# The Jacobian of the static model is singular even though i can change the parameter to run mod file **URL:** \ **Category:** Stochastic simulations\ **Created:** [21 December 2025 04:42 UTC](https://forum.dynare.org/t/the-jacobian-of-the-static-model-is-singular-even-though-i-can-change-the-parameter-to-run-mod-file/28138 "2025-12-21T04:42:26Z")\ **Posts on this page:** 5\ **Page:** 1
**Author:** ![JackChou](https://forum.dynare.org/letter_avatar_proxy/v4/letter/j/e47774/32.png) [@JackChou](https://forum.dynare.org/u/JackChou)\ **Post date:** [21 December 2025 04:42 UTC](https://forum.dynare.org/t/the-jacobian-of-the-static-model-is-singular-even-though-i-can-change-the-parameter-to-run-mod-file/28138/1 "2025-12-21T04:42:26Z")
It is ok to run the mod file if i set phiy = 0.2, but when i run the model\_diagnostics(M\_,options\_,oo\_) or i set phiy = 0.5 [monetary.mod](https://forum.dynare.org/uploads/short-url/o8AixzJYSbffyn2O9FfCpRmT7lK.mod) (7.7 KB) , it shows MODEL\_DIAGNOSTICS: The Jacobian of the static model is singular MODEL\_DIAGNOSTICS: there is 1 collinear relationships between the variables and the equations Collinear variables: y i k c w R lambda n pi mc dp z1 z2 pis m mu Collinear equations 18 ---
**Author:** ![JackChou](https://forum.dynare.org/letter_avatar_proxy/v4/letter/j/e47774/32.png) [@JackChou](https://forum.dynare.org/u/JackChou)\ **Post date:** [21 December 2025 07:33 UTC](https://forum.dynare.org/t/the-jacobian-of-the-static-model-is-singular-even-though-i-can-change-the-parameter-to-run-mod-file/28138/2 "2025-12-21T07:33:38Z")
I do not know if the problem lies in Taylor Rule part? The error message is that if i remove the sticky price part about these variables. Run model\_diagnostics(M\_,options\_,oo\_), it turns out ![image](https://forum.dynare.org/uploads/default/original/3X/e/f/ef6ced80c259b9e37a45aabd5cf7c31b4650dacb.png) ---
**Author:** ![JackChou](https://forum.dynare.org/letter_avatar_proxy/v4/letter/j/e47774/32.png) [@JackChou](https://forum.dynare.org/u/JackChou)\ **Post date:** [21 December 2025 12:24 UTC](https://forum.dynare.org/t/the-jacobian-of-the-static-model-is-singular-even-though-i-can-change-the-parameter-to-run-mod-file/28138/3 "2025-12-21T12:24:51Z")
[monetary.mod](https://forum.dynare.org/uploads/short-url/18YBRX692KZ6LEPtleWgZ63Kgp8.mod) (4.1 KB) The code is updated. If i use ln(R/Rs) = rho\_R\*ln(R(-1)/Rs)+ (1-rho\_R)\*phiy\*ln(y/steady\_state(y))+(1-rho\_R)\*phipi\*ln(pi/pi0)+ eR; it occurs the above error. If i use ln(R/Rs) = rho\_R\*ln(R(-1)/Rs)+ (1-rho\_R)\*phiy\*ln(y/y(-1))+(1-rho\_R)\*phipi\*ln(pi/pi0)+ eR;, it occurs no error? Why?? ---
**Author:** ![JackChou](https://forum.dynare.org/letter_avatar_proxy/v4/letter/j/e47774/32.png) [@JackChou](https://forum.dynare.org/u/JackChou)\ **Post date:** [21 December 2025 12:45 UTC](https://forum.dynare.org/t/the-jacobian-of-the-static-model-is-singular-even-though-i-can-change-the-parameter-to-run-mod-file/28138/4 "2025-12-21T12:45:15Z")
Can we use it in the Taylor rule? Sometimes it runs out “Exogenous variables are not allowed in the context of the STEADY\_STATE() operator.” ---
**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:** [22 December 2025 09:45 UTC](https://forum.dynare.org/t/the-jacobian-of-the-static-model-is-singular-even-though-i-can-change-the-parameter-to-run-mod-file/28138/5 "2025-12-22T09:45:57Z")
See > [@An infinity of steady states with Taylor rules](https://forum.dynare.org/t/an-infinity-of-steady-states-with-taylor-rules/4026/4): > > Could it be that you are trying to use the steady state operator to compute something that cannot be set endogenously? Take inflation: every percentage point higher steady state inflation will increase the steady state nominal interest accordingly. But any consistent combination of both (via the link the Fisher equation provides) is feasible. You need to pin down one of them by setting the value. The model cannot do this for you.