# Zero Lower Bounds in Gertler/Karadi 2011

**URL:** https://forum.dynare.org/t/zero-lower-bounds-in-gertler-karadi-2011/6031
**Category:** Dynare help (legacy posts)
**Created:** [12 February 2017 15:03 UTC](https://forum.dynare.org/t/zero-lower-bounds-in-gertler-karadi-2011/6031 "2017-02-12T15:03:57Z")
**Posts on this page:** 2
**Page:** 1

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### Author: ![New\_to\_Dynare](https://forum.dynare.org/letter_avatar_proxy/v4/letter/n/ea666f/32.png) [@New\_to\_Dynare](https://forum.dynare.org/u/New_to_Dynare)
#### Post date: [12 February 2017 15:03 UTC](https://forum.dynare.org/t/zero-lower-bounds-in-gertler-karadi-2011/6031/1 "2017-02-12T15:03:57Z")

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Hi all,

I am trying to introduce at Zero Lower Bounds constraint in the original Gertler & Karadi (2011) code. I am pretty new to Dynare, but does anyone have an idea of how to do this?

I have attached the original code.

Thanks in advance,

Frank  
[FA.mod](https://forum.dynare.org/uploads/default/original/2X/a/a5df1dc47cb99b290e01449e793ddd4a415c843e.mod) (7.45 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: [13 February 2017 13:23 UTC](https://forum.dynare.org/t/zero-lower-bounds-in-gertler-karadi-2011/6031/2 "2017-02-13T13:23:48Z")

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This is a stochastic model. Introducing the ZLB in rigorous way is (almost) impossible with Dynare. You would i) have to either go for the experimental “stochastic extended path”, ii) do perfect foresight and use Guerrieri/Iacoviello’s “Occbin”, or iii) use a sequence of monetary policy shock to get the ZLB exactly binding in an ad-hoc way.