Oil Wildcatter's Problem with an Insurance (dtree1)
/****************************************************************/
/* S A S S A M P L E L I B R A R Y */
/* */
/* NAME: DTREE1 */
/* TITLE: Oil Wildcatter's Problem with an Insurance (dtree1) */
/* PRODUCT: OR */
/* SYSTEM: ALL */
/* KEYS: DTREE */
/* PROCS: DTREE, PRINT */
/* DATA: */
/* */
/* SUPPORT: UPDATE: */
/* REF: Example 1 from the DTREE chapter */
/* MISC: */
/* */
/****************************************************************/
/* -- create the STAGEIN= data set -- */
data Dtoils4;
format Stage $12. Stype $2. Outcome $14.
Succ $12. Premium dollar12.0;
input Stage $12. Stype $4. Outcome $16. Succ $12.
Premium dollar12.0;
datalines;
Drill D Drill Insurance .
. . Not_Drill . .
Insurance D Buy_Insurance Cost -$130,000
. . Do_Not_Buy Cost .
Cost C Low Oil_Deposit .
. . Fair Oil_Deposit .
. . High Oil_Deposit .
Oil_Deposit C Dry . .
. . Wet . .
. . Soaking . .
;
/* -- create the PROBIN= data set -- */
data Dtoilp4;
input (V1-V3) ($) P1-P3 ;
datalines;
Low Fair High 0.2 0.6 0.2
Dry Wet Soaking 0.5 0.3 0.2
;
/* -- create PAYOFFS= data set -- */
data Dtoilu4;
input (Cost Deposit Drill Insuran) ($16.) ;
format Drill $9. Insuran $14. Payoff dollar12.0;
/* determine the cost for this scenario */
if Cost='Low' then Rcost=150000;
else if Cost='Fair' then Rcost=300000;
else Rcost=500000;
/* determine the oil deposit and the corresponding */
/* net payoff for this scenario */
if Deposit='Dry' then Return=0;
else if Deposit='Wet' then Return=700000;
else Return=1200000;
/* calculate the net return for this scenario */
if Drill='Not_Drill' then Payoff=0;
else Payoff=Return-Rcost;
/* determine redeem received for this scenario */
if Insuran='Buy_Insurance' and Deposit='Dry' then
Payoff=Payoff+200000;
/* drop unneeded variables */
drop Rcost Return;
datalines;
Low Dry Not_Drill .
Low Dry Drill Buy_Insurance
Low Dry Drill Do_Not_Buy
Low Wet Not_Drill .
Low Wet Drill Buy_Insurance
Low Wet Drill Do_Not_Buy
Low Soaking Not_Drill .
Low Soaking Drill Buy_Insurance
Low Soaking Drill Do_Not_Buy
Fair Dry Not_Drill .
Fair Dry Drill Buy_Insurance
Fair Dry Drill Do_Not_Buy
Fair Wet Not_Drill .
Fair Wet Drill Buy_Insurance
Fair Wet Drill Do_Not_Buy
Fair Soaking Not_Drill .
Fair Soaking Drill Buy_Insurance
Fair Soaking Drill Do_Not_Buy
High Dry Not_Drill .
High Dry Drill Buy_Insurance
High Dry Drill Do_Not_Buy
High Wet Not_Drill .
High Wet Drill Buy_Insurance
High Wet Drill Do_Not_Buy
High Soaking Not_Drill .
High Soaking Drill Buy_Insurance
High Soaking Drill Do_Not_Buy
;
/* -- print the payoff table -- */
title "Oil Wildcatter's Problem";
title3 "The Payoffs";
proc print data=Dtoilu4;
run;
/* -- PROC DTREE statements -- */
title "Oil Wildcatter's Problem";
proc dtree stagein=Dtoils4
probin=Dtoilp4
payoffs=Dtoilu4
nowarning
;
variables / stage=Stage type=Stype outcome=(Outcome)
reward=(Premium) successor=(Succ)
event=(V1 V2 V3) prob=(P1 P2 P3)
state=(Cost Deposit Drill Insuran)
payoff=(Payoff);
evaluate;
summary / target=Insurance;
reset criterion=maxce rt=1200000;
summary / target=Insurance;
quit;
/* -- clear up -- */
title ;