Mike: Chapt 3, #10 and #11

Below is my do file that I created. If you copy the code and put it in notepad and then save it with a .do extention, you should be able to run the whole code at once. You will need to the change the first line so that the file knows where the dataset is stored.

use E:\BiostatsII\3.ex.funding.dta
*Questions 10 and 11*Perform influence analyses on the other covariates in the model from question 6.
generate log_dol = log( dollars)
generate log_mort = log(mort)
generate log_yrs = log(yrslost)
generate log_hosp = log(hospdays)
generate log_disabil = log(disabil)
regress log_dol log_hosp log_mort log_yrs log_disabil
predict h, leverage
predict z, rstandard
predict t, rstudent
predict deltab1, dfbeta(log_mort)
predict cook1, cooksd
list id disease h z t deltab1 cook1 if deltab1 >.5 deltab1 <-.5
predict deltab2, dfbeta(log_yrs)
predict cook2, cooksd
list id disease h z t deltab2 cook2 if deltab2 >.5 deltab2 <-.5
predict deltab3, dfbeta(log_hosp)
predict cook3, cooksd
list id disease h z t deltab3 cook3 if deltab3 >.5 deltab3 <-.5
*I didn’t remove peptic ulcers because the cook score was so very low; a cook score that warrants examination is .276 and peptic ulcers had .131 cook score.
predict deltab4, dfbeta(log_disabil)
predict cook4, cooksd
list id disease h z t deltab4 cook4 if deltab4 >.5 deltab4 <-.5
* Regress log[dollars] against log[disabil] and log[hospdays].
regress log_dol log_hosp log_disabil
editpreserveset obs 30replace id = 99 in 30replace hospdays = 1000 in 30replace disabil = 1000 in 30
replace log_hosp=log(hospdays) if id==99
replace log_disabil=log(disabil) if id==99
predict yhat1, xb
predict h1, leverage
predict std_yhat1, stdp
predict std_f1, stdf
generate cil_yhat1= yhat1 -invttail(29-2-1, .025)*std_yhat1
generate ciu_yhat1= yhat1 + invttail(29-2-1, .025)*std_yhat1
generate cil_f1 = yhat1 - invttail(29-2-1,.025)*std_f1
generate ciu_f1 = yhat1 + invttail(29-2-1,.025)*std_f1
generate pred_dollars= exp(yhat1)
generate cil_dollarsf1 = exp(cil_f1)
generate ciu_dollarsf1 = exp(ciu_f1)
generate cil_dollarsp1 = exp(cil_yhat1)
generate ciu_dollarsp1 = exp(ciu_yhat1)
list hospdays disabil pred_dollars cil_dollarsp1 ciu_dollarsp1 cil_dollarsf1 ciu_dollarsf1 if id==99