An Analytical Model of Farmers' Demand for Replacement Seed
构建了一个预测农民何时购买新种子的模型，结合产量潜力提升和种子折旧假设，并用巴基斯坦小麦数据验证，发现时间跨度影响参数效果，建议改善信息而非补贴。
Abstract Seed replacement choices differ from decisions about other inputs, such as fertilizer, because the farmer can reproduce seed. Assumptions about rates of improvement in yield potential and depreciation of retained seed are combined with behavioral assumptions and price and technical information to develop a model predicting the number of years before a farmer will buy new seed. Parameter estimates for wheat in Pakistan are fed into the model and results compared with observed replacement times. Time horizon strongly conditions effects of model parameters. To speed varietal change, better information for farmers is likely to be preferred to seed subsidies.