bluuebunny/crossref_metadata_2025 huggingface dataset:
Sex‐specific differences in gonopore and gonadal growth trajectories in the brooding sea urchin, Abatus cavernosus (Spatangoida)
Authors: Gil Damián G. , Zaixso Héctor E. , Tolosano Javier A.
Published: January 2020

The heart urchin Abatus cavernosus shows sexual dimorphism characterized by the development of external brood pouches and the enlargement of gonopores in brooding females. Relationships between body size, gonopore size, and gonadal maturation in each sex were examined for inflection points using piecewise regression models (PRM). Opening of the gonopore occurred at 15.5 mm test length. Inflection points in the gonadal growth and gonopore diameter trajectories were clustered at smaller sizes in males (23 and 24.2 mm, respectively) than in females (25.1 and 25.9 mm), indicating sex‐specific differences in sexual maturation. Gonopore growth showed positive allometry at pre‐adult stages of development in both sexes, but isometry and negative allometry in adult females and males, respectively. Gonadal growth was initiated at smaller sizes and proceeded at a higher rate with increasing body size in males than in females. Identification of inflection points in gonopore and gonadal growth trajectories, using objective PRM, allows the determination of life stages and sexual maturation for individuals, thus providing a complementary tool for population studies.
Appraising Alternatives for Allocating and Cost Recovery for Irrigation Water in Egypt
Authors: Bowen Richard L. , Young Robert A.
Published: January 2020

Alternative approaches to allocating and recovering costs for water on Egyptian farms are proposed and evaluated in accordance with the societal objectives of allocative efficiency, equity of income distribution and cost recovery. A linear programming model of a study area in Egypt's northern Delta predicts farmers' response to the proposed cost‐sharing instruments over a range of water supply conditions. Transactions costs for each charging instrument are estimated and incorporated into the allocative. efficiency analysis. Flat land charges, supplemented by water quotas in the event of increasing water scarcity, best achieve societal objectives in the current and prospective Egyptian situation. Volumetric charging instruments were judged to be somewhat less desirable, due to higher tangible and intangible costs of implementation. The results highlight the importance of transactions costs, the degree of water scarcity and other governmental revenue raising policies in determining an appropriate charging mechanism.
Effects of Increasing Agricultural Productivity in a Multisectoral Model for the Philippines
Authors: Bautista Romeo M.
Published: January 2020

This paper investigates empirically the economy‐wide effects of agricultural productivity increases in the Philippines, reporting the results of a quantitative analysis based on a general equilibrium framework. A multisectoral, price endogenous model of the Philippine economy is employed, emphasizing not only agriculture but also other production sectors with which it closely interacts, as well as the distinction between rural and urban households in their income generation and consumption patterns. Among other findings, the differential effects on the real income of rural households vis‐a‐vis urban households arising from increased productivity in the various components of the agricultural production sector are striking. The resulting improvements in the trade balance and national income, among other macroeconomic variables, are also relatively significant. Moreover, there are significant differences in the economy‐wide effects among the four sectors of food and agriculture distinguished in the study. Particularly interesting is the highly favorable impact of rising productivity in the food processing sector on agricultural crop production and rural income, a linkage effect that has not received much attention in the development literature.
Biased Technological Change and Factor Demand in Postwar Japanese Agriculture, 1958‐84
Authors: Kuroda Yoshima
Published: January 2020

The objective of this study is to gain a better understanding of factor substitutions in postwar Japanese agriculture by shedding special light on biased technological change. Such biased technological change is first measured, then associated with the movements of factor prices, and then tested for the Hicksian induced‐innovation hypothesis. In addition, a decomposition analysis is carried out in order to quantitatively examine the importance of the biased effects for determining changes in factor‐cost shares and factor proportions during the 1958‐84 period.

A slightly modified Stevenson‐Greene model of the translog cost function is employed. This model has at least two important advantages over ordinary translog cost functions. First, it incorporates time into the model such that all coefficients of the ordinary translog cost function may change over time. This is more realistic than the ordinary translog cost function which assumes that all coefficients are constant over the period of estimation. Another attractive feature is that it enables us to test the induced‐innovation hypothesis directly. The model is applied to the 1958‐84 period by making use of farm‐level data.

The results show that technological change was biased towards saving labor and other inputs and using machinery, intermediate inputs, and land. This biased technological change is found to be, in principle, consistent with the induced‐innovation hypothesis. Furthermore, it is shown through decomposition analyses that the biased technological change had significant impacts on changes in factor‐cost shares and factor proportions during these years.

