Peter Hazell

A Linear Alternative to Quadratic and Semivariance Programming for Farm Planning under Uncertainty

Quadratic decision criteria for farm planning are theoretically appealing but difficult to handle computationally. This paper reviews the advantages of the quadratic approach and develops a linear alternative which, while retaining most of the desired features of the quadratic models, can be readily solved on conventional linear programming codes with the parametric option.

Productivity Effects of Indigenous Land Tenure Systems in Sub-Saharan Africa

This article uses household survey data from Ghana, Kenya, and Rwanda to test if the indigenous land rights systems in sub-Saharan Africa are a constraint on agricultural productivity. Rights which farmers hold over individual parcels of land vary widely, and are in many cases surprisingly privatized. Yet with few exceptions, land rights are not found to be a significant factor in determining investments in land improvements, use of inputs, access to credit, or the productivity of land. These results cast doubt on the need for ambitious land registration and titling programs at this time.

Farm-nonfarm linkages in rural sub-Saharan Africa

This paper is an accumulation, over the past 25 years, of a body of detailed work examining the structure of Africas rural, nonfarm economy. First, it systematically reviews empirical evidence on the nature and magnitude of the African rural, nonfarm economy. It then explores differences across locality and size, across countries and over time, in an effort to assess likely patterns of growth. A subsequent review of key production and consumption parameters allows an estimate of the magnitude of the agricultural growth multipliers in Africa. The paper concludes with a brief discussion of policies and programs that will be necessary if farm-nonfarm growth linkages are to achieve their full potential.

Targeting public investments by agro-ecological zone to achieve growth and poverty alleviation goals in rural India

Abstract This paper shows that improved technology and rural infrastructure have made important contributions to agricultural growth and poverty reduction in India. However, these effects have varied widely across agro-ecological zones. In the past, the government has devoted more resources to irrigated areas, and this has led to significant production growth and poverty reduction in those areas. However, as investments in irrigated areas continue to increase, their marginal returns diminish, and it is now in many of the rainfed areas, including some of lower agricultural potential, where the marginal returns from additional government investments in technology and infrastructure are largest.

The impact of the green revolution and prospects for the future

This article addresses some of the issues considered to be of great importance for continued success of the Green Revolution. The most recent data on its impact on food production are discussed first. Then follows a discussion of the impact on production fluctuation. Current evidence of the impact on poverty and nutrition is summarized in the third section. Recent research has shown that the multiplier or linkage effects of technological change may be very important for assuring a desirable path of self-sustaining growth. This issue is dealt with in the fourth section, followed by a discussion of the role of women in technological change, an important growth as well as equity issue which has received little attention until recently. Then follows a brief assessment of the actual and potential environmental effects. A number of other issues with important implications for the future contribution of technological change, such as future control over germplasm, organization of and control over the international agricultural research institutes, the needs for institutional and policy changes in many developing countries, and the need for new technology to facilitate a solution to the acute food problem in Sub-Saharan Africa, are discussed in the last section

Modeling agricultural growth multipliers

Agricultures potential as an engine of third world growth depends, in large part, on the size of the production and consumption linkages it stimulates in rural regions. Current estimates of agricultural growth multipliers within rural regions vary widely, not only because economic structures differ across regions but also because the array of fixed-price models most commonly used embody widely differing basic assumptions. Among fixed-price models, the semi-input-output formulation projects the most plausible multipliers. But even they overstate the magnitude of growth multipliers by 10% to 25% according to the price-endogenous model developed here.

Competitive Demand Structures under Risk in Agricultural Linear Programming Models

A method is presented for solving agricultural sector models under risk to obtain perfectly competitive levels of outputs and prices in all product markets when producers behave according to an E, V decision criterion. The nature of market equilibrium behavior is considerably more complicated under risk than in a deterministic setting. This presents difficulties in designing models which will always provide meaningful economic answers. These difficulties are overcome by stipulating conditions under which the proposed model is applicable. The resultant model is a quadratic programming problem, and linearization techniques are suggested which enable solutions to be obtained through conventional linear programming computer codes.

Agricultural Technology and Farm-Nonfarm Growth Linkages

Agricultural growth stimulates rural nonfarm activity by boosting demand for production inputs and consumer goods. But different kinds of agricultural technology promote different patterns of nonfarm linkages. To explore how key features of agricultural technology affect growth in the rural nonfarm economy, this paper reviews an array of cross-section and time-series evidence bearing on the dynamics of the rural nonfarm economy. Then, using consumption and production parameters associated with different agricultural technologies, it introduces a simple model which isolates the effects of different technologies on nonfarm growth linkages.

Measuring the Indirect Effects of an Agricultural Investment Project on Its Surrounding Region

Agricultural investment projects may generate important downstream benefits for the regions in which they are located. Using a semi-input-output model of the regional economy, an attempt is made to quantify the downstream benefits generated by an irrigation project in Malaysia. In aggregate the projects downstream effects on regional income were of an order similar to its direct effects, but the main beneficiaries of the downstream benefits were the nonfarm households. Each dollar of downstream income probably was supported by just over a dollar of additional investment in the local economy.

Sources of Increased Instability in Indian and U.S. Cereal Production

Recent growth in Indian and U.S. cereal production has been accompanied by a more than proportional increase in the standard deviation of production. This study applies variance decomposition procedures to state data on crop production to analyze the sources of this increased instability. It is found that production has become significantly more covariate between states and crops, largely because of increased yield variability and a loss in offsetting patterns of variation between crop yields in different states. These changes may be associated with more variable prices, with higher-yielding technologies, and with a narrowing of the genetic base.