gzx0321 / heterogeneous_firms

Heterogeneous firms

heterogeneous_firms

Heterogeneous firms (monopolistic, endogeneous exit, Bertrand competition, RBC/NK).

Structure of the code

Naming conventions

• "run_...py": this file runs linear solutions of the models
• "dynamamics_...py": these files contain all dynamic equations needed for the models except equations for households and firms
• "steady_state...py": these files solve for the steady states and contain households problems for HA models
• "het_firm.py": this file contains heterogeneous firms problems

Available models

• Heterogeneous firms with monopolistic competition, with endogeneous exit, with Bertrand competition. All models are available as RBC and as NK versions.

Figures

All codes for figures could be found in "figures.py".

Addional changes to the source code to the source code

The solution method and codes are taken from Auclert, Bardóczy, Rognlie, Straub (2021): "Using the Sequence-Space Jacobian to Solve and Estimate Heterogeneous-Agent Models" and their github folder https://github.com/shade-econ/sequence-jacobian Additionally, I have modified the steady state calculation by adding "ss_with_dist_iter" function. This function guesses the distribution, solves heterogeneous agent block and then update the distribution guess. This is repeated until convergence. This function is needed for the Bertrand competition as firms need guesses for the distribution to come up with their policy functions.

Comments

To choose between different heterogeneous firms' problems change function name (from firm to firm_exit, for example) in three places: two times in the "steady_state...py" file where heterogeneous firms' problem is solved and one time in "dynamics...py" file in "pricing_het" block definition.