The empirical results of this study imply that technological change in Japanese agriculture has, in general, proceeded in a manner consistent with factor endowments conditions since the late 1950s. An implication of this study for agriculture in less‐developed countries is that agricultural policies seeking development through technological progress should be carried out so as to take advantage of peculiar factor endowments conditions in the individual countries.
A Dynamic Adjustment Model for U.S. Agriculture: 1948‐79
Authors: Vasavada Utpal , Ball V. Eldon
Published: January 2020

A multioutput model is developed within the adjustment cost framework to analyze the structure of dynamic adjustments in U.S. agriculture during the post‐war period. An important feature of this model is that the econometric model is consistent with dynamic economic theory. Fluctuations in capital stocks, variable inputs, and outputs are explained by changing opportunity costs. Empirical results indicated that durable equipment, farm‐produced durables, and family labor exhibited significant rigidity in adjustment as a response to exogenous shocks. Surprisingly, the hypothesis that real estate was a variable input could not be rejected. The univariate flexible accelerator hypothesis, which is widely maintained in most agricultural adjustment studies, is inconsistent with the data.
Impact of Risk on HYV Adoption in Bangladesh
Authors: Parikh Ashok , Bernard Andrew
Published: January 2020

The objectives of this paper are to develop a measure of risk aversion based on the safety‐first principle. The risk coefficient for a large number of farmers was positive indicating the tendency towards gambling in Bangladesh agriculture. Farmers who were near subsistence income (disaster level of income) tended to choose riskier crops such as HYV rice. The risk‐aversion variable was highly correlated with demographic and socioeconomic variables. Large holders of land tended to be relatively more risk‐averse than small holders of land and area allocated to HYV proportionally declined with increases in holding size.

A three‐equation model on HYV adoption decisions, fertilizer and hired labour was estimated with a risk‐aversion variable based on the safety‐first principle, and expected and significant signs were obtained with the risk‐aversion variable in HYV and hired labour equations.
Linkages between Regulated and Unregulated Markets: the Case of Milk Supply in Kenya
Authors: Howard Wayne H. , McDonald Ian
Published: January 2020

Linkages between the regulated and unregulated dairy markets in Kenya were examined using an econometric model of the fluid milk intake for eight processing plants. Counter‐intuitive results were obtained: an increase in the regulated price was significant in decreasing intake in the regulated market, indicating that a price increase in the regulated market also increased price and quantity supplied in the unregulated market. Lagged rainfall was a proxy for available feed and was highly significant in explaining milk intake in the regulated market.
Toward a Behavioral Model of Multiple‐Job‐Holding Farm Families
Authors: Eboli Maria G. , Turri Enrico
Published: January 2020

This paper applies a multidimensional method and a structural approach to the results of research based on a field survey on the origins of pluriactivity and on the attitudes of farm families toward multiple job‐holding and full‐time farming. Multiple correspondence analysis makes it possible to consider jointly, from a static and dynamic point of view, several quantitative and qualitative variables concerning the family, the farm, and the socio‐economic context. A typology of seven groups of farm families is established by means of cluster analysis.

The typology shows that the dichotomy between pluriactive and full‐time farms does not account for all of reality: a great deal of diversity exists within both groups. The major factors which explain pluriactivity and condition its performance are identified and interpreted. The implications, in term of agricultural, socio‐economic and environmental policy, of the evolution of the family farms of each type are then described and analyzed.

The essay concludes that future research on pluriactivity ought to pay more attention to the dynamic variables originating both within the farm families and in the socio‐economic context.
Evaluation of the Influence of Agricultural Price Policy on Cotton Production in Côte‐d'Ivoire
Authors: Berte Kama , Epplin Francis M.
Published: January 2020

In this paper the impact of the cotton pricing policy of the marketing board of Côte‐d'Ivoire is investigated. A theoretical model is developed to derive the price level which maximizes revenue generated from the marketing board's cotton transactions. A dynamic cotton supply function was estimated and used to compute elasticities. The estimates indicate that farmers in the Country response to price changes and that the pricing policy of the marketing board has been consistent with an objective of generating revenue for the government.
United States Demand for Coffee Imports
Authors: Goddard E.W. , Akiyama T.
Published: January 2020

The United States ‐ one of the world's largest coffee importers ‐ imports coffee beans from a variety of different countries. These countries are aggregated into five groups representing five broadly defined types of coffee. Imports of the five coffees over time are examined to determine price, expenditure and substitution elasticities. These elasticities reflect preferences as well a technical relationships in the form of blending recipes. The lower the degree of substitutability between the different types of coffee, the more inelastic the demand from the United States facing groups of exporting countries.

