data outpow2; set outpow; 
output; z=root1; root1=root2; root2=z; drop z; output; 
proc gplot; plot root1*root2; run; 
data grid; 
 do root1 = 0 to 1 by .025; do root2 = 0 to 1 by .025; 
 output; end; end; 
data all; set outpow2 grid; 
Ltau = log(ptau/(1-ptau));   Lrho=log(prho/(1-prho)); 
Ltau_M = log(ptau_M/(1-ptau_M));Lrho_M=log(prho_M/(1-prho_M));
Ltau_t = log(ptau_t/(1-ptau_t));Lrho_t=log(prho_t/(1-prho_t));
r12 = root1*root2; 
proc reg; model ltau lrho ltau_m lrho_M ltau_t lrho_t
= root1 root2 r12; 
output out=outlog p=pptau pprho pptau_M pprho_M pptau_t pprho_t; 
where min(root1,root2)>.5;
data convert; 
set outlog; 
pptau = exp(pptau)/(1+exp(pptau)); 
pprho = exp(pprho)/(1+exp(pprho));
pptau_M = exp(pptau_M)/(1+exp(pptau_M));
pprho_M = exp(pprho_M)/(1+exp(pprho_M));
pptau_t = exp(pptau_t)/(1+exp(pptau_t));
pprho_t = exp(pprho_t)/(1+exp(pprho_t));
proc g3d; plot root1*root2=pprho/zmax=1 zmin=.05; where ltau=.;
label pprho="Rho  ";
proc g3d; plot root1*root2=pptau/zmax=1 zmin=.05; where ltau=.;
label pptau="Tau  ";
proc g3d; plot root1*root2=pprho_M/zmax=1 zmin=.05; where ltau=.;
label pprho_M="Rho_M";
proc g3d; plot root1*root2=pptau_M/zmax=1 zmin=.05; where ltau=.;
label pptau_M="Tau_M";
proc g3d; plot root1*root2=pprho_t/zmax=1 zmin=.05; where ltau=.;
label pprho_t="Rho_t";
proc g3d; plot root1*root2=pptau_t/zmax=1 zmin=.05; where ltau=.;
label pptau_t="Tau_t";
run; quit;