Table 4

Average Treatment Effect of Purchase of Development Rights (PDR) Programs on the Rate of Farmland Loss and Farmland Acres Lost during 1978–1997: Matched over Full Sample and Restricted to within Same Time Period

Epan Kernel Matching, Bandwidth = 0.02 (Bootstrapped Std. Error)Uniform Kernel Matching, Bandwidth = 0.02 (Bootstrapped Std. Error)
Full SampleCommon SupportFull SampleCommon Support
Matching over full sample
     Rate of loss: impact of PDR programs−0.041 (0.01)−0.039 (0.01)−0.038 (0.01)−0.037 (0.01)
     Acres lost: impact of PDR programs−2,753 (1,126)−2,617 (965)−2,662 (1,052)−2,413 (971)
     Number of matched PDR counties184178184178
     Number of matched non-PDR counties846846846846
Matching within time period
     Rate of loss: impact of PDR programs−0.036 (0.010)−0.032 (0.01)−0.038 (0.01)−0.031 (0.01)
     Acres lost: impact of PDR programs−1,876 (817)−1,952 (862)−1,932 (825)−1,913 (851)
     Number of matched PDR counties142132142132
     Number of matched non-PDR counties812812812812
  • Note: Bootstrapped standard errors are based on 2,000 iterations.