Evaluating price transmission between global agricultural markets and consumer food price indices in the European Union

This paper uses error correction models to evaluate the extent to and speed at which world agricultural commodity price movements affect consumer food prices in the European Union member states. We consider three types of world commodity price indices, each containing different commodities and weighting criteria. Results reveal a long‐run relationship between world agricultural commodity and consumer food prices in over half of the member states. Consumer prices in different member states and categories of member states respond differently to specific world price indices, suggesting that there are disparities in the structure and the efficiency of their food markets. The eurozone founders generally have lower transmission elasticities. This should be taken into account when predicting the impacts of extreme world price volatility and consumer food price rises, prompting governments to pay attention to the most vulnerable households.     

Tracing the evolution of the aggregate U.S. milk supply elasticity using a herd dynamics model

The U.S. dairy sector is characterized by increasing volatility of milk prices, and consolidation in production as evidenced by declining number of dairy farms with an increasingly larger share of milk supplied from a small number of very large farms. Using aggregate national data, we build a mixed‐frequency herd dynamics econometric model of the U.S. milk supply that updates and substantially amends the model first proposed by Chavas and Klemme. We implement a dynamic residual‐based bootstrap technique that can be used in testing for changes in nonmarginal simulated long‐run supply responsiveness, and trace the evolution of long‐run milk supply elasticity from 1975 through 2010. Several papers in the past have suggested that long‐run supply elasticity increases with dairy farm size, which implies that increased importance of large farms would increase aggregate long‐run supply responsiveness. Contrary to this conclusion, we find a declining trend in long‐run supply elasticity from 1975 through 2005. Persistence of such a decline would be a major cause for worry, as ever larger price swings would be needed to equilibrate the market in face of demand shocks. However, we find that milk supply is becoming more responsive since 2005 both to milk and feed price changes. Increasing responsiveness to feed prices further justifies focusing the next generation of the dairy policy instruments on managing dairy profit margins rather than just revenue streams.     

Higher fuel and food prices: impacts and responses for Mozambique

Rising world prices for fuel and food represent a negative terms‐of‐trade shock for Mozambique. The impacts of these price rises are analyzed using various approaches. Detailed price data show that the world price increases are being transmitted to domestic prices. Short‐run net benefit ratio analysis indicates that urban households and households in the southern region are more vulnerable to food price increases. Rural households, particularly in the North and Center, often benefit from being in a net seller position. Longer‐term analysis using a computable general equilibrium (CGE) model of Mozambique indicates that the fuel price shock dominates rising food prices from both macroeconomic and poverty perspectives. Again, negative impacts are larger in urban areas. The importance of agricultural production response in general and export response in particular is highlighted. Policy analysis reveals difficult trade‐offs between short‐run mitigation and long‐run growth. Improved agricultural productivity has powerful positive impacts, but remains difficult to achieve and may not address the immediate impacts of higher prices.     

Cereal price shocks and volatility in sub‐Saharan Africa: what really matters for farmers’ welfare?

The lack of information as well as some misperceptions about the distinction between the welfare consequences of higher versus more volatile cereal prices has limited the effectiveness of policy interventions during the recent food crises in many developing countries. This article proposes an integrated empirical strategy to investigate and compare the different effects of these two phenomena and tests it using nationally representative household survey data from four sub‐Saharan countries. Results show that the negative impacts of a cereal price increase substantially outweigh the effects of price volatility on household welfare across the entire income distribution. The amplitude and the distribution of those effects depend heavily on specific factors, such as: the weight of food consumption over total expenditure; the budget share devoted to cereals; the substitution effect among food groups; and the relative number of net sellers versus net buyers accessing the market. We also show that volatility mainly harms the poorest quintile of the population.     

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.     

Using a functional approach to test trending volatility in the price of Mexican and international agricultural products

In this article, we extend the traditional GARCH(1,1) model by including a functional trend term in the conditional volatility of a time series. We derive the main properties of the model and apply it to all agricultural commodities in the Mexican CPI basket, as well as to the international prices of maize, wheat, swine, poultry, and beef products for three different time periods that implied changes in price regulations and behavior: before the North American Free Trade Agreement (NAFTA; 1987–1993), post‐NAFTA (1994–2005), and commodity supercycle (2006–2014). The proposed model seems to adequately fit the volatility process and, according to heteroscedasticity tests, also outperforms the ARCH(1) and GARCH(1,1) models, some of the most popular approaches used in the literature to analyze price volatility. Our results show that, consistent with anecdotal evidence, price volatility trends increased from the period 1987–1993 to 1994–2005. From 1994–2005 to 2006–2014, trends decreased but the persistence of volatility increased for most products, especially for international commodities. In addition, we identify some agricultural products such as avocado, beans, and chicken that, due to their increasing price volatility trends in the 2006–2014 period, may present a risk for food inflation in the short run.     

