# Help with exercise

**URL:** https://forum.dynare.org/t/help-with-exercise/4852
**Category:** Dynare help (legacy posts)
**Created:** [20 July 2015 13:11 UTC](https://forum.dynare.org/t/help-with-exercise/4852 "2015-07-20T13:11:54Z")
**Posts on this page:** 2
**Page:** 1

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### Author: ![Mikele91lp](https://forum.dynare.org/letter_avatar_proxy/v4/letter/m/ebca7d/32.png) [@Mikele91lp](https://forum.dynare.org/u/Mikele91lp)
#### Post date: [20 July 2015 13:11 UTC](https://forum.dynare.org/t/help-with-exercise/4852/1 "2015-07-20T13:11:54Z")

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Hello everyone! I should transfer in " dynare " th model containing in the file “model\_project.pdf” and perform the exercise contained in the last page of the other pdf .  
I attach the mod file . Can someone please help me?  
[progetto11.mod](https://forum.dynare.org/uploads/default/original/2X/d/db6670dbe993aac0d42a2ede1c69eabac34c35fe.mod) (1.06 KB)  
[exercise.pdf](https://forum.dynare.org/uploads/default/original/2X/5/51173100c9a41bce256ecb83862aab3a55d3364e.pdf) (88.7 KB)  
[model\_project.pdf](https://forum.dynare.org/uploads/default/original/2X/5/58ac53f9cc115b21e958afa51af7d4ceb786fa6e.pdf) (94.3 KB)

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### Author: ![jpfeifer](https://forum.dynare.org/user_avatar/forum.dynare.org/jpfeifer/32/5044_2.png) [@jpfeifer](https://forum.dynare.org/u/jpfeifer)
#### Post date: [21 July 2015 08:22 UTC](https://forum.dynare.org/t/help-with-exercise/4852/2 "2015-07-21T08:22:21Z")

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Check your model. If you define pip as a parameter, your equation

`lambda=lambda(+1)+R-pip(+1);
`  
is not linear anymore. Moreover, using a leaded parameter makes no sense.  
Use

`resid(1);` before steady to see the problematic equations.