The results suggest rigidities in United States imports of coffee of different types. These rigidities are evidenced by substantial complementarity among the five coffee types. Preference patterns are very similar across a wide range of model specifications. There are differences in expenditure elasticities for different types of coffee in the United States.
Developing Country Interests in Agricultural Trade Reform
Authors: Tyers Rod
Published: January 2020

This paper examines whether developing countries, as a group, would be better off in the absence of agricultural protection in the industrial North and, if so, whether they should support reforms negotiated between the major players in the Uruguay Round. Results from the Tyers‐Anderson GLS model of world food markets suggest that the net effect of industrial country agricultural protection is beneficial to developing countries, though by only a small margin, even if its removal were to stimulate accelerated technical change in developing countries. The same is found to be true of partial reforms which are more palatable politically, such as quotas to reduce oversupply in the EC. Of course, many developing countries, including those which are members of the Cairns Group, are badly hurt by protection in the North. Unfortunately, however, they and the other members of that group stand to gain comparatively little from the reduction of oversupply in the EC through quotas.
Spillover Effects of International Agricultural Research: CIMMYT‐based Semi‐Dwarf Wheats in Australia
Authors: Brennan John P.
Published: January 2020

The spillover effects of agricultural research are of interest because research‐induced supply shifts in non‐target regions can reduce the benefits for producers in the target regions. The introduction of semi‐dwarfing genes in wheat into Australia provides an example of spillover from the CIMMYT program. Australia's wheat‐growing environments were not those for which the CIMMYT material was specifically targeted. However, some of these lines were introduced into Australia and used in breeding programs to produce important supply shifts in Australia. An examination is made of the effects that the spillover had in Australia.

Using an index of varietal improvement, with its attendant qualifications, an estimate of the extent of that shift resulting from the CIMMYT‐based varieties was obtained. While the extent varied widely between states, the shift was found to be between 0.2 and 7.7%, with an overall average for Australia of 3.5% by 1983. On the basis of an assumption of perfectly elastic export demand for Australian wheat, the estimated total cost savings to Australian producers were US$747 million (in 1983‐84 dollars) for the period 1974 to 1983, or an average of US$75 million per year. The annual contribution of Australia to CIMMYT has averaged approximately US$340,000 in recent years, while the average annual expenditure on wheat breeding in Australia has been US$4 to 5 million. On the basis of pedigrees, approximately two‐thirds of the cost savings of CIMMYT‐based varieties could be attributed to CIMMYT per se, with the remaining one‐third attributable to the inputs of the Australian wheat breeders.
Productivity of Agricultural Labour and Land: An International Comparison
Authors: Sharma Kailash C. , Rao D.S. Prasada , Shepherd W.F.
Published: January 2020

This paper examines partial agricultural land and labour productivity in 1975 and 1980, for different world regions. The results suggest that land and labour productivity are higher in developed countries relative to developing countries. However, agricultural labour productivity differences are more marked than those for agricultural land productivity. The productivity values for 1975 and 1980 indicate a widening of productivity differences, more so in the case of agricultural labour than land.

The paper also proposes an alternative approach to estimating agricultural land and labour productivity. This approach, which regresses agricultural labour productivity on a given level of agricultural land productivity, suggests a narrowing of agricultural land productivity differences, relative to the initial approach, across Africa, Asia and Europe during the 1975‐1980 period. A brief discussion of the agricultural development policy implications of the results concludes the paper.
Multiple Leasing under Cropshare Tenancy — A Note
Authors: Taslim M.A.
Published: January 2020

This paper attempts to explain the perplexing tendency to multiple leasing by both landlords and tenants in some countries. It shows that if the negotiation of share contracts involves significant transaction costs and there is some uncertainty regarding the output on tenanted plots, a risk‐averse landlord maximizing expected utility will find it in his advantage to subdivide his land among several tenants and also permit his tenant to lease land from other landlords.
Building African Scientific Capacity for Agricultural Development
Authors: Eicher Carl K.
Published: January 2020

During Africa's first two decades of independence from 1960 to 1980, priority was given to increasing the size of national extension services because it was assumed that technology could be imported from industrial countries and the International Agricultural Research Centers. Over the past decade, donors have turned their attention to assisting national agricultural research systems (NARS). But many NARS are performing poorly and are faced with a high turnover of scientific staff and inadequate operating budgets. Moreover, the present donor‐financed project by project and country by country approach to building African scientific capacity is seriously flawed. This paper examines Africa's agricultural research history over the past six decades and draws lessons for strengthening national and regional agricultural research systems over the coming 30 years.
Small‐Ruminant Marketing in Southwest Nigeria
Authors: Francis Paul A.
Published: January 2020

