A systems analysis of the guyanese livestock industry

This paper attempts to contribute to the capability for livestock sub-sector analysis. A model structure which offers potential for evaluation of changes of policy, available production technology, or factor and product market conditions is described. The structure integrates a multi-year biological cattle simulator with a price endogenous model of the cattle sub-sector to yield a model designed to simulate aggregate behaviour of profit maximising cattle producers interacting through competitive factor and product markets. The general model structure is specified to reflect conditions in Guyana, South America. The model, specified for Guyanese conditions, is used to evaluate the probable impact of a number of technical and economic changes in the system.     

佛罗里达州柑桔投资的远景展望——GAMS仿真的案例

运用GAMS仿真展示了美国佛罗里达州柑桔生产投资的经济远景。仿真动态地、定量地回答了长期投资决策中的五个关键因素:期望净投资回收率、最低竞争价格、最大可接受的贷款利率、新建桔园的最优种植计划、最早获得盈利的年份(以净现值为表征)。该项研究有助于投资者作出正确的投资决策。     

A BIOECONOMIC MODEL FOR CHAM SCALLOP (PATINOPECTEN YESSOENSIS) AQUACULTURE IN KOREA

A bioeconomic model of cham scallop aquaculture in Korea was used to determine an optimal farm grow-out strategy. The model used estimated cost functions for two culture methods and growth functions based on three environmental characteristics for each region (Kojin and Chumunjin). Stochastic growth was incorporated using probabilities of alternative environmental states (based on expected levels of water temperature, salinity, and dissolved oxygen) by region, culture method, and month. The model revealed a 26% potential increase in net present value from altering management of a single rotation. Optimal multiple rotations required up to four different rotations depending on the region and culture style. Farmers could increase economic returns by delaying harvest and subsequent plantings in order to market larger, more valuable scallops. Resource managers could increase resource rents by adjusting the licensing system to account for regional-style differences and by targeting the planned aquaculture investments.     

Analyzing Production Feasibility and Market Potential For Florida Aquaculture Catfish Products

A spatiotemporal linear programming model (GAMS) was constructed to simulate the catfish production and marketing system in the U.S. in order to study the economic feasibility of Florida entering the aquaculture catfish industry. Evaluation of base model results and sensitivity analysis were used to identify constraints to the potential expansion of the catfish industry in Florida. Results indicated production and processing costs were more important in determining the locus of production and processing than were processing capacity, storage costs and capacity, and transportation costs. Thus, existing industry geographic concentration is likely to continue, but small new processing plants could develop proximate markets for fresh product.