[help!]How to delete an equation?

Dynare help (legacy posts)
#1

Hello everybody,I’m a beginner to use dynare and make dsge model.

I’ve just made a model like follows:

var zco zy obsy c zc lamd zl l w co2 q zi rk nr p m zm r i ld kd yd pcer ad lc kc ac k yc y pai psd psc g M;

varexo ey ec el ei eco em ead eac eM eg er;

parameters rouy nrss rss rkss ycss ydss wss lamdss kss ldss iss yss css gss pss psdss pscss sigc sigl sigco delta sigm roui rouc roul rouco roum a b cc ebip beta lamdf lamdk lamdl gama rouad rouac rouM roug phim phiy;

model ;
zc-sigcc=lamd;
zl-sigll=lamd+w;
q=-zi;
zco-sigcoco2=lamd+pcer;
q=pai(+1)-(nr/(1+nrss))+(((1-delta)q(+1)+rkssrk(+1))/(1-delta+rkss));
zm-sigmm=lamd+nr/(1+nrss);
zi=rouizi(-1)+ei;
zc=rouczc(-1)+ec;
zm=roumzm(-1)+em;
zl=roulzl(-1)+el;
zco=rouco*zco(-1)+eco;

rk+kd(-1)=ark+bw+(1-a-b)pcer-ad+yd;
w+ld=ar+bw+(1-a-b)pcer-ad+yd;
pcer+co2=ar+bw+(1-a-b)pcer-ad+yd;
rk+kc(-1)=ccrk+(1-cc)w-ac+yc;
w+lc=ccr+(1-cc)w-ac+yc;
yc=ac+cclc+(1-cc)kc(-1);
yd=ad+ald+bkd(-1)+(1-a-b)co2;
yssy=(gama^(1/lamdf))(ydss^((lamdf-1)/lamdf))yd+((1-gama)^(1/lamdf))(ydss^((lamdf-1)/lamdf))yc;
ad=rouadad(-1)+ead;
ac=rouacac(-1)+eac;
psd=(1-ebipbeta)(ark+bw+(1-a-b)pcer-ad)+ebipbeta((pss^(1-lamdf))(pai(+1)+p)+(1-gama)(pscss^(1-lamdf))(yc(+1)+yd(+1))/lamdf)/(gama(psdss^(1-lamdf))+(1-gama)(pscss^(1-lamdf)))+pai;
psc=(1-ebipbeta)(ccrk+(1-cc)w-ac)+ebipbeta*((pss^(1-lamdf))(pai(+1)+p)+(1-gama)(pscss^(1-lamdf))(yc(+1)+yd(+1))/lamdf)/(gama(psdss^(1-lamdf))+(1-gama)(pscss^(1-lamdf)))-(1/lamdf)(yc(+1)+yd(+1))+pai;
(pss^(1-lamdf))p=gama(psdss^(1-lamdf))psd+(1-gama)(pscss^(1-lamdf))*psc;

M=rouMM(-1)+eM;
g=rougg(-1)+eg;
m=M-p;
k=lamdkkd+(1-lamdk)kc;
l=lamdlld+(1-lamdl)lc;
r(+1)=phimr+(1-phim)phiyy(+1)+er;
y=issi/yss+cssc/yss+gssg/yss;
r=nr-pai(+1);
rk=r+delta;
k=(1-delta)k(-1)+delta(i+zi);
obsy=yzy;
zy=rouyzy(-1)+ey;
end;

But the number of the endogenous variables is more than equations.Which equation should I delete? I think every equation is necessary.What should I do?

Thank you for your reading and answering!

Best regards,

Wu

#2

From what you are saying, you are actually missing an equation that determines the last variable!

#3

I’m sorry for my poor English,and which variable am I missing? Thank you.

#4

You will never get an answer here. You are the model builder and the only one knowing how you derived the equations you entered into Dynare. This is not a Dynare problem. If you cannot tell from your model which equation is too much, nobody else can.

#5

Thanks very much!! I have solved the problem. But here comes another one.

Error using print_info (line 52)
One of the eigenvalues is close to 0/0 (the absolute value of numerator and denominator is smaller than 1e-6)

Error in check (line 76)
print_info(info, options.noprint);

Error in test2 (line 397)
oo_.dr.eigval = check(M_,options_,oo_);

Error in dynare (line 120)
evalin(‘base’,fname) ;

This problem is made by the parameters or something else?
test2.mod (3.35 KB)

#6

Use model_diagnostics(M_,options_,oo_) to see that you added a redundant equation and that you did not solve the issue.

#7

Amazing!It’s useful to me. The model has colinear equations.
Thanks a lot.