Slippage Effects of the Conservation Reserve Program: Reply
回应Roberts和Bucholtz关于保护储备计划滑移效应的研究，指出其认为区域CRP面积内生性的观点与实施规则和数据不符，因此外生性原假设未被统计检验拒绝。
Abstract Given that the Conservation Reserve Program (CRP) costs taxpayers $2 billion per year and remains the largest conservation program in U.S. history, Roberts and Bucholtz are to be commended for revisiting the slippage issue. However, their central point that regional variation in CRP acreage is endogenous is inconsistent with CRP implementation rules and data. Thus, it is not surprising that the null hypothesis of exogeneity cannot be rejected by statistical tests.