源码、讲义1.3如何计算稳态值

1、1.3如何计算稳态值 OutlineGeneral steps to find steady statesSome special casesA simple exampleGeneral steps to find steady states1. all parameters need to be calibrated or estimated before s.s. can be calculated.2. remove all exogenous shocks from model;3. remove all time subscripts from variables;4. remov

2、e the expectation operator from model;Some parametersThe discount factor beta = 1/(1+r) where r is real rate, if at quarterly frequency, r=1%, and 4% annually. So at quarterly frequency beta=0.99 and if at yearly frequency, beta=0.96; The capital share alpha in production function is usually calibra

3、ted to 0.3 0.4 in the literature. 0.36 is typically calibrated.The depreciation rate delta: is usually calibrated to 0.025=2.5% based on quarterly frequency which means that 10% annually. Some Special CasesThe steady state values of shocks, the AR(1) variables, is usually set to unity; Log(A_t) = rh

4、o*log(A_t-1) + eps_tIn some model, the steady state value of labor is set to 1/3 which means that households spends about 8 hours in one day to work.In most cases, we assume the steady states of inflation which is less likely to be calculated from model. An ExampleA simple RBC model is easily calcul

5、ated since variable number is small. (See pdf file)But sometimes, even for a simple model, it will take advantage of some numerical programs to solve s.s.A more complex model will pose some challenges. We will focus on this point later on chapter 4 where medium DSGE model is focused. SummaryI. You should be able to calculate the s.s. of small and simple model by following the general steps list above.II. All parameters should be calibrated or estimated before you can calculated the stead