This paper describes the structure of the small‐ruminant trade in southwest Nigeria, analyses the factors determining the price of animals, and examines the relationship of prices between markets. Animals imported from the north dominate the sheep and goat trades, and supply and prices are highly seasonal. However, multiple regression shows animal prices to be largely predictable in terms of the characteristics of the animal (breed, sex and live‐weight) and the market in which it is sold (location and month of sale). Prices are relatively closely correlated between markets over time, and price relationships between markets reflect the respective structures of the trade in northern and southern animals. Price margins between markets reflect the level of traders' commission and storage costs in addition to the direct costs of transport. The study concludes that there is no evidence for market inefficiency or segregation, and that there is considerable market potential for increased local production of sheep and goats. In policy terms, the market's efficiency implies that government involvement beyond its present, limited facilitative role would not be justified.
A test of the underinvestment, myopia and commodity bias hypotheses for U.S. agricultural research
Authors: Fox Glenn , Haque A.K. Enamul
Published: January 2020

Analysts of agricultural research policy in the United States of America have claimed that the overall level of public investment in agricultural research is less than what would be socially optimal, that the present composition of public research investment is excessively myopic in that too little basic research is performed relative to the level of applied research, and that the allocation of research resources among commodities is inconsistent with economic efficiency.

A non‐linear optimal growth model of the U.S. economy was developed to analyse these propositions. Strong support was found for the claim that the overall level of investment has been inadequate. No support was found for the contention that basic research has been relatively underfunded compared to applied research. Weak support was found for the view that crop research has suffered from more acute underfunding than has livestock research.
A test of whether millet acreage in Niger is determined by official or private market prices
Authors: Brorsen B. Wade , Adesina Akinwumi A.
Published: January 2020

Niger has two separate marketing channels for grain: one is the official system operated by the government; the other is a parallel channel of private traders. Researchers or policy‐makers wanting to study effects of price policies on producers are faced with two sets of prices. This paper seeks to answer the question, which prices matter? Non‐nested hypothesis tests are conducted for millet‐acreage response equations. The results show that prices from the larger private market are the prices that matter.
Modeling international trade flows and market shares for agricultural commodities: a modified Armington procedure for rice
Authors: Ito Shoichi , Chen Dean T. , Peterson E. Wesley F.
Published: January 2020

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.
Inefficiency due to tenancy protection: a new tenure problem in Taiwan
Authors: Huang Chung‐Huang
Published: January 2020

Fixed‐rent tenancy was traditionally regarded as equally efficient as owner‐cultivators. The counter‐example is, however, presented here. Specifically, tenants with fixed‐rent contracts and well protected by tenancy regulations may, in the long run, turn out to be less efficient than other farmers (e.g., owner‐cultivators and informal tenants), particularly when they do not heavily depend on farm revenue as major source of family income. On the other hand, tenants who are not benefited from tenancy regulations might not be less efficient than owner‐cultivators. The underlying implication is tenancy reform is not a panacea for improving farming efficiency; it may result in many negative effects in the long run.
Application of replacement theory in dairy cows and its use in disease treatment
Authors: Ngategize Peter K. , Harsh Stephen B. , Kaneene John B.
Published: January 2020

A model to simulate the costs and returns of an individual dairy cow over 14 years under various assumptions of genetic potential, health status and management was developed especially to evaluate the effects of diseases that reduce production and reproduction efficiency and to evaluate alternative management interventions. Data were collected from the Food Animal Health Resource Management System (FAHRMX), Today's Electronic Planning (TELPLAN), Today's Electric Farm Accounting (TELFARM) databases and secondary sources at Michigan State University. A case study of cystic ovaries was analysed using the model. The results showed that it is more economical to treat cystic ovaries than not to treat, and treatment with Gonadotropin Releasing Hormone (GNRH) was superior to Human Chrionic Gonadotropin (HCG). Four to five lactations were the optimum for keeping a dairy cow to replacement and it was estimated that there is a loss of US$0.45 per day of extended calving interval (days open beyond the optimal 70 days).
Managing multiple international risks simultaneously with an optimal hedging model
Authors: Sarassoro Gboroton F. , Leuthold Raymond M.
Published: January 2020

A risk management model based on portfolio theory which accounts jointly for price, quantity, interest rate and exchange rate risks is developed and applied to cocoa and coffee production and exports in the Ivory Coast. Utilizing commodity and financial futures markets jointly, the results show that a government export agency can reduce risks from 27% to 89% by following a multicommodity hedging program which manages several risks simultaneously. The model and technique developed are applicable to many multiproduct firm and international risk management situations.
Empirical testing of alternative price spread models in the South African maize market
Authors: Faminow Merle D. , Laubscher J.M.
Published: January 2020

Reduced‐form price spread models have been recently utilized by Wohlgenant and Mullen, and Thompson and Lyon to evaluate the economic factors affecting the marketing margins for agricultural products. Drawing on Gardner, Heien, Buse and Brandow, Waugh, Tomek and Robinson, and others they specify alternative retail‐farm price spread models and attempt to determine which best fit the data in the context of underlying theoretical rationale.

