I am reading Monetary policy, inflation, and the business cycle: an introduction to the new Keynesian framework and its applications by Gali.
In this question I am going to use the output $Y_t$ as an example. I am going to use the notation from Gali.
- $y$ is notation for the steady state.
- $y_t^n$ is notation for the the natural level of output.
- $\tilde{y}_t = y_t-y_t^n$ is the output gap: deviation from the natural level.
- $\hat{y}_t = y_t-y$ is the deviation from steady state.
My question is: Intuitively speaking, what is the difference between steady state level and natural level?
Note: $y_t = \log Y_t$