/*-----------------------------------------------------------------
            S A S   S A M P L E   L I B R A R Y                   
                                                                  
      NAME: SEQDX11                                               
     TITLE: Documentation Example 11 for PROC SEQDESIGN           
   PRODUCT: STAT                                                  
    SYSTEM: ALL                                                   
      KEYS: group sequential design                               
     PROCS: SEQDESIGN                                             
      DATA:                                                       
                                                                  
   SUPPORT: Yang Yuan             UPDATE: Aug 21, 2007            
       REF: PROC SEQDESIGN, EXAMPLE 11                            
      MISC:                                                       
-----------------------------------------------------------------*/

ods graphics on;
proc seqdesign altref=1.0
               pss(cref=0 0.5 1)
               stopprob(cref=0 0.5 1)
               errspend
               plots=(asn power errspend)
               ;

   TwoSidedErrorSpending: design nstages=3
                          method(upperalpha)=errfuncpow(rho=3)
                          method(loweralpha)=errfuncpow(rho=1)
                          info=cum(2 3 4)
                          alt=twosided
                          stop=reject
                          alpha=0.075(upper=0.025)
                          ;
run;