Hi, all.

As you all know, Bayesian DSGE estimation using dynare starts with finding posterior mode.

However, I have continuously watching the following error message.

[code]Error using chol

Matrix must be positive definite.

Error in metropolis_hastings_initialization (line 68)

d = chol(vv);

Error in random_walk_metropolis_hastings (line 69)

ix2, ilogpo2, ModelName, MhDirectoryName, fblck, fline, npar, nblck, nruns, NewFile, MAX_nruns,

d ] = …

Error in dynare_estimation_1 (line 931)

feval(options_.posterior_sampling_method,objective_function,options_.proposal_distribution,xparam1,invhess,bounds,dataset_,options_,M_,estim_params_,bayestopt_,oo_);

Error in dynare_estimation (line 70)

dynare_estimation_1(var_list,dname);

Error in kor_4_1st (line 186)

dynare_estimation(var_list_);

Error in dynare (line 120)

evalin(‘base’,fname) ;

[/code]

As far as I know, above error can be solved by imposing different initial starting values.

However, It is quite time-consuming and I failed to start estimation eventually.

According to dynare user guide, we can impose mode file by adding “mode_file” command.

I manually coded matlab file to search posterior modes and then apply them into dynare.

Finally, estimation is successfully done.

However, I wanted to check computed posterior mode is correctly computed. (because it is calculated my own matlab code)

So, I did two things with a program that can estimate successfully without different starting values from prior mean.

- estimation using dynare without mode_file
- estimation using dynare with mode__file

I expected exactly same log data density. But they are slightly different from each other.

I know they can be slightly different but I want to ask how you think about this situation.