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       log:  /Volumes/fmwww0/cfb/stata/levpredict.smcl
  log type:  smcl
 opened on:   4 Feb 2009, 10:53:15


. // dataset from MUS ch3 . use http://fmwww.bc.edu/cfb/stata/mus03data, clear

. . su totexp ltotexp if totexp > 0, detail

Total medical expenditure ------------------------------------------------------------- Percentiles Smallest 1% 81 3 5% 300 6 10% 581 9 Obs 2955 25% 1433 14 Sum of Wgt. 2955

50% 3334 Mean 7290.235 Largest Std. Dev. 11990.84 75% 7497 104823 90% 17549 108256 Variance 1.44e+08 95% 27941 123611 Skewness 4.113807 99% 62989 125610 Kurtosis 25.64123

ln(totexp) if totexp > 0 ------------------------------------------------------------- Percentiles Smallest 1% 4.394449 1.098612 5% 5.703783 1.791759 10% 6.364751 2.197225 Obs 2955 25% 7.267525 2.639057 Sum of Wgt. 2955

50% 8.111928 Mean 8.059866 Largest Std. Dev. 1.367592 75% 8.922258 11.56003 90% 9.772752 11.59225 Variance 1.870308 95% 10.23785 11.72489 Skewness -.3857887 99% 11.05072 11.74094 Kurtosis 3.842263

. . reg ltotexp suppins phylim actlim totchr age female income

Source | SS df MS Number of obs = 2955 -------------+------------------------------ F( 7, 2947) = 124.98 Model | 1264.72124 7 180.674463 Prob > F = 0.0000 Residual | 4260.16814 2947 1.44559489 R-squared = 0.2289 -------------+------------------------------ Adj R-squared = 0.2271 Total | 5524.88938 2954 1.87030785 Root MSE = 1.2023

------------------------------------------------------------------------------ ltotexp | Coef. Std. Err. t P>|t| [95% Conf. Interval] -------------+---------------------------------------------------------------- suppins | .2556428 .0462264 5.53 0.000 .1650034 .3462821 phylim | .3020598 .0569709 5.30 0.000 .190353 .4137666 actlim | .3560054 .0621118 5.73 0.000 .2342185 .4777923 totchr | .3758201 .0184227 20.40 0.000 .3396974 .4119429 age | .0038016 .0036561 1.04 0.299 -.0033672 .0109705 female | -.0843275 .0455442 -1.85 0.064 -.1736292 .0049741 income | .0025498 .0010194 2.50 0.012 .000551 .0045486 _cons | 6.703737 .27676 24.22 0.000 6.161075 7.2464 ------------------------------------------------------------------------------

. . levpredict tenorm, print

Prediction of exp(ltotexp) from command: regress created as variable: tenorm

Mean level prediction ignoring E[exp(U_i)] = 4004.4529

Bias in mean level prediction: -4245.4746

. levpredict teduan, duan print

Prediction of exp(ltotexp) from command: regress created as variable: teduan using method of Duan, assuming i.i.d. errors

Mean level prediction ignoring E[exp(U_i)] = 4004.4529

Bias in mean level prediction: -4001.0692

. . su totexp ltotexp tenorm teduan if totexp > 0

Variable | Obs Mean Std. Dev. Min Max -------------+-------------------------------------------------------- totexp | 2955 7290.235 11990.84 3 125610 ltotexp | 2955 8.059866 1.367592 1.098612 11.74094 tenorm | 2955 8249.928 6805.945 1976.955 77723.15 teduan | 2955 8005.522 6604.318 1918.388 75420.59

. . // qui reg totexp suppins phylim actlim totchr age female income . // levpredict testerr . . log close log: /Volumes/fmwww0/cfb/stata/levpredict.smcl log type: smcl closed on: 4 Feb 2009, 10:53:19 -------------------------------------------------------------------------------------------