Post‐War Productivity Patterns in U.S. Agriculture: Influences of Aggregation Procedures in a State‐Level Analysis
利用48个州的年度数据，通过调整投入产出加总方式（如使用州级价格而非全国价格），重新测算美国农业的投入、产出和生产率变化，发现州级生产率增长与以往研究存在显著差异。
Abstract Annual data for forty‐eight states are used to account for changes in the composition of input and output aggregates over space and time, and thereby to obtain new evidence on changes in inputs, outputs, and productivity in U.S. agriculture. The measures change significantly when we use state‐specific rather than national prices and when we allow for changes in the composition of the aggregates, especially of labor and capital inputs. We compare our estimates and those reported by Ball et al. ( American Journal of Agricultural Economics 81(1999):164–79). The national estimates are similar but substantial differences are found in state‐level productivity growth.