[olg] Editorial Suggestions

[HumphreyYang]

Comments by @longye-tian.

Code

• Combine the two graphs showing equilibrium. (Delete the first plot and leave the one with the equilibrium point. #499
• x = 1000 -> n = 1000
• Vectorize

k_grid_next = np.empty_like(k_grid)

for i in range(x):
    k_grid_next[i] = k_update(k_grid[i], α, β)

• Add y label for plot in 24.6.3
• Remove these duplicated lines

R_vals = np.linspace(0.3, 1)
model = create_olg_model()

Content

• Add a comparison to the Solow-Swan growth model.
• 'Long run growth' -> 'Long-run growth'.
• Explain the Euler equation and give economic intuition.
• firm problem -> firm's problem.
• factor price $\times$ factor (
  \max_{k_t, \ell_t} \{ k^{\alpha}_t \ell_t^{1-\alpha} - R_t k_t - \ell_t w_t \}
  to
  \max_{k_t, \ell_t} \{ k^{\alpha}_t \ell_t^{1-\alpha} - R_t k_t - w_t \ell_t \}.
• Add assumption for labor market clearing condition to get $\ell = 1$.
• 'interest rate' -> 'gross interest rate'.
• Recalibrate the model to get an interest rate > 0.
• '45 degree' -> '45-degree'.
• Add an explanation on CRRA (add a sentence: as $\gamma \to 1$ this becomes a log utility).
• Lecture on Ponzi scheme and OLG? @longye-tian for more details.

[longye-tian]

This issue is now closed by pull request #438 #503.