NKPC coding in Dynare


I’m currently working on a model with the NKPC device, but I get a bit confused with they way of coding it. I use this functional form,

but regarding inflation equation, should i used this one,

or this one,

Results are strongly different, I don’t get why.

Results are different, because Dynare treats everything with a (+1) as being conditional expectations. Hence, the first equation holds at every point in time, while the second one holds in expectations.

actually is

Thanks for you answer jpfeifer.

In your opinion, should I use the first or second one equation ? I get better results with the second one.

Use the one that is consistent with your model.