This paper continues in the spirit of Wohlgenant and Mullen, and Thompson and Lyon by evaluating alternative specifications of the retail‐farm price spread for white maize in South Africa. However, several important differences do remain. Wohlgenant and Mullen analyzed the price spread for beef using annual data, while Thompson and Lyon modeled the price spread for oranges using weekly data. The time period under consideration can be expected to affect the choice of model because fixed markup rules that might be evident using a short‐run period of analysis (e.g., Thompson and Lyon) become untenable over the long run with underlying supply and demand shifts. In this paper, monthly data, which may be interpreted as an intermediate‐run period, are used along with dichotomous supply‐demand shifters. In addition, Brorsen et. al. have shown that price uncertainty affects the price spread in the marketing channels of agricultural commodities. Thus, the analysis in this paper extends the framework of Wohlgenant and Mullen, and Thompson and Lyon to include measures of price risk. Finally, like Brorsen et. al. this study pertains to the grain market, while Wohlgenant and Mullen, and Thompson and Lyon studied the marketing margin for non‐storable commodities.
Modelling stochastic crop response to fertilisation when carry‐over matters
Authors: Jomini Patrick A. , Deuson Robert R. , Lowenberg‐DeBoer J. , Bationo André
Published: January 2020

Soils in a large part of Niger's agricultural area are sandy and very low in nitrogen (N), phosphorus (P) and organic matter. This low soil fertility combined with low and erratic rainfall constitutes a severe constraint on food cropping in the area. Although agronomists have advised chemical fertilization as a means of improving soil fertility, little fertilizer has been used in this area of the world.

The economic management of soil fertility in the agricultural area of Niger is analyzed using a dynamic model of farmer decision‐making under uncertainty. The model is based on agronomic principles of plant growth and accounts for the carry over of P, an immobile nutrient.

At current input prices, a soil P content of at least 14 ppm is found to be desirable. This target is above the natural soil fertility level of about 3 ppm. It can be maintained with a moderate annual application (12 kg P2O5 ha−1) of simple superphosphate. Results also suggests that returns to N fertilization are too low and variable to warrant the use of this input.
Development of agriculture in Ethiopia since the 1975 land reform
Authors: Belete Abenet , Dillon John L. , Anderson Frank M.
Published: January 2020

A stated objective of the Ethiopian Government since it came to power in 1975 has been to increase the production of crops for both domestic consumption and export. Consequently, a number of plans and programs have been proposed and implemented to bring about such development in Ethiopian agriculture. This paper mainly focuses 011 a macro review of the general course of Ethiopian agricultural development since the land reform of 1975. The food production in Ethiopia has lagged behind the population growth as evidenced by the gap between the growth rates of population (3%) and food production (1.8%) over the period from 1970 to 1983. Recently, this situation has, perhaps, further deteriorated. Seventy‐one percent of the total land mass is estimated to be suitable for agriculture, but only about 19% is cultivated. This suggests an underutilisation of land. Moreover, Ethiopia has a persistent subsistence production problem in agriculture. Agricultural research and education which are essential to development have not been given due attention by the policy makers. As a result, the agricultural technologies used by farmers have changed little in this century. Moreover, small‐scale farmers, although still the most potent economic force in the country, have not been given the incentives necessary to expand production, and currently receive less than adequate support from the central government. Some 85%, 50%, and 79% of total agricultural credit, fertiliser and improved seeds respectively go directly to socialist enterprises (state farms and producers' cooperatives) which, up to 1985, have jointly accounted for only 5% of the total cultivated land and 4% of the national crop production. The favouring of large‐scale and capital‐intensive state‐owned farming enterprises with credit, subsidies, and fiscal incentives, while neglecting smallholders, has contributed to the stagnation of agricultural production in Ethiopia. Overall, the analysis indicates that there has been no significant development of agriculture in Ethiopia following the 1975 land reform.
Economic factors affecting human fertility in the developing areas of Southern Africa
Authors: Fairlamb Cheryl D. , Nieuwoudt Wilhelmus L.
Published: January 2020

