Table 22

Nonexperimental Lalonde Data: Estimates of Average Treatment Effects (standard errors in parentheses)

CovariateFull SampleTrimmed Sample
1 BlockMatch1 Block2 Blocks4 BlocksMatch
Number−8.50
(0.58)
1.72
(0.90)
1.72
(0.74)
1.81
(0.75)
1.79
(0.76)
1.98
(0.85)
Few0.69
(0.59)
1.73
(0.90)
1.81
(0.73)
1.80
(0.73)
2.10
(0.75)
1.98
(0.85)
All1.07
(0.55)
1.81
(0.90)
1.97
(0.66)
1.90
(0.67)
1.93
(0.70)
2.06
(0.85)