movements between changes in relative input prices and changes in relative productivity levels.