------------------------------------------------------------------------------- log: C:\Temp\web\class\5213\2008\HW_E10.2.log log type: text opened on: 25 Nov 2008, 12:10:02 . do "C:\Temp\web\class\5213\2008\HW_E10.2" . use "http://www.learneconometrics.com/data/stata/SeatBelts.dta", clear . xtset fips year, yearly panel variable: fips (strongly balanced) time variable: year, 1983 to 1997 delta: 1 year . . gen ln_inc=log(income) . regress fatalityrate sb_useage speed65 speed70 ba08 drinkage21 ln_inc age, > vce(hc3) Linear regression Number of obs = 556 F( 7, 548) = 88.52 Prob > F = 0.0000 R-squared = 0.5493 Root MSE = .0034 ------------------------------------------------------------------------------ | Robust HC3 fatalityrate | Coef. Std. Err. t P>|t| [95% Conf. Interval] -------------+---------------------------------------------------------------- sb_useage | .0040684 .0012436 3.27 0.001 .0016255 .0065113 speed65 | .0001479 .000413 0.36 0.720 -.0006634 .0009592 speed70 | .0024045 .0004809 5.00 0.000 .0014598 .0033491 ba08 | -.0019246 .0003676 -5.24 0.000 -.0026466 -.0012025 drinkage21 | .0000799 .0010237 0.08 0.938 -.001931 .0020908 ln_inc | -.0181444 .0011013 -16.48 0.000 -.0203077 -.0159811 age | -7.22e-06 .0001687 -0.04 0.966 -.0003386 .0003241 _cons | .1965469 .0093676 20.98 0.000 .178146 .2149478 ------------------------------------------------------------------------------ . . /* One sided t-test on the sb_useage coefficient is > not rejected at the 5% level. It actually has the > wrong sign. */ . . xtreg fatalityrate sb_useage speed65 speed70 ba08 drinkage21 ln_inc age, fe v > ce(cluster fips) Fixed-effects (within) regression Number of obs = 556 Group variable: fips Number of groups = 51 R-sq: within = 0.6868 Obs per group: min = 8 between = 0.1957 avg = 10.9 overall = 0.3896 max = 15 F(7,50) = 96.72 corr(u_i, Xb) = -0.1332 Prob > F = 0.0000 (Std. Err. adjusted for 51 clusters in fips) ------------------------------------------------------------------------------ | Robust fatalityrate | Coef. Std. Err. t P>|t| [95% Conf. Interval] -------------+---------------------------------------------------------------- sb_useage | -.0057748 .0016693 -3.46 0.001 -.0091276 -.002422 speed65 | -.000425 .0004555 -0.93 0.355 -.0013399 .0004898 speed70 | .0012333 .0003483 3.54 0.001 .0005337 .0019329 ba08 | -.0013775 .0003751 -3.67 0.001 -.0021308 -.0006241 drinkage21 | .0007453 .0007184 1.04 0.305 -.0006976 .0021883 ln_inc | -.0135144 .0023849 -5.67 0.000 -.0183047 -.0087241 age | .0009787 .0007461 1.31 0.196 -.0005199 .0024772 _cons | .1209958 .0184235 6.57 0.000 .0839912 .1580005 -------------+---------------------------------------------------------------- sigma_u | .00383103 sigma_e | .0017871 rho | .82128567 (fraction of variance due to u_i) ------------------------------------------------------------------------------ . xi: regress fatalityrate sb_useage speed65 speed70 ba08 drinkage21 ln_inc > age i.state, vce(cluster fips) i.state _Istate_1-51 (_Istate_1 for state==AK omitted) Linear regression Number of obs = 556 F( 6, 50) = . Prob > F = . R-squared = 0.8867 Root MSE = .00179 (Std. Err. adjusted for 51 clusters in fips) ------------------------------------------------------------------------------ | Robust fatalityrate | Coef. Std. Err. t P>|t| [95% Conf. Interval] -------------+---------------------------------------------------------------- sb_useage | -.0057748 .001751 -3.30 0.002 -.0092919 -.0022577 speed65 | -.000425 .0004778 -0.89 0.378 -.0013847 .0005346 speed70 | .0012333 .0003654 3.38 0.001 .0004994 .0019671 ba08 | -.0013775 .0003935 -3.50 0.001 -.0021677 -.0005872 drinkage21 | .0007453 .0007536 0.99 0.327 -.0007684 .002259 ln_inc | -.0135144 .0025018 -5.40 0.000 -.0185394 -.0084894 age | .0009787 .0007826 1.25 0.217 -.0005933 .0025507 _Istate_2 | -.0100326 .0046542 -2.16 0.036 -.0193809 -.0006843 _Istate_3 | -.0088063 .0053089 -1.66 0.103 -.0194695 .001857 _Istate_4 | -.0077847 .0040126 -1.94 0.058 -.0158443 .0002748 _Istate_5 | -.0084504 .0027398 -3.08 0.003 -.0139534 -.0029474 _Istate_6 | -.0100656 .003196 -3.15 0.003 -.0164849 -.0036463 _Istate_7 | -.014228 .0046824 -3.04 0.004 -.023633 -.004823 _Istate_8 | -.0094609 .0048581 -1.95 0.057 -.0192187 .000297 _Istate_9 | -.0107791 .0040573 -2.66 0.011 -.0189284 -.0026297 _Istate_10 | -.009097 .0067669 -1.34 0.185 -.0226887 .0044947 _Istate_11 | -.0106959 .0030523 -3.50 0.001 -.0168267 -.0045651 _Istate_12 | -.0106724 .003575 -2.99 0.004 -.017853 -.0034918 _Istate_13 | -.0126377 .005305 -2.38 0.021 -.0232932 -.0019823 _Istate_14 | -.0073945 .0032189 -2.30 0.026 -.0138598 -.0009292 _Istate_15 | -.0114182 .0038587 -2.96 0.005 -.0191686 -.0036677 _Istate_16 | -.0141274 .0042701 -3.31 0.002 -.0227042 -.0055506 _Istate_17 | -.0117984 .0043514 -2.71 0.009 -.0205384 -.0030583 _Istate_18 | -.0122204 .0046016 -2.66 0.011 -.0214631 -.0029777 _Istate_19 | -.0075329 .0032884 -2.29 0.026 -.0141378 -.0009279 _Istate_20 | -.0179998 .0047579 -3.78 0.000 -.0275563 -.0084433 _Istate_21 | -.0108678 .0036149 -3.01 0.004 -.0181285 -.003607 _Istate_22 | -.0159934 .0051506 -3.11 0.003 -.0263388 -.0056481 _Istate_23 | -.0119118 .0038201 -3.12 0.003 -.0195847 -.004239 _Istate_24 | -.0157803 .0038085 -4.14 0.000 -.0234298 -.0081308 _Istate_25 | -.0114279 .0047071 -2.43 0.019 -.0208824 -.0019733 _Istate_26 | -.0061523 .0039693 -1.55 0.127 -.0141248 .0018203 _Istate_27 | -.0087854 .0045463 -1.93 0.059 -.017917 .0003461 _Istate_28 | -.0085751 .0044108 -1.94 0.058 -.0174344 .0002842 _Istate_29 | -.0194209 .0048295 -4.02 0.000 -.0291212 -.0097206 _Istate_30 | -.014221 .0045106 -3.15 0.003 -.0232808 -.0051612 _Istate_31 | -.014161 .003726 -3.80 0.000 -.0216449 -.0066771 _Istate_32 | -.0147025 .0047002 -3.13 0.003 -.0241432 -.0052619 _Istate_33 | -.0054123 .0031929 -1.70 0.096 -.0118256 .0010009 _Istate_34 | -.0033945 .0037189 -0.91 0.366 -.0108642 .0040752 _Istate_35 | -.0106957 .0044915 -2.38 0.021 -.0197172 -.0016742 _Istate_36 | -.0146726 .0044808 -3.27 0.002 -.0236726 -.0056726 _Istate_37 | -.0154988 .0046368 -3.34 0.002 -.0248121 -.0061855 _Istate_38 | -.0099978 .0048078 -2.08 0.043 -.0196545 -.0003411 _Istate_39 | -.0139136 .0056767 -2.45 0.018 -.0253156 -.0025117 _Istate_40 | -.0212217 .0053562 -3.96 0.000 -.0319799 -.0104634 _Istate_41 | -.0073329 .0040999 -1.79 0.080 -.0155677 .0009019 _Istate_42 | -.0128356 .0044655 -2.87 0.006 -.0218047 -.0038664 _Istate_43 | -.0088454 .0046431 -1.91 0.063 -.0181714 .0004805 _Istate_44 | -.0094031 .0025433 -3.70 0.001 -.0145115 -.0042946 _Istate_45 | -.0096562 .0008935 -10.81 0.000 -.0114508 -.0078616 _Istate_46 | -.0131926 .0036813 -3.58 0.001 -.0205867 -.0057986 _Istate_47 | -.0131831 .0042013 -3.14 0.003 -.0216217 -.0047446 _Istate_48 | -.0136453 .0036837 -3.70 0.001 -.0210443 -.0062463 _Istate_49 | -.0152155 .0043274 -3.52 0.001 -.0239074 -.0065236 _Istate_50 | -.0117118 .0062208 -1.88 0.066 -.0242067 .0007831 _Istate_51 | -.00929 .0031968 -2.91 0.005 -.0157109 -.0028691 _cons | .1324191 .0177538 7.46 0.000 .0967596 .1680785 ------------------------------------------------------------------------------ . /* Note that xtreg and xi do not produce the same results. They should. */ . . xi: regress fatalityrate sb_useage speed65 speed70 ba08 drinkage21 ln_inc > age i.state i.year, vce(cluster state) i.state _Istate_1-51 (_Istate_1 for state==AK omitted) i.year _Iyear_1983-1997 (naturally coded; _Iyear_1983 omitted) Linear regression Number of obs = 556 F( 20, 50) = . Prob > F = . R-squared = 0.9098 Root MSE = .00162 (Std. Err. adjusted for 51 clusters in state) ------------------------------------------------------------------------------ | Robust fatalityrate | Coef. Std. Err. t P>|t| [95% Conf. Interval] -------------+---------------------------------------------------------------- sb_useage | -.0037186 .0015246 -2.44 0.018 -.0067808 -.0006563 speed65 | -.0007833 .0006093 -1.29 0.205 -.0020071 .0004405 speed70 | .0008042 .0004803 1.67 0.100 -.0001605 .0017688 ba08 | -.0008225 .0004656 -1.77 0.083 -.0017577 .0001127 drinkage21 | -.0011337 .0006534 -1.74 0.089 -.0024461 .0001787 ln_inc | .0062643 .0070367 0.89 0.378 -.0078693 .0203979 age | .001318 .0007287 1.81 0.076 -.0001455 .0027816 _Istate_2 | -.006243 .0042864 -1.46 0.152 -.0148526 .0023666 _Istate_3 | -.0042506 .0049257 -0.86 0.392 -.0141441 .0056429 _Istate_4 | -.0052045 .0036443 -1.43 0.159 -.0125244 .0021154 _Istate_5 | -.0108974 .0026314 -4.14 0.000 -.0161828 -.005612 _Istate_6 | -.0108515 .0029089 -3.73 0.000 -.0166942 -.0050089 _Istate_7 | -.0221058 .0051785 -4.27 0.000 -.0325071 -.0117044 _Istate_8 | -.0171011 .0052623 -3.25 0.002 -.0276706 -.0065315 _Istate_9 | -.0135796 .0038423 -3.53 0.001 -.021297 -.0058622 _Istate_10 | -.0109605 .0061945 -1.77 0.083 -.0234025 .0014815 _Istate_11 | -.00924 .0027722 -3.33 0.002 -.0148082 -.0036718 _Istate_12 | -.0134439 .0034567 -3.89 0.000 -.0203869 -.006501 _Istate_13 | -.0119732 .0047437 -2.52 0.015 -.0215011 -.0024452 _Istate_14 | -.0031839 .0031233 -1.02 0.313 -.0094574 .0030895 _Istate_15 | -.0136302 .003581 -3.81 0.000 -.0208228 -.0064377 _Istate_16 | -.01306 .0038243 -3.41 0.001 -.0207414 -.0053786 _Istate_17 | -.0116617 .0039143 -2.98 0.004 -.0195238 -.0037997 _Istate_18 | -.0077006 .0042588 -1.81 0.077 -.0162548 .0008535 _Istate_19 | -.0031251 .0032216 -0.97 0.337 -.0095959 .0033456 _Istate_20 | -.0226125 .0047388 -4.77 0.000 -.0321305 -.0130944 _Istate_21 | -.0145783 .003507 -4.16 0.000 -.0216224 -.0075343 _Istate_22 | -.0143826 .0046614 -3.09 0.003 -.0237454 -.0050199 _Istate_23 | -.0123339 .0034336 -3.59 0.001 -.0192304 -.0054374 _Istate_24 | -.0169814 .003445 -4.93 0.000 -.0239008 -.010062 _Istate_25 | -.0106489 .004242 -2.51 0.015 -.0191692 -.0021286 _Istate_26 | .0013805 .0041246 0.33 0.739 -.006904 .009665 _Istate_27 | -.0054104 .0041902 -1.29 0.203 -.0138267 .0030059 _Istate_28 | -.0075154 .0039383 -1.91 0.062 -.0154257 .000395 _Istate_29 | -.0152857 .0044524 -3.43 0.001 -.0242286 -.0063428 _Istate_30 | -.0131598 .0040601 -3.24 0.002 -.0213147 -.005005 _Istate_31 | -.0169859 .0035462 -4.79 0.000 -.0241087 -.0098631 _Istate_32 | -.0209118 .0049428 -4.23 0.000 -.0308398 -.0109838 _Istate_33 | -.000588 .0031653 -0.19 0.853 -.0069456 .0057696 _Istate_34 | -.0049867 .0034257 -1.46 0.152 -.0118674 .0018939 _Istate_35 | -.0156315 .0044918 -3.48 0.001 -.0246536 -.0066094 _Istate_36 | -.0147419 .0040165 -3.67 0.001 -.0228094 -.0066745 _Istate_37 | -.0119849 .0042589 -2.81 0.007 -.0205392 -.0034307 _Istate_38 | -.0102034 .0043233 -2.36 0.022 -.018887 -.0015198 _Istate_39 | -.0157842 .0053463 -2.95 0.005 -.0265225 -.005046 _Istate_40 | -.0224869 .0050609 -4.44 0.000 -.0326521 -.0123217 _Istate_41 | -.0033727 .0038123 -0.88 0.381 -.0110299 .0042844 _Istate_42 | -.0089397 .004125 -2.17 0.035 -.0172251 -.0006544 _Istate_43 | -.0071673 .0041736 -1.72 0.092 -.0155502 .0012156 _Istate_44 | -.0076143 .0022887 -3.33 0.002 -.0122113 -.0030174 _Istate_45 | -.0035202 .0019423 -1.81 0.076 -.0074214 .0003809 _Istate_46 | -.0151335 .0033838 -4.47 0.000 -.02193 -.0083369 _Istate_47 | -.0125393 .0037681 -3.33 0.002 -.0201077 -.0049708 _Istate_48 | -.0149413 .0033425 -4.47 0.000 -.0216549 -.0082277 _Istate_49 | -.014876 .0038718 -3.84 0.000 -.0226527 -.0070993 _Istate_50 | -.0071627 .005718 -1.25 0.216 -.0186477 .0043223 _Istate_51 | -.0072928 .0028862 -2.53 0.015 -.0130899 -.0014957 _Iyear_1984 | -.0004319 .0014475 -0.30 0.767 -.0033392 .0024754 _Iyear_1985 | -.0010707 .001853 -0.58 0.566 -.0047925 .0026512 _Iyear_1986 | -.0005777 .002109 -0.27 0.785 -.0048138 .0036583 _Iyear_1987 | -.0008722 .0026195 -0.33 0.741 -.0061336 .0043892 _Iyear_1988 | -.001885 .0030219 -0.62 0.536 -.0079547 .0041847 _Iyear_1989 | -.0041766 .0034205 -1.22 0.228 -.0110468 .0026936 _Iyear_1990 | -.005266 .0037186 -1.42 0.163 -.012735 .0022031 _Iyear_1991 | -.0066622 .0039487 -1.69 0.098 -.0145935 .001269 _Iyear_1992 | -.008518 .0041863 -2.03 0.047 -.0169265 -.0001095 _Iyear_1993 | -.0089399 .0044105 -2.03 0.048 -.0177988 -.0000811 _Iyear_1994 | -.0096297 .0048249 -2.00 0.051 -.0193207 .0000613 _Iyear_1995 | -.0101123 .0051428 -1.97 0.055 -.0204419 .0002172 _Iyear_1996 | -.0110766 .0054713 -2.02 0.048 -.022066 -.0000871 _Iyear_1997 | -.0116075 .0058129 -2.00 0.051 -.0232831 .0000681 _cons | -.0668073 .0691961 -0.97 0.339 -.2057918 .0721772 ------------------------------------------------------------------------------ . testparm _Iyear* ( 1) _Iyear_1984 = 0 ( 2) _Iyear_1985 = 0 ( 3) _Iyear_1986 = 0 ( 4) _Iyear_1987 = 0 ( 5) _Iyear_1988 = 0 ( 6) _Iyear_1989 = 0 ( 7) _Iyear_1990 = 0 ( 8) _Iyear_1991 = 0 ( 9) _Iyear_1992 = 0 (10) _Iyear_1993 = 0 (11) _Iyear_1994 = 0 (12) _Iyear_1995 = 0 (13) _Iyear_1996 = 0 (14) _Iyear_1997 = 0 F( 14, 50) = 8.90 Prob > F = 0.0000 . scalar sb_effect = _b[sb_useage] . . summarize sb_useage fatalityrate Variable | Obs Mean Std. Dev. Min Max -------------+-------------------------------------------------------- sb_useage | 556 .5288518 .1701859 .06 .87 fatalityrate | 765 .0214895 .0061713 .0083273 .0454701 . . scalar d_fr = sb_effect*0.38 . scalar list d_fr d_fr = -.00141305 . . /* Get the total vehicle miles for 1997 > Here I multiply the average times the number of states */ . summarize vmt if year == 1997 Variable | Obs Mean Std. Dev. Min Max -------------+-------------------------------------------------------- vmt | 51 50203.37 51775.3 3326 285612 . scalar miles = 51*r(mean) . . scalar lives_saved = miles * d_fr . scalar list lives_saved miles lives_saved = -3617.9379 miles = 2560372 . di "The fatalities change by approximately " lives_saved " The fatalities change by approximately -3617.9379 . di "Based on an estimated " miles " miles of highway in the US in 1997." Based on an estimated 2560372 miles of highway in the US in 1997. . . /* First, run the regression and determine how much sb usage increases > ** when switching between secondary to primary enforcement. Then > ** multiply this times the seat belt effect in the fatality rate regression. > */ . xi: regress sb_useage primary secondary speed65 speed70 ba08 drinkage21 ln_i > nc age i.year i.state, vce(cluster state) i.year _Iyear_1983-1997 (naturally coded; _Iyear_1983 omitted) i.state _Istate_1-51 (_Istate_1 for state==AK omitted) Linear regression Number of obs = 556 F( 21, 50) = . Prob > F = . R-squared = 0.9016 Root MSE = .05722 (Std. Err. adjusted