Summary statistics for acc_aux dataset : by Jean Roth , jroth@nber.org , 18 Apr 2016 Variable | Obs Mean Std. Dev. Min Max -------------+--------------------------------------------------------- year | 40,741 1989 0 1989 1989 state | 40,741 27.19072 16.06529 1 56 county | 40,741 85.88746 91.25989 0 999 fatals | 40,741 1.118824 .421611 1 21 st_case | 40,741 272782.6 160405.5 10001 560114 -------------+--------------------------------------------------------- a_crainj | 40,741 1 0 1 1 a_region | 40,741 5.267274 2.475965 1 10 a_ru | 40,741 1.436857 .4974855 1 3 a_inter | 40,741 1.896296 .3150945 1 3 a_relrd | 40,741 2.094696 1.411474 1 6 -------------+--------------------------------------------------------- a_intsec | 40,741 1.784959 .4132389 1 3 a_roadfc | 40,741 3.957414 1.530841 1 7 a_junc | 40,741 1.835301 .4921293 1 4 a_mancol | 40,741 1.959672 1.291021 1 7 a_rd | 40,741 3 0 3 3 -------------+--------------------------------------------------------- a_tod | 40,741 1.559387 .5116119 1 3 a_dow | 40,741 1.441914 .5001666 1 3 a_hr | 40,741 1.957831 .2009766 1 2 a_ct | 40,741 1.475148 .6043145 1 3 a_lt | 40,741 1.885275 .3186934 1 2 -------------+--------------------------------------------------------- a_mc | 40,741 1.92359 .2656555 1 2 a_spcra | 40,741 1.662944 .47271 1 2 a_ped | 40,741 1.840087 .3665295 1 2 a_pedal | 40,741 1.979456 .141855 1 2 a_roll | 40,741 1.752682 .4314587 1 2 -------------+--------------------------------------------------------- a_polpur | 40,741 1.993692 .0791739 1 2 a_posbac | 40,741 2.199578 .8983735 1 3 a_d15_19 | 40,741 1.819813 .3843479 1 2 a_d16_19 | 40,741 1.825115 .3798736 1 2 a_d15_20 | 40,741 1.774674 .4178019 1 2 -------------+--------------------------------------------------------- a_d16_20 | 40,741 1.779927 .4143008 1 2 a_d65pls | 40,741 1.872119 .3339614 1 2 a_d21_24 | 40,741 1.817628 .3861552 1 2 a_d16_24 | 40,741 1.614369 .48675 1 2 a_dist | 40,741 1.897106 .303824 1 2 -------------+--------------------------------------------------------- a_drowsy | 40,741 1.966594 .1796969 1 2 by Jean Roth , jroth@nber.org , 18 Apr 2016