🌱 Week 7 Homework — Feedback

Student: Ignazio Nunzi
Assignment: Solow Model with Technological & Population Growth

⚠️ Overall Assessment

Result: ⚠️ Partial (<50% Correct)

You explored several comparative-static scenarios and produced multiple figures, but the core Week 7 deliverable is incomplete. The main script calls simulate_growth_tech yet no helper function file is included, so the homework section cannot run. In addition, the calibration diverges from the required horizon (T=80, k0=3.1201) and the final plot omits the steady-state benchmarks that were explicitly requested. Addressing these items will bring the submission in line with expectations.

🔍 Task-by-Task Checklist

# Requirement Status Notes
1 Separate simulate_growth_tech.m helper with correct signature ❌ Missing file ⇒ script errors when run.
2 Helper preallocates arrays and final values ❌ Dependent on missing helper.
3 Law of motion divides by (1+n)(1+g) ❌ Cannot verify without helper implementation.
4 Technology path updates with (1+g) ❌ Same issue as above.
5 Main script sets required parameters (α, δ, s, T=80, k0, A0) ⚠️ Uses T=50, k0=0.5 instead of instructed calibration.
6 Scenario matrix includes (0,0), (0.01,0.02), (0.02,0.03) ✅ Stored in param_sets.
7 Reuses simulation outputs for later steps ⚠️ Results saved in a struct, but only after missing helper call.
8 Plot k_t for the three scenarios ⚠️ fig4 mixes k_t (solid) and y/A (dashed) on the same axes; clearer to use separate plots.
9 Add steady-state reference lines on k_t plot ❌ No yline overlays for k*.
10 Plot y_t/A_t for the three scenarios ⚠️ Plotted as dashed lines on same axes; missing dedicated figure.
11 Add steady-state reference lines on y_t/A_t plot ❌ Missing (y/A)* lines.
12 Save figures to Figures/ (PNG/PDF) ✅ fig_convergence_k_yeff_growth.png created.
13 Provide steady-state summary (table or print) ❌ No numeric output of k* / (y/A)*.
14 Interpretation answers both homework questions ⚠️ Narrative comments present, but not tied to measured results and truncated mid-sentence.
15 Code hygiene (comments, no cd, folder guard) ✅ Uses mkdir guard, extensive commentary.

Score: 4/15 tasks fully correct, 4/15 partial, 7/15 missing → ⚠️

📈 Evidence & Highlights

```133:170:docs/week7/Homework submissions/Ignazio Nunzi/IgnazioH7.m for i = 1:size(param_sets,1) n = param_sets(i,1); g = param_sets(i,2);

[k, y, c, A] = simulate_growth_tech(alpha, s, delta, n, g, k0, A0, T);
...
plot(results(i).k, 'LineWidth', 1.6, 'Color', colors(i,:));
y_eff = results(i).y ./ results(i).A;
plot(y_eff, '--', 'LineWidth', 1.6, 'Color', colors(i,:)); ```

Without the helper file, this block raises “Undefined function or variable ‘simulate_growth_tech’”.

💡 Suggestions for Improvement

  1. Include simulate_growth_tech.m in the submission folder. Follow the starter structure so the law of motion divides by (1+n)(1+g) and returns k, y, c, A per scenario.
  2. Adopt the requested calibration: set T=80 and k0=3.1201 in the homework section to match the instructions and reference solution.
  3. Produce two dedicated figures—one for k_t and one for y_t/A_t—each with horizontal yline benchmarks for the respective steady states.
  4. Print a steady-state table using fprintf so your written interpretation can cite the numeric targets and convergence speeds.
  5. Tighten the interpretation: explicitly answer how higher n/g change steady-state levels (per effective worker) and whether convergence speeds up or slows down, referencing the output from step 4.

🧾 Summary

I like the exploratory mindset and the extra comparative-static figures, but the essential deliverables are currently incomplete. Add the helper function, align the calibration, and incorporate the steady-state diagnostics to reach a passing submission.

Grade: ⚠️ (Partial <50% correct)