# Error in deterministic simulation

**URL:** https://forum.dynare.org/t/error-in-deterministic-simulation/4711
**Category:** Dynare help (legacy posts)
**Created:** [23 May 2015 10:31 UTC](https://forum.dynare.org/t/error-in-deterministic-simulation/4711 "2015-05-23T10:31:18Z")
**Posts on this page:** 2
**Page:** 1

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### Author: ![St\_aueb](https://forum.dynare.org/letter_avatar_proxy/v4/letter/s/ecc23a/32.png) [@St\_aueb](https://forum.dynare.org/u/St_aueb)
#### Post date: [23 May 2015 10:31 UTC](https://forum.dynare.org/t/error-in-deterministic-simulation/4711/1 "2015-05-23T10:31:18Z")

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Hi all  
I’m working on a simple 3 period OLG model where I study some tax/spending reforms. I was trying a deterministic shock (exogenous decrease in a tax rate) to check the transitional dynamics of my model. But when I ran the mod file this message appears:

Error using simul (line 60)  
SIMUL: error in model specification : variable km doesn’t appear as current  
variable.

Error in OLG\_log (line 449)  
simul();

Error in dynare (line 180)  
evalin(‘base’,fname) ;

What “doesn’t appear as current variable” means?I post the mod file.Any ideas??

Thank you!  
[OLG\_log.mod](https://forum.dynare.org/uploads/default/original/2X/3/3faeb54dbb1ab15e9c35a2b82f06b57ed78ec338.mod) (7.78 KB)

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### Author: ![St\_aueb](https://forum.dynare.org/letter_avatar_proxy/v4/letter/s/ecc23a/32.png) [@St\_aueb](https://forum.dynare.org/u/St_aueb)
#### Post date: [23 May 2015 11:04 UTC](https://forum.dynare.org/t/error-in-deterministic-simulation/4711/2 "2015-05-23T11:04:48Z")

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No worries  
It was a variable timing problem. Solved it.