Modeling international trade flows and market shares for agricultural commodities: a modified Armington procedure for rice

The Armington procedure (AP) has become increasingly popular in agricultural trade analyses. However, some arguments have arisen concerning the relevance of using the procedure for such analyses. This study examines the assumptions commonly made when using the Armington procedure and suggests modifications for agricultural trade analyses. Results from models utilizing rice-trade data suggest that the assumptions of the single constant elasticity, in particular, may not be appropriate for analyzing agricultural trade. These results also suggest that, with proper modifications, the AP can be applied to agricultural trade. Further, results of a modified Armington procedure indicate that trade in rice exports is highly competitive and that changes in market shares of individual exporters are not independent of changes in budget expenditure allocated to imports.     

AGRICULTURAL FLOOD ALLEVIATION BENEFIT ASSESSMENT: A CASE STUDY

The cost of flooding on farm land depends on land use, on the frequency, seasonality, duration and depth of flooding, and on water quality. This paper describes a method to calculate the average annual cost of flooding and the extra benefits or costs associated with given changes in flooding regime, illustrated by means of a simplified case study which examines the agricultural benefits of reduced summer flooding on grass in an area of environmental importance. Using hydrological and agro-economic data, the method derives the cost of individual flood events occurring in any one month for a given land use, weights these according to observed seasonality of flood flows, and derives average annual costs per hectare and for the floodplain as a whole for given levels of flood risk. The method is useful for appraising river flood alleviation schemes whereby the effects of changes in flood risk, flood seasonality or land use can be assessed.     

GOAL PROGRAMMING AND MULTIPLE CRITERIA DECISION-MAKING IN FARM PLANNING: AN EXPOSITORY ANALYSIS

Several paradigms can be used to analyse multiple-criteria decision-making problems. Of these goal programming is probably the most widely used one, at least in management science. Goal programming seems to offer considerable potential for application to multiple-criteria problems in farm planning. However, its applications in agricultural economics have been few and far between. Even these attempts seem to suffer from some serious misconceptions. In this paper an effort is made to explain the structure of a goal programming model by deriving it from the familiar paradigm of linear programming. This is done to put the potential usefulness of goal programming and its relationship to linear programming in perspective, and to encourage further applications to multiple-criteria decision-making in farm planning.     

TOWARDS PRACTICAL GUIDELINES FOR MULTIPLE USE MANAGEMENT*

The general acceptance of multiple use as a desirable management goal has not been matched by practical guidelines to implement and achieve that goal. As Pearse [5] rightly noted, the most serious obstacles to applying multiple use principles are usually the lack of appropriate data and lack of established methodology. This study did not face prohibitive problems in valuing extra-market goods, but as with all multiple use studies, it did face the problem of applying the standard economic model of the multi-product firm. It is hoped this particular empirical application of the model contributes generally to the provision of guidelines for multiple use management.     

AIDing contraception: HIV and recent trends in abortion

Using a difference-in-differences estimation framework and state-level data, we investigate the potential role of HIV/AIDS in contributing to declining abortion utilization in the United States. Our results suggest that the perceived risk of HIV contraction negatively affected unwanted pregnancies. Specifically, a 10% increase in HIV incidence is associated with 0.34–1.1% fewer abortions per live births, an effect that can account for at least one-tenth of the sharp decline in abortions observed from the early 1980s to mid-1990s.     

Technical efficiency of sawnwood production in Ondo and Osun states,Nigeria

This study quantified technical efficiency and the determinants of observed technical inefficiency of sawmills in Nigeria. A two-stage sampling technique was used to select 170 sawmillers in Ondo and Osun states, while questionnaire was used to obtain data from them between October and December 2003. The stochastic frontier approach was used to estimate technical efficiency of both small- and medium-scale sawmills, while the ordinary least square (OLS) regression analysis was used to estimate the determinants of the observed technical inefficiency. Empirical results indicate that medium-scale sawmillers are more efficient than their small-scale counterparts. However, both groups of sawmillers in Nigeria have potentials to expand their output.