/* Produce Confidence Intervals p. 60 */
quietly {
 log using confint, smcl replace
 regress sbp age

 predict se_ci, stdp                       /* SE for confidence interval around Y */
 predict se_pi, stdf                       /* SE for prediction interval around Y */
 predict yhat, xb                          /* Predicted or expected values        */

 display invttail(e(df_r),(.05/2))         /* Determine t-critical                */

 generate ll_ci=yhat-(se_ci*2.0484071)     /* Create the lower and upper limits   */
 generate ul_ci=yhat+(se_ci*2.0484071)

 generate ll_pi=yhat-(se_pi*2.0484071)
 generate ul_pi=yhat+(se_pi*2.0484071)
 format sbp yhat se_ci ll_ci ul_ci ll_pi ul_pi %9.4f

 noisily di _n "Inferences ABout the Regression Line (pp. 59-61)"
 noisily di _n "Regression of SBP(Y) on Age (X)"
 noisily list id sbp yhat se_ci ll_ci ul_ci ll_pi ul_pi, noobs /* What does it look like?  pp. 58-59 */
 drop se_ci- ul_pi
 log close
 view confint.smcl
}