Hello all,

I have an open econ model whose private equilibrium solution based on simple rules for policy instruments works fine.

Now, I want to solve the cooperative Ramsey model. For that I am commenting the rules and adding:

```
//Coop:
planner_objective nc*(Cc^(1-sigmma)/(1-sigmma) - Hc^(1+pssi)/(1+pssi)) + na*(Ca^(1-sigmma)/(1-sigmma) - Ha^(1+pssi)/(1+pssi)) + nb*(Cb^(1-sigmma)/(1-sigmma) - Hb^(1+pssi)/(1+pssi)) ;
```

`ramsey_model(instruments=(tauc, taua, taub), planner_discount=betta);`

However, the model cannot be solved. Particularly the Steady State.

How can I fix it?

I am attaching the files (I am using an external SS file)

These are the errors for my static eqs:

Residuals of the static equations and associated error prompt:

```
Equation number 1 : 9.9506e-06
Equation number 2 : 4.155e-05
Equation number 3 : -1.9845e-05
Equation number 4 : -1.6481e-05
Equation number 5 : 6.6635e-06
Equation number 6 : -2.9347e-05
Equation number 7 : 0
Equation number 8 : -1.7612e-06
Equation number 9 : 2.1726e-07
Equation number 10 : -1.0377e-07
Equation number 11 : 1.8547e-06
Equation number 12 : -6.5419e-05
Equation number 13 : 6.1709e-05
Equation number 14 : -5.4146e-05
Equation number 15 : 8.9604e-05
Equation number 16 : -0.00014363
Equation number 17 : 0
Equation number 18 : 0
Equation number 19 : 0
Equation number 20 : 0
Equation number 21 : 0
Equation number 22 : 0
Equation number 23 : -0.00058798
Equation number 24 : 0.0021149
Equation number 25 : -0.0023462
Equation number 26 : -2.0432e-05
Equation number 27 : 7.3494e-05
Equation number 28 : -8.153e-05
Equation number 29 : 0
Equation number 30 : 0
Equation number 31 : 0
Equation number 32 : -1.4996e-06
Equation number 33 : -1.1858e-06
Equation number 34 : -1.2173e-06
Equation number 35 : -8.3757e-05
Equation number 36 : 0.00033047
Equation number 37 : -0.00034977
Equation number 38 : 0.0017844
Equation number 39 : -0.0019964
Equation number 40 : -0.00071619
Equation number 41 : -1.5148e-06
Equation number 42 : -1.5148e-06
Equation number 43 : 0
Equation number 44 : -2.1081e-07
Equation number 45 : 1.0069e-07
Equation number 46 : -6.8953e-06
Equation number 47 : 2.7317e-05
Equation number 48 : -3.676e-05
Equation number 49 : 1.7135e-06
Equation number 50 : 1.884e-06
Equation number 51 : 1.0773e-06
Equation number 52 : 4.6537e-05
Equation number 53 : -2.3037e-05
Equation number 54 : 7.749e-05
Error using print_info (line 32)
Ramsey: The solution to the static first order conditions for optimal policy could not be found.
Either the model doesn't have a steady state, there are an infinity of steady states, or the guess
values are too far from the solution
Error in steady (line 102)
print_info(info,options_.noprint, options_);
Error in MaPCoord_Lv.driver (line 1195)
steady;
Error in dynare (line 293)
evalin('base',[fname '.driver']) ;
```

Also, just to check, I solved the model with habits of consumption and I get a different error this time but my eqs resids look different:

```
Residuals of the static equations:
Equation number 1 : 0.20887
Equation number 2 : 0.1149
Equation number 3 : 0.1149
Equation number 4 : -0.47804
Equation number 5 : -0.25472
Equation number 6 : -0.25472
Equation number 7 : 0
Equation number 8 : 0
Equation number 9 : 0
Equation number 10 : 0
Equation number 11 : 0
Equation number 12 : 0
Equation number 13 : 0
Equation number 14 : 0
Equation number 15 : 0
Equation number 16 : 0
Equation number 17 : 0
Equation number 18 : 0
Equation number 19 : 0
Equation number 20 : 0
Equation number 21 : 0
Equation number 22 : 0
Equation number 23 : 0
Equation number 24 : 0
Equation number 25 : 0
Equation number 26 : 0
Equation number 27 : 0
Equation number 28 : 0
Equation number 29 : 0
Equation number 30 : 0
Equation number 31 : 0
Equation number 32 : 0
Equation number 33 : 0
Equation number 34 : 0
Equation number 35 : 0
Equation number 36 : 0
Equation number 37 : 0
Equation number 38 : 0
Equation number 39 : 0
Equation number 40 : 0
Equation number 41 : 0
Equation number 42 : 0
Equation number 43 : 0
Equation number 44 : 0
Equation number 45 : 0
Equation number 46 : 0
Equation number 47 : 0
Equation number 48 : 0
Equation number 49 : 0
Equation number 50 : 0
Equation number 51 : 0
Equation number 52 : 0
Equation number 53 : 0
Equation number 54 : 0
Error using print_info (line 32)
Ramsey: The steady state file computation for the Ramsey problem resulted in NaNs at the initial
values of the instruments
Error in steady (line 102)
print_info(info,options_.noprint, options_);
Error in MaPCoord_Lv.driver (line 1381)
steady;
Error in dynare (line 293)
evalin('base',[fname '.driver']) ;
>>
```

Thanks for your help!.

Camilo

find_ss.m (1.8 KB) MaPCoord_Lv_steadystate.m (5.9 KB) MaPCoord_Lv.mod (17.9 KB) MaPCoord_sseqs.m (7.4 KB)