Table 1 Estimated impact of GE varieties on pesticide use, average impact over 1998–2011 (assumes βt = β, ∀ t).

N = number of observations. SEs (in parentheses) are clustered at the farmer level. The model includes time fixed effects, CRD-specific time trends, and individual (farmer) fixed effects. *P < 0.05, **P < 0.01, ***P < 0.001. a.i., active ingredient.

Soybean herbicidesMaize herbicidesMaize insecticides
a.i. kg/haEIQ kg/haa.i. kg/haEIQ kg/haa.i. kg/haEIQ kg/ha
Gi0.3021***0.0045−0.0329*−0.2590***−0.0129***−0.0122***
(0.0097)(0.0122)(0.0150)(0.0156)(0.0014)(0.0014)
N86,73686,736134,264134,264134,264134,264
R20.0670.0280.0220.0270.0390.051