/*-----------------------------------------------------------------
            S A S   S A M P L E   L I B R A R Y                   
                                                                  
      NAME: pwrex09                                               
     TITLE: Documentation Example 9 for PROC POWER                
            (Binary Logistic Regression with Independent          
            Predictors)                                           
   PRODUCT: STAT                                                  
    SYSTEM: ALL                                                   
      KEYS: power                                                 
            sample size                                           
            power analysis                                        
     PROCS: POWER                                                 
      DATA:                                                       
                                                                  
   SUPPORT: John Castelloe                                        
       REF:                                                       
      MISC:                                                       
-----------------------------------------------------------------*/

proc power;
   logistic
      vardist("Heat") = ordinal((5 10 15 20) : (0.2 0.3 0.3 0.2))
      vardist("Soak") = ordinal((2 4 6) : (0.4 0.4 0.2))
      vardist("Mass1") = normal(4, 1)
      vardist("Mass2") = normal(4, 2)
      testpredictor = "Heat"
      covariates = "Soak" | "Mass1" "Mass2"
      responseprob = 0.15 0.25
      testoddsratio = 1.2
      units= ("Heat" = 5)
      covoddsratios = 1.4 | 1 1.3
      alpha = 0.1
      power = 0.9
      ntotal = .;
run;