table 9

Fuzzy Regression Discontinuity Estimates of the Effects of Public Preschool Enrollment on Maternal Labor Supply, Single Mothers of Four-year-olds in the 2000 Census, Various Sample Widths

1234
With No Younger Children
Current employment0.0260.0360.0580.003
(0.224)(0.166)(0.168)(0.122)
Employment in prior year0.3610.2310.1840.069
(0.190)(0.124)(0.119)(0.085)
Weeks worked in prior year−3.423.222.361.81
(13.54)(7.66)(7.21)(4.83)
Usual hours per week in prior year7.635.427.282.05
(9.46)(6.17)(6.01)(4.26)
Wage and salary income, prior year4,3879,5488,1583,957
(8,518)(6,771)(7,008)(4,937)
Welfare receipt in prior year−0.067−0.064−0.093−0.009
(0.226)(0.153)(0.127)(0.084)
First stage estimate0.1410.1240.1070.111
(0.041)(0.022)(0.017)(0.012)
F−statistic12314190
Number of observations2,4717,29112,05423,617
With Younger Children
Current employment−0.955−0.745−0.341−0.495
(0.774)(1.126)(0.346)(0.358)
Employment in prior year−0.873−1.810−0.607−0.425
(0.782)(1.982)(0.340)(0.298)
Weeks worked in prior year−28.23−68.53−26.00−19.64
(36.09)(78.70)(16.55)(15.28)
Usual hours per week in prior year−45.25−54.67−19.91−15.35
(46.01)(67.67)(13.97)(12.61)
Wage and salary income, prior year4,29910,850−10,030−8,952
(24,807)(41,254)(15,500)(13,926)
Welfare receipt in prior year0.4950.1740.1080.269
(0.571)(0.641)(0.249)(0.273)
First stage estimate0.0800.0360.0850.067
(0.055)(0.035)(0.028)(0.021)
F-statistic21910
Number of observations1,0523,1995,22610,138
Width of sample in days103050100

Notes: Based on the author’s calculations using the 2000 Restricted Access Long Form Data. Standard errors are in parentheses. Population weights are used when available. Regressions include state fixed effects and the set of controls described in the text. Numbers in bold are significant at the 5 percent level or lower. F Statistics are of the test of the null in which the eligibility for public kindergarten has no effect on public kindergarten enrollment.