Summary statistics for per_aux dataset : by Jean Roth , jroth@nber.org , 18 Apr 2016 Variable | Obs Mean Std. Dev. Min Max -------------+--------------------------------------------------------- a_age1 | 112,958 2.687061 .9443791 1 5 a_age2 | 112,958 3.602773 1.450257 1 6 a_age3 | 112,958 7.068574 2.599369 1 13 a_age4 | 112,958 3.970263 1.924988 1 8 a_age5 | 112,958 4.215133 2.345558 1 10 -------------+--------------------------------------------------------- a_age6 | 112,958 4.229873 2.328386 1 10 a_age7 | 112,958 6.126914 2.491525 1 12 a_age8 | 112,958 2.908417 1.767779 1 7 veh_no | 112,958 1.286974 .7515043 0 17 per_no | 112,958 1.73514 1.798635 1 67 -------------+--------------------------------------------------------- st_case | 112,958 270325 159970.9 10001 560131 year | 112,958 1988 0 1988 1988 a_ptype | 112,958 1.54283 .688378 1 5 a_rest | 112,958 1.835815 .6039158 1 3 a_alctes | 112,958 2.578799 .9289313 1 5 -------------+--------------------------------------------------------- a_hisp | 112,958 0 0 0 0 a_rcat | 112,958 0 0 0 0 a_hrace | 112,958 0 0 0 0 a_eject | 112,958 1.135723 .3581386 1 3 a_perinj | 112,958 3.91573 2.465202 1 6 -------------+--------------------------------------------------------- a_loc | 112,958 1.142549 .500685 1 4 by Jean Roth , jroth@nber.org , 18 Apr 2016