South Africa's annual population growth rate, in the traditional sector, is 3.5% (1980‐2000), a rate similar to those experienced in the rest of sub‐Saharan Africa, and over which the World Bank has expressed concern. For the purposes of this study, economic factors explaining family size choice in the traditional sector were examined and linkages between family size decisions and socio‐economic variables analysed. Household utility was maximised subject to resource constraints of time, labour and income, from which a demand curve for children was derived with emphasis on the opportunity cost of wives' time and the quantity‐quality trade‐off for children. A stratified sampling technique was used to collect data from KwaZulu households in South Africa. Regression analysis was used to estimate the demand function and principal components analysis confirmed the underlying theoretical linkages. Results show that wife's education (expected income or opportunity cost), child help (benefits) and desired family size were important explanatory variables. Three components extracted represented the substitution effect, the income effect and child investment theory. Results show that investment in education, taken as a proxy for expected earnings, is a strong policy option for reducing family size.
Induced technical change in centrally planned economies
Authors: Fan Shenggen , Ruttan Vernon W.
Published: January 2020

It has generally been assumed that the inferences of the induced technical change model with respect to the direction of technical change could not be expected to hold for the centrally planned economies. In this paper we test three hypotheses generated from the induced technical change hypotheses against the experience of centrally planned economies: (a) if land becomes increasingly scarce new technology will be biased in a land‐saving direction; (b) if labor becomes increasingly scarce new technology will be biased in a labor‐saving direction; and (c) changes in the land‐labor ratio have been induced by changes in relative factor endowments. The results suggest a bias toward mechanical and against biological technology regardless of factor endowments. This is consistent with the well known ideological or policy bias in a number of centrally planned economies toward a capital‐intensive development strategy.
Evaluating the economic impact of quality‐reducing, seed‐borne diseases: Lessons from Karnal bunt of wheat
Authors: Brennan John P. , Warham Elizabeth J. , Byerlee Derek , Hernandez‐Estrada Julio
Published: January 2020

Estimates of aggregate disease costs can be used for assigning research resources or to evaluate control measures. Most diseases cause production losses, but others affect quality and marketability. Seed‐borne diseases also cause problems for the seed production and distribution industry. The aim in this paper is to examine issues relating to the economic impact of a quality‐reducing, seed‐borne disease, and to highlight differences compared to non‐seed‐borne diseases affecting yield only.

Economic evaluation of quality‐reducing, seed‐borne diseases needs to incorporate impacts of trading restrictions such as quarantines or embargoes imposed by purchasers. The costs of measures taken to control diseases also represent part of the economic impact of the disease. Full economic costs of a disease include the direct (yield and quality) costs and costs of the control measures. The costs of Karnal bunt of wheat in Mexico were found to include many control costs that have often been overlooked.

The optimal amount of resources to invest in controlling a disease depends on the likely annual costs of the disease and of control measures. Before implementing disease control policies, both the costs and the benefits of the policies need to be considered, taking the risks of each option into account, to ensure that the policy itself does not impose greater costs than the uncontrolled disease.
Interaction between livestock and feeds policies: evidence from Southeast Asia
Authors: Rae Allan N.
Published: January 2020

Consumption of livestock products in Southeast Asia could continue to increase rapidly, as has been the case in Northeast Asia. The extent to which domestic producers may respond to these demand developments will be influenced by government interventions in both livestock product and feeds markets. The paper analyses the net contribution of livestock product and feed price distortions on the effective rate of protection, and whether intervention in the commodity market is augmented or offset by intervention in the feeds market. While policy‐induced distortions were found to exist in the livestock sectors of Thailand and Malaysia, especially in beef and dairy production, the contribution of feeds policies to these distortions was minimal. In contrast implicit taxes on feeds were high in Indonesia and the Philippines. In the latter, support on product prices was sufficient to more than offset the tax on feeds so that effective protection remained positive. But in Indonesia both livestock and feeds policies worked to provide disincentives to livestock production. It is concluded that livestock and feeds policies should be formulated with regard to objectives and priorities within both sectors. This could require that greater emphasis be placed on feeds sector assistance policies that do not affect the price of feeds.
An econometric analysis of U.S. vital wheat gluten imports
Authors: Ortalo‐Magné François , Goodwin Barry K.
Published: January 2020

In light of the wheat wet milling industry's development in the E.C. and of the prominent role U.S imports play in the international market for wheat gluten, this paper discusses the international market for wheat gluten, an important component of processed grain products. An econometric analysis of the U.S. import demand for wheat gluten is undertaken. The price of flour, income, and the U.S. value of wheat protein are found to be important determinants of wheat gluten imports.
Estimating the effectiveness of extension information systems using farm trials and subjective probabilities
Authors: Howard Wayne H. , Blake Robert W. , Knight Thomas O. , Shumway C. Richard , Tomaszewski Michael A.
Published: January 2020

A method of combining survey data and Dairy Herd Improvement Association (DHIA) records to achieve low cost farm trials is presented. Farm trials and surveys of current practices and production responses are useful to identify yield gaps between expectations predicted from experimental findings and actual field results. Different management schemes can be ranked using subjective probabilities and stochastic dominance to enhance successful implementation of research findings and to increase the feedback between researchers, extension workers, and producers.