Food Price Pass‐Through and the Role of Domestic Margin Services

The recent volatility in international agricultural markets has drawn attention to the impact of rising international agricultural prices and the induced price‐insulating measures on consumer food prices. Analyses based on simulation models on this topic typically ignore the role of domestic margin services. We extend the standard Global Trade Analysis Project (GTAP) model to allow for variations in the share of domestic margin services in consumed food across countries. This approach enables us to differentiate consumer prices from producer prices. Following the extension, the results show that domestic margin services reduce the consumer food price volatility for all countries, especially in high‐income countries, where the share of domestic margin services in final food consumption is higher. The effect of price‐insulating border policies is also reduced in the extended model. We find that our extension of the GTAP model greatly improves simulations of the 2007 surge in international agricultural prices. We validate our extension of the GTAP model by showing that the econometrically estimated food price pass‐through is decreasing with income and thus, is smaller in high‐income countries.     

Inter‐ and intra‐seasonal crop acreage response to international food prices and implications of volatility

Understanding how producers make decisions to allot acreage among crops and how decisions about land use are affected by changes in prices and their volatility is fundamental for predicting the supply of staple crops and, hence, assessing the global food supply situation. This study makes estimations of monthly (i.e., seasonal) versus annual global acreage response models for the world's principal staple food crops: wheat, corn, soybeans, and rice. Primary emphasis is given to the magnitude and speed of the allocation process. Estimation of intra‐annual acreage elasticity is crucial for expected food supply and for input demand, especially in the light of the recent short‐term volatility in food prices. The econometric results indicate that global crop acreage responds to crop prices and price risks, input costs as well as a time trend. Depending on respective crop, short‐run elasticities are about 0.05 to 0.40; price volatility tends to reduce acreage for some of the crops; comparison of the annual and the monthly acreage response elasticities suggests that acreage adjusts seasonally around the globe to new information and expectations. Given the seasonality of agriculture, time is of an essence for acreage response. The analysis indicates that acreage allocation is more sensitive to prices in the northern hemisphere spring than in winter and the response varies across months.     

The impact of OECD biofuels policies on developing countries

OECD countries’ biofuels policies, derived from energy and environmental legislation and activated by high oil prices, were the primary cause of not only the sudden spike in grain and oilseed prices in 2007–2008 but also of the ensuing price volatility. Even though developing countries have a comparative advantage in biofuels production, they were shut out of rich countries’ biofuel markets by trade discriminating biofuels policies. Developing countries would not have been able to take full advantage of the price spike in the short run anyway given the low supply elasticities and the long time required for biofuel production to come online, unlike for corn‐ethanol. The controversy over the right price of food is misplaced and policy makers should instead focus on improving biofuels policies, which like their counterpart agricultural policies in previous decades, have damaged the welfare of developing countries.     

Nonlinearities in the U.S. corn‐ethanol‐oil‐gasoline price system

We use a smooth transition vector error correction model to assess price relationships within the U.S. ethanol industry. Monthly ethanol, corn, oil, and gasoline prices from 1990 to 2008 are used in the analysis. Results indicate the existence of long‐run relationships among the prices analyzed. Strong links between energy and food prices are identified.     

Volatility in Oilseeds and Vegetable Oils Markets: Drivers and Spillovers

Food price volatility has re‐emerged as an important topic of political discussion since the food price crisis of 2007–2008. Different volatility drivers have been identified for different markets in the theoretical and empirical literature. However, there is no comprehensive analysis that considers a large number of potential drivers and investigates their joint effects in a dynamic model of interrelated markets. Our study provides such a volatility analysis for the oilseeds and vegetable oils markets. We use a common GARCH approach and a VAR model to identify volatility drivers and spillover effects. Our results show that exchange rate volatility is very important. However, the hotly debated financialisation of commodity markets is not found to be volatility increasing in our monthly data. Impulse response functions show strong spillover effects. Because many volatility drivers found to be important in other markets have no significant effect in our study, our results suggest that volatility drivers are market specific. This implies that any volatility‐reducing policies need to be designed for the market in question.     

Futures markets and price stabilisation: An analysis of soybeans markets in North America

The objective of this paper was to determine whether the futures markets have a stabilising or destabilising impact on soybean's spot prices in North America. Directed acyclic graphs (DAGs) are used to test for causality between futures prices, spot prices and ending stocks, followed by time series econometric analysis. The DAGs point to the two-way causal link between futures and spot prices and a lack of a causal link between inventory/stocks and spot price volatility. Time series results, including cointegration, vector error correction, impulse response and variance decomposition analysis, indicate a large impact from futures markets on the level and volatility of soybean spot prices in both the short and long run. These results have potentially important implications, as the impact of commodity price volatility is typically asymmetric across different actors. Farmers, for example, unlike speculators, utilise price risk management (PRM) instruments such as futures markets to mitigate price risks and appear to suffer from intensified volatility precisely because of their use of these instruments. Therefore, additional policies to cope with commodity price volatility, such as direct price controls or mitigation of consequences, can have critical stabilising functions supporting farmers' welfare and regional (rural) development.     

