Summary: In recent years, a large number of computer-based models have been developed to help the agricultural community analyze trends, identify problems, and evaluate policy alternatives.
Over 50 models with potential for food and agricultural issue analysis were identified. These models vary by scope, size, methodology, and issues covered. They can be viewed as a hierarchical set of analytical tools which can be used to address several levels of problems, such as local issues of a specific crop; regional issues involving several farm inputs; national issues integrating nutrition with production policies; or global problems addressing population, wealth, and food. Many of the models identified are single or multicrop models and are usually confined to a particular region of the world. Other models are designed to aid understanding of specific policies or issues such as grain reserve costs under varying conditions. Still others are highly aggregated, treating the agriculture community as a whole, and are intended to predict general levels of activity over the short run. A smaller number of large-scale models exist that are not limited to any particular timeframe and, in some cases, are actually a series of interacting submodels combining agricultural and nonagricultural issues. These models attempt to portray key factors such as demography, environment, and pollution that influence the system.