for 51 clusters in state) ------------------------------------------------------------------------------ | Robust sb_useage | Coef. Std. Err. t P>|t| [95% Conf. Interval] -------------+---------------------------------------------------------------- primary | .2055968 .0243489 8.44 0.000 .1566907 .254503 secondary | .1085184 .0140858 7.70 0.000 .0802262 .1368106 speed65 | .0228485 .0215529 1.06 0.294 -.0204417 .0661388 speed70 | .0120424 .0216313 0.56 0.580 -.0314054 .0554902 ba08 | .0037584 .018507 0.20 0.840 -.033414 .0409307 drinkage21 | .0107149 .0285425 0.38 0.709 -.0466144 .0680442 ln_inc | .0582708 .269387 0.22 0.830 -.482809 .5993506 age | .0138232 .0243016 0.57 0.572 -.034988 .0626345 _Iyear_1984 | .0041178 .0299885 0.14 0.891 -.0561159 .0643514 _Iyear_1985 | .0575169 .0452117 1.27 0.209 -.0332935 .1483273 _Iyear_1986 | .1073527 .0579004 1.85 0.070 -.0089437 .223649 _Iyear_1987 | .1240647 .0810099 1.53 0.132 -.0386485 .2867779 _Iyear_1988 | .1390924 .1025384 1.36 0.181 -.0668621 .3450468 _Iyear_1989 | .1702325 .1186812 1.43 0.158 -.0681457 .4086106 _Iyear_1990 | .1897753 .1358066 1.40 0.168 -.0830004 .462551 _Iyear_1991 | .2370697 .143986 1.65 0.106 -.0521347 .5262741 _Iyear_1992 | .2633971 .1598977 1.65 0.106 -.057767 .5845612 _Iyear_1993 | .2824192 .1717693 1.64 0.106 -.0625896 .6274279 _Iyear_1994 | .2983722 .1826111 1.63 0.109 -.0684131 .6651575 _Iyear_1995 | .2959081 .1946357 1.52 0.135 -.0950292 .6868454 _Iyear_1996 | .2875641 .2086531 1.38 0.174 -.1315281 .7066562 _Iyear_1997 | .2977352 .2209318 1.35 0.184 -.1460193 .7414896 _Istate_2 | -.1756765 .137504 -1.28 0.207 -.4518615 .1005084 _Istate_3 | -.2221958 .1558769 -1.43 0.160 -.5352837 .0908921 _Istate_4 | -.084915 .1180764 -0.72 0.475 -.3220784 .1522483 _Istate_5 | -.0164859 .0931025 -0.18 0.860 -.2034878 .170516 _Istate_6 | -.1905976 .0966401 -1.97 0.054 -.384705 .0035098 _Istate_7 | -.1896531 .1833995 -1.03 0.306 -.5580219 .1787157 _Istate_8 | -.1973043 .1925661 -1.02 0.310 -.5840846 .189476 _Istate_9 | -.1280651 .1325492 -0.97 0.339 -.394298 .1381677 _Istate_10 | -.1791013 .2064862 -0.87 0.390 -.593841 .2356385 _Istate_11 | -.2017399 .0890463 -2.27 0.028 -.3805946 -.0228852 _Istate_12 | .0233767 .1151764 0.20 0.840 -.2079619 .2547152 _Istate_13 | -.1415345 .1559403 -0.91 0.368 -.4547497 .1716808 _Istate_14 | -.2043592 .1003289 -2.04 0.047 -.4058757 -.0028428 _Istate_15 | -.1522498 .1225744 -1.24 0.220 -.3984477 .0939481 _Istate_16 | -.1673752 .1228003 -1.36 0.179 -.4140268 .0792764 _Istate_17 | -.1465226 .1286498 -1.14 0.260 -.4049233 .1118782 _Istate_18 | -.2186984 .1346072 -1.62 0.111 -.489065 .0516682 _Istate_19 | -.18281 .1027128 -1.78 0.081 -.3891147 .0234946 _Istate_20 | -.2437102 .1647207 -1.48 0.145 -.5745616 .0871412 _Istate_21 | -.0501152 .1254506 -0.40 0.691 -.3020902 .2018598 _Istate_22 | -.2430171 .1508651 -1.61 0.114 -.5460385 .0600043 _Istate_23 | -.1046723 .1132926 -0.92 0.360 -.3322272 .1228827 _Istate_24 | -.1682314 .1154668 -1.46 0.151 -.4001533 .0636906 _Istate_25 | -.1099258 .1389826 -0.79 0.433 -.3890806 .1692289 _Istate_26 | -.3492719 .1343077 -2.60 0.012 -.6190369 -.079507 _Istate_27 | -.0477431 .1334271 -0.36 0.722 -.3157392 .2202531 _Istate_28 | -.099044 .1300936 -0.76 0.450 -.3603447 .1622566 _Istate_29 | -.3091931 .1413721 -2.19 0.033 -.5931473 -.0252388 _Istate_30 | -.1548124 .1322405 -1.17 0.247 -.4204253 .1108005 _Istate_31 | -.1074939 .1225906 -0.88 0.385 -.3537243 .1387365 _Istate_32 | -.1571154 .1732687 -0.91 0.369 -.5051357 .1909049 _Istate_33 | -.0478893 .1122414 -0.43 0.671 -.2733327 .1775541 _Istate_34 | -.1326597 .1167591 -1.14 0.261 -.3671774 .1018579 _Istate_35 | -.1241203 .1558014 -0.80 0.429 -.4370567 .1888161 _Istate_36 | -.1489693 .1313673 -1.13 0.262 -.4128282 .1148897 _Istate_37 | -.2843925 .134892 -2.11 0.040 -.5553312 -.0134539 _Istate_38 | -.0760239 .1434907 -0.53 0.599 -.3642334 .2121855 _Istate_39 | -.1118006 .173708 -0.64 0.523 -.4607035 .2371022 _Istate_40 | -.2790959 .1624797 -1.72 0.092 -.605446 .0472542 _Istate_41 | -.1490303 .121125 -1.23 0.224 -.392317 .0942564 _Istate_42 | -.2696659 .1327644 -2.03 0.048 -.5363311 -.0030007 _Istate_43 | -.1654254 .1335338 -1.24 0.221 -.4336359 .1027851 _Istate_44 | -.0990137 .0805916 -1.23 0.225 -.2608868 .0628593 _Istate_45 | -.1416552 .0845265 -1.68 0.100 -.3114317 .0281212 _Istate_46 | -.0639255 .1147761 -0.56 0.580 -.2944601 .166609 _Istate_47 | -.1309635 .1230899 -1.06 0.292 -.3781969 .1162699 _Istate_48 | -.024428 .1136688 -0.21 0.831 -.2527385 .2038825 _Istate_49 | -.1284356 .1260573 -1.02 0.313 -.3816291 .1247579 _Istate_50 | -.2030722 .1818654 -1.12 0.269 -.5683595 .1622151 _Istate_51 | -.0781333 .0938978 -0.83 0.409 -.2667325 .1104659 _cons | -.747934 2.7482 -0.27 0.787 -6.267856 4.771988 ------------------------------------------------------------------------------ . scalar chg = _b[primary]-_b[secondary] . scalar effect = chg*sb_effect . . /* Finally, get the vehicle miles for NJ in 2000. > ** Since this is not available, I use 1997 data. > ** In 1997 there are about 63300 miles in NJ > */ . summarize vmt if state == "NJ" & year == 1997 Variable | Obs Mean Std. Dev. Min Max -------------+-------------------------------------------------------- vmt | 1 63308 . 63308 63308 . scalar NJ_effect = r(mean)*effect . scalar list chg effect NJ_effect chg = .09707843 effect = -.00036099 NJ_effect = -22.853661 . . di "The switch has a estimated effect of " NJ_effect " on fatalities in New J > ersey" The switch has a estimated effect of -22.853661 on fatalities in New Jersey . end of do-file . log close log: C:\Temp\web\class\5213\2008\HW_E10.2.log log type: text closed on: 25 Nov 2008, 12:10:40 -------------------------------------------------------------------------------