🌱 Week 7 Homework — Feedback

Student: Simone Iudice
Assignment: Solow Model with Technological & Population Growth

✅ Overall Assessment

Result: ✅ More than 50% Correct

Good submission with correct helper function and proper parameter calibration. The code runs cleanly and produces clear subplot figures saved to the correct directory. The main gaps are: (1) missing steady-state reference lines on both plots, (2) no printed steady-state summary, and (3) interpretation is present but could be more explicit about convergence speed. The economic discussion addresses steady-state effects well but doesn’t clearly answer the convergence speed question.

🔍 Task-by-Task Checklist

# Requirement Status Notes
1 Separate simulate_growth_tech.m helper with correct signature ✅ Provided with four outputs.
2 Helper preallocates arrays and final values ✅ Column vectors, final period handled.
3 Law of motion divides by (1+n)(1+g) ✅ Correct implementation.
4 Technology path updates with (1+g) ✅ Included in loop.
5 Main script sets required parameters (α, δ, s, T=80, k0, A0) ✅ Matches homework specification.
6 Scenario matrix includes (0,0), (0.01,0.02), (0.02,0.03) ✅ Stored in n_values and g_values arrays.
7 Reuses simulation outputs for later steps ⚠️ Re-runs function for plotting.
8 Plot k_t for the three scenarios ✅ Top subplot shows all paths.
9 Add steady-state reference lines on k_t plot ❌ Missing yline overlays.
10 Plot y_t/A_t for the three scenarios ✅ Bottom subplot implemented.
11 Add steady-state reference lines on y_t/A_t plot ❌ Missing yline overlays.
12 Save figures to Figures/ (PNG/PDF) ✅ Saved to Figures/ as PNG (note typo in filename: “Transion”).
13 Provide steady-state summary (table or print) ❌ No numerical output of k*/(y/A)*.
14 Interpretation answers both homework questions ⚠️ Addresses steady-state effects well but convergence speed discussion is incomplete.
15 Code hygiene (comments, no cd, folder guard) ✅ Clean structure, no absolute paths.

Score: 9/15 tasks fully correct, 1/15 partial, 5/15 missing → ✅

📈 Evidence & Highlights

56:69:docs/week7/Homework submissions/week7homework_SimoneIudice/week7_homework.m % Plot transition path of k_t subplot(2,1,1); plot(1:T, k, 'LineWidth', 1.5); hold on ... % Plot transition path of y_t / A_t subplot(2,1,2); plot(1:T, y_effective, 'LineWidth', 1.5); hold on

💡 Suggestions for Improvement

  1. Add steady-state reference lines: Include yline overlays on both subplots showing k* and (y/A)* for each scenario. Calculate these using k_star = (s / (delta + n + g + n*g))^(1/(1-alpha)) and y_star = k_star^alpha.
  2. Print steady-state summary: Add a fprintf block that reports k* and (y/A)* for each scenario. This will provide quantitative backing for your interpretation.
  3. Expand convergence speed discussion: Your interpretation mentions that higher n and g “increase the rate of convergence” but doesn’t explain why. Please elaborate on the mechanism (higher effective depreciation creates a stronger restoring force).

🧾 Summary

Solid implementation with correct economics. Adding steady-state overlays, a quantitative summary, and expanding the convergence speed discussion will complete the submission.

Grade: ✅ (More than 50% correct)