DATA LIST   FREE RECORDS=1/ bx  bz  bxZ MEANX MEANZ                    
     SDX SDZ sdy CONSTANT VARXX VARXXZ COVXZXZ.                                      
COMPUTE  LOWZLOWX=(bx+(bxZ*-SDZ))*(-SDX)+((bz*-SDZ)+CONSTANT).          
COMPUTE  LOWZMEDX=(bx+(bxZ*-SDZ))*(MEANX)+((bz*-SDZ)+CONSTANT).         
COMPUTE  LOWZHIX=(bx+(bxZ*-SDZ))*(SDX)+((bz*-SDZ)+CONSTANT).            
COMPUTE  MEDZLOWX=(bx+(bxZ*MEANZ))*(-SDX)+((bz*MEANZ)+CONSTANT).        
COMPUTE  MEDZMEDX=(bx+(bxZ*MEANZ))*(MEANX)+((bz*MEANZ)+CONSTANT).       
COMPUTE  MEDZHIX=(bx+(bxZ*MEANZ))*(SDX)+((bz*MEANZ)+CONSTANT).          
COMPUTE  HIZLOWX=(bx+(bxZ*SDZ))*(-SDX)+((bz*SDZ)+CONSTANT).             
COMPUTE  HIZMEDX=(bx+(bxZ*SDZ))*(MEANX)+((bz*SDZ)+CONSTANT).            
COMPUTE  HIZHIX=(bx+(bxZ*SDZ))*(SDX)+((bz*SDZ)+CONSTANT).               
COMPUTE  LOWZSLOP=bx+(bxZ*-SDZ).                                           
COMPUTE  MEDZSLOP=bx+(bxZ*MEANZ).                                          
COMPUTE  HIZSLOP=bx+(bxZ*SDZ).                                             
COMPUTE  ERRSLP1=SQRT(VARXX+(2*(-SDZ)*(VARXXZ))+(-SDZ*-SDZ)*COVXZXZ).            
COMPUTE  ERRSLP2=SQRT(VARXX+(2*(MEANZ)*(VARXXZ))+(MEANZ*MEANZ)*COVXZXZ).         
COMPUTE  ERRSLP3=SQRT(VARXX+(2*(SDZ)*(VARXXZ))+(SDZ*SDZ)*COVXZXZ).   
            
COMPUTE  STANSLP1=LOWZSLOP*(SDX/SDY).
COMPUTE  STANSLP2=MEDZSLOP*(SDX/SDY).
COMPUTE  STANSLP3=HIZSLOP*(SDX/SDY).
COMPUTE  TSLOPE1=LOWZSLOP/ERRSLP1.
COMPUTE  TSLOPE2=MEDZSLOP/ERRSLP2.                                              
COMPUTE  TSLOPE3=HIZSLOP/ERRSLP3.                                                

BEGIN DATA.
.005936 .312 .00003525 .001961 -.0099804 4245.9222 31.7249 17.204 52.173 .0000001647 .000000002282 .0000000002317
END DATA.

LIST  VARIABLES=LOWZLOWX LOWZHIX HIZLOWX HIZHIX.
LIST VARS=LOWZSLOP HIZSLOP ERRSLP1 ERRSLP3 STANSLP1 STANSLP3.
LIST VARS=TSLOPE1 TSLOPE3.

Note: BX, BZ, and BXZ are the unstandardized regression coefficients for the first predictor variable, the second predictor variable, and the interaction term, respectively.  MEANX and MEANZ are the means, and SDX, SDZ, and SDY are the standard deviations. CONSTANT is the constant or intercept value.  VARXX is the estimated variance of the regression coefficient for the continuous predictor.  VARXZXZ is the estimated variance of the regression coefficient for the interaction term (from the diagonal of the bcov matrix.  COVXXZ is the estimated covariance between the first predictor slope (b for X variable) and the interaction term slope (b for XZ). The program prints out the plot points for plotting two simple slope regression lines (LOWZLOWX LOWZHIX, HIZLOWX, HIZHIX), unstandardized slope estimates (LOWZSLOP, HIZSLOP), their standard errors (ERRSLP1,ERRSLP3), standardized slopes (STANSLP1, STANSLP3), and the t-tests for the coefficients (TSLOPE1, TSLOPE3).  To test simple slopes when the Z predictor is dummy coded: replace –SDX with 0 and SDX with 1 in the first set of compute statements.  To test simple slopes when an unweighted effect code is used: replace –SDX with –1 and SDX with 1 in the first set of compute statements.  To test simple slopes with weighted effect codes: replace –SDX with –P1/Pother and SDX with 1.  P1 is the proportion of the sample coded 1 under effect or dummy coding, and Pother is the proportion in the other group (coded 0 in dummy coding or –1 in effect coding).