A survey of current masitis control practices and expected milk yield response is the example. Combining survey results with DHIA records allowed estimating the relationship between somatic cell counts (SCC) and milk yield. Eliciting beliefs about the relationship between SCC and milk yield showed that producers agreed with predictions from the statistical model. Subjective probabilities about SCC and mastitis control practices showed that our sample of experts and producers consistently ranked the different practices but extension agents had no consensus about the the most or least effective ones.
Frontier production functions and technical efficiency: a survey of empirical applications in agricultural economics
Authors: Batiese George E.
Published: January 2020

The modelling and estimation of frontier production functions has been an important area of econometric research during the last two decades. Försund, Lovell and Schmidt (1980) and Schmidt (1986) present reviews of the concepts and models involved and cite some of the empirical applications which had appeared to their respective times of publication.

This paper seeks to update the econometric modelling of frontier production functions associated with the estimation of technical efficiency of individual firms. A survey of empirical applications in agricultural economics is an important part of the paper.
Intervention bias in agricultural policy
Authors: Myers Robert J.
Published: January 2020

This paper re‐examines the motivation for government intervention in agriculture to support farm prices and incomes. A model is outlined in which the government has a preference for higher farm incomes but fails to provide farmers with the socially optimal level of price support, even when one accepts the government's income redistribution goals as a valid reflection of social preference. It is shown that agricultural policy has an intervention bias: government price supports generally are higher than would be socially optimal. The source of the intervention bias is a time inconsistency in optimal agricultural policy formation, caused by the government's inability to precommit to a rule for setting future price support levels. Simulation results indicate that in some circumstances the intervention bias in agricultural policy can be substantial.
Differentiated products and supply controls in the analysis of agricultural policy reform: the case of tobacco
Authors: Beghin John , Chang Ruey‐er
Published: January 2020

With a multi‐market model of the U.S. tobacco and cigarette industries, we analyze the impact of a reduction in the assistance to U.S. tobacco producers by relaxing production quotas with nonbinding price support and by lowering tariffs on tobacco imports. The results show the importance of incorporating differentiated product and supply control assumptions into agricultural policy analysis.
Relationship between agricultural growth and farm imports in LDCs: a Sims' causality test based on 35 countries
Authors: Wu Xiling , Yao Xianbin
Published: January 2020

Previous empirical studies on the relationship between agricultural growth and farm imports in the LDCs suffer from serious methodological defects, which to some extent may invalidate their results and interpretations. This study used Sims' causality test to examine interactions between agricultural output and agricultural imports for 35 LDCs individually. It was found that there was no causality from agricultural output to agricultural imports for a majority of countries under study. For countries where agricultural growth did have a causal effect on agricultural imports, the effect was positive in some countries and negative in others.
Will developing country debt forgiveness increase agricultural trade?
Authors: Pick Daniel , Krissoff Barry
Published: January 2020

Latin American countries are important customers in international agricultural trade. However, between 1981 and 1987, U.S. agricultural exports to these countries declined by almost 50%. One explanation for the above decrease is the change in financial conditions facing many countries in this region. Outstanding debt in the Latin American countries continued to rise through the 1980's, reaching over $120 billion for Brazil and Mexico by 1987.

In this paper, we develop an import model which considers the effect of the debt crisis on the ability of developing countries to purchase agricultural commodities in world markets. We estimate the model for four countries: Mexico, Brazil, Chile, and Venezuela.

The estimated results are used in a simulation model to obtain the effects of a 50% debt forgiveness scenario. Results indicate only a modest improvement in agricultural imports of the four Latin American countries considered in this study. These four countries would expand agricultural imports by $400 million per annum given the debt reduction.
Intra‐annual sheep price patterns and factors underlying price variations in the central highlands of Ethiopia
Authors: Andargachew K. , Brokken Ray F.
Published: January 2020

A sheep market survey was undertaken to determine the effects of certain animal and market characteristics on price and the pattern of sheep prices in relation to seasons. Nine key Ethiopian central highlands markets were surveyed for a period of one year in 1989. Each market was surveyed once a week on the main market day. Price, weight, sex, age, colour, condition score, breed type and buyer's purpose were recorded for all completed transactions as well as the numbers offered and sold on each market day. A total of 50062 cases were recorded.

