# Can Dynare simulate the impact of multiple shocks on a single variable?

**URL:** https://forum.dynare.org/t/can-dynare-simulate-the-impact-of-multiple-shocks-on-a-single-variable/27558
**Category:** Stochastic simulations
**Created:** [10 May 2025 10:59 UTC](https://forum.dynare.org/t/can-dynare-simulate-the-impact-of-multiple-shocks-on-a-single-variable/27558 "2025-05-10T10:59:15Z")
**Posts on this page:** 2
**Page:** 1

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### Author: ![alliance\_xz](https://forum.dynare.org/letter_avatar_proxy/v4/letter/a/c0e974/32.png) [@alliance\_xz](https://forum.dynare.org/u/alliance_xz)
#### Post date: [10 May 2025 10:59 UTC](https://forum.dynare.org/t/can-dynare-simulate-the-impact-of-multiple-shocks-on-a-single-variable/27558/1 "2025-05-10T10:59:15Z")

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Can Dynare simulate the effect of multiple shocks on a single variable?  
For example, when shock A and shock B simultaneously affect Y, what is the change in Y?  
If I include `var shockA; var shockB;` in the `shocks` block, they still seem to be treated as independent shocks.

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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: [10 May 2025 11:04 UTC](https://forum.dynare.org/t/can-dynare-simulate-the-impact-of-multiple-shocks-on-a-single-variable/27558/2 "2025-05-10T11:04:42Z")

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See

> [@Sequences of both negative and positive shockss](https://forum.dynare.org/t/sequences-of-both-negative-and-positive-shockss/5449/4):
>
> Using the simult\_-function of Dynare, you can simulate the model with any given sequence of shocks that you want. An example is at [github.com/JohannesPfeifer/DSGE\_mod/blob/master/RBC\_news\_shock\_model/RBC\_news\_shock\_model.mod](https://github.com/JohannesPfeifer/DSGE_mod/blob/master/RBC_news_shock_model/RBC_news_shock_model.mod)

and

> [@Simultaneous shocks](https://forum.dynare.org/t/simultaneous-shocks/1659/2):
>
> Hi, this is possible in Dynare by specifying a correlated shock. E.g. call the common epscommon and add it to both equations you want to perturb. Note that this is not usually done in the literature as most papers consider first-order approximated model. There everything is linear. Hence, there is not additional value of simultaneously shocking two variables as the IRF is simply the sum of the two individual IRFs.