A Two Factor Model for Water Prices and Its Implications for Evaluating Real Options and Other Water Price Derivatives

Single stochastic water price processes may not be able to capture relevant impacts of temporary shocks and permanent shocks on water prices. In this paper, a two factor modeling framework is proposed to incorporate the impacts of these shocks. The model is used to analyze the optimal investment rule when such a composite water price process applies. It is found that ignoring the information on long‐run water price, as in one factor models, can cause an exercise of the real option too early, and result in even negative investment net present value when long‐run water price is low. Giving rise to closed form solutions of European option values, the modeling framework also contributes to facilitate the imminent emergence of water price derivatives in water markets.     

Destabilizing role of futures markets on North American hard red spring wheat spot prices

The objective of the paper is to determine if the futures prices of hard red spring wheat (HRSW) have stabilizing or destabilizing impact on spot HRSW price in North America. Several important results emerge from thorough empirical analysis. First, both Granger causality tests and directed acyclic graph algorithms (DAGs) point to two-way causality between futures and spot HRSW prices and thus endogeneity in both prices formation. To the contrary, both procedures suggest that ending stocks are exogenous to spot and futures HRSW prices. Both vector error correction model and impulse response functions point to a large and long-lasting impact of a shock to futures price on spot price level. Finally, variance decomposition analysis indicates that futures prices are responsible for the bulk of spot price volatility in both short and long run. Our result is consistent with those of theoretical models suggesting that when production (supply side) is the dominant disturbance, spot price is destabilized in both the short and the long run by futures prices. An important implication of this research is the need for alternative market mechanisms or alternative farm policy measures that would mitigate price risk and ensure sustainable farming of American HRSW farmers.     

Cross country maize market linkages in Africa: integration and price transmission across local and global markets

In order to study short‐run price shock propagation, we model twenty seven Sub‐Saharan Africa (SSA) domestic maize markets within a Global Vector Autoregression framework. The main purpose is to fully embed multilateral trade flows as a way to better structure local price transmission dynamics and interdependencies, and get a more comprehensive picture of food price shocks propagation. We found significant between‐country market contagion and prompt regional price shock propagation when trade connection exists. Yet, the integration of SSA domestic maize markets within the continent and with global markets remains generally weak. Furthermore, under regular market conditions, most local price series appear to be more responsive to regional neighbors than to global shocks.     

Testing for spatial market integration: evidence for Colombia using a pairwise approach

We examine the extent of spatial market integration in Colombia using consumer price index data for 153 consumer goods in 13 cities. An econometric analysis of the time‐series properties of all the possible city price differentials reveals that market integration tends to occur more frequently in unprocessed food products, as opposed to processed foods, other traded and nontraded products. The results also support the view that, except for nontraded products, the speed at which prices adjust to the long‐run equilibrium is slower for cities that are farther apart.     

Volatility in Cereal Prices: Intra‐ Versus Inter‐annual Volatility

Intra‐annual (within crop year) price volatility and inter‐annual (between crop years) price volatility are measured for wheat, maize, rice, barley, oats and rye. A set of explanatory variables is used in a pooled regression to explain variations in these price volatilities. With low cereal stocks, supply (yield) shocks (defined here as volatilities, as for the price volatilities) mostly influence inter‐annual volatility while other influential factors are the crude oil price and exchange rate. Cereal demand and interest rate shocks combined with low stocks affect intra‐annual volatility, while other explanatory factors include exchange rate and crude oil price shocks. The derivatives market activity appears to have no significant effect on either intra‐ or inter‐annual volatility. In contrast, large cereal stocks and a well‐functioning international cereal market reduce the effects of shocks in the explanatory variables on both intra‐ and inter‐annual volatilities.     

Asymmetric price volatility transmission between food and energy markets: The case of Spain

The proportion of agricultural production that is being transformed into biofuels has been growing worldwide over the last decade. This has spurred the food versus fuel debate. This article aims at shedding light on this issue by studying price volatility relationships between food and biofuel prices in Spain. We use an asymmetric MGARCH model to evaluate volatility spillovers between the Spanish biodiesel blend and refined sunflower oil prices. Empirical results confirm that there are bidirectional and asymmetric volatility spillovers between these two prices.     

Market integration between surplus and deficit rice markets during global food crisis period

Applying the maximum‐likelihood method of co‐integration, this study analysed spatial market integration between an adjacent rice surplus market (India) and deficit markets (Bangladesh and Nepal). The main focus is on the government policies of these three rice‐producing countries which have been imposed to reduce domestic price volatilities in rice markets during the recent ‘global food crisis’ in 2007–2008. The co‐integration tests find that domestic rice prices of India, Bangladesh and Nepal are integrated both in short‐run and long‐run periods despite the imposition of export restriction policies by India. The reason that prices are transmitted so effectively is most likely to be the widespread informal cross‐border trade through the porous borders among India, Bangladesh and Nepal.     

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.