Three markets, each representing redistributive, intermediate and terminal markets, as identified by the distribution in buyer's purpose were chosen for further analysis. Considerable weekly price variation was evident in these markets. Prices were also seasonal with higher premiums paid during some religious festivals. Animal characteristics (weight, age, condition, sex, colour) as well as buyer's purpose and seasons were variably important in explaining variation in price among animals within weeks. Variations in the composition of these characteristics from week‐to‐wcek were among factors underlying changes in weekly mean prices. R2 varied from 0.2659 to 0.3583 in the quadratic price per kg model and from 0.7822 to 0.8413 in the quadratic price per head model in the three markets. However, it was found that price per head was predicted equally well overall by estimated price per kg multiplied by actual weights and that because of wide variation in weights, both within and between weeks, price per kg is more useful market information.
A markup over average cost pricing rule for meat and poultry in the United States
Authors: Langlois Catherine C.
Published: January 2020

This paper tests the hypothesis that meat and poultry wholesalers choose their inventory levels together with wholesale price so as to maximize profit made over the sales time of their stock. The behavioral assumption predicts that markup over average cost will match the inverse of the price elasticity of the sales time of inventory. Price elasticity of inventory sales time is estimated for beef, pork and poultry accounting for the simultaneity between these pricing decisions by adopting a systems approach. The estimated range for the inverse of these elasticities includes all the markups applied over the sample range of the time series.
Implications of agricultural trade liberalization for the developing countries
Authors: Brandão Antônio Salazar P. , Martin Will J.
Published: January 2020

The developing countries as a group could expect to experience only small welfare gains if they chose not to actively participate in agricultural trade liberalization and relied solely on the benefits of partial liberalization in the OECD countries. Participation along the lines of the Dunkel package, with the developing countries reducing positive assistance by less than the developed countries, would yield gains of the order of US $20 billion. More comprehensive participation in trade liberalization involving reductions of both positive and negative protection would almost triple these welfare gains. While some developing countries do not gain from trade liberalization even with full participation, the number of such countries and the magnitude of their losses are greatly reduced.
Price and quantity controlled agricultural markets and disequilibrium econometrics: a survey
Authors: Oczkowski Edward
Published: January 2020

This survey reviews the literature on estimating single markets in disequilibrium in the presence of regulated price and/or quantity controls, e.g., minimum price regimes and/or marketing quotas. Most of the literature is found to describe pure econometric technique, with only a few applications having emerged to date. Various reasons for the broad non‐acceptance of this literature are offered, including a perceived lack of realism. Proposals to close this econometric theory–application gap are put forward, including: the use of effective demand concepts in specifying demand and supply functions; synthesizing some closely related literature on agricultural price/quantity controls with disequilibrium econometrics (i.e., endogenous government policy and the effects controls have on yield uncertainty and price risk); and outlining more ‘applicable’ econometric technique extensions.
Measuring the sustainability and economic viability of tropical farming systems: a model from sub‐Saharan Africa
Authors: Ehui Simeon K. , Spencer Dunstan S.C.
Published: January 2020

New technologies must be developed in sub‐Saharan Africa which are sustainable and economically viable. This paper discusses a methodology for measuring the agricultural sustainability and economic viability of tropical farming systems for new technology evaluation. The approach is based on the concept of interspatial and intertemporal total factor productivity, paying particular attention to valuation of natural resource stock and flows. Agriculture is a sector which utilizes natural resources (e.g. soil nutrients) and the stock and flows of these resources affect the production environment. However, in many cases, the stock of these resources is beyond the control of the farmer and must be accounted for in an agricultural sustainability and economic viability measurement. For example, soil nutrients are removed by crops, erosion or leaching beyond the crop root‐zone, or other processes such as volatilization of nitrogen. Agricultural production can also contribute to the stock of some nutrients by leguminous plants such as agroforestry systems. Using a data set available at the International Institute of Tropical Agriculture, we compute the intertemporal and interspatial total factor productivity indices for four cropping systems in southwestern Nigeria using stock of major soil nutrients as the natural resource stock. Results show that the sustainability and economic viability measures are sensitive to changes in the stock and flow of soil nutrients as well as the material inputs and outputs. Where the contribution of natural resource stock and flows are important (such as in the case of alley cropping), the measures provide markedly different results from conventional TFP approaches. The advantage of this approach is that interspatial and intertemporal total factor productivity measures are computed using only price and quantity data, thus eliminating the need for econometric estimation.