README.md

metadata

title: Zürich Apartment Price Predictor
emoji: 🏠
colorFrom: blue
colorTo: red
sdk: gradio
sdk_version: 6.8.0
app_file: app.py
pinned: false
short_description: Machine Learning Apartment Rent Price Predictor for Zurich

Model Iterations Documentation

Task: Apartment Price Prediction (Regression)

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Summary of Iterative Process

Iteration	Objective	Key Changes	Models Used	CV Mean R²	CV Std Dev	Test MAE (CHF)	Fit Diagnosis
1	Build baseline model	- Basic cleaning - 7 numerical features - Train-test split (80/20) - 5-fold CV	Linear Regression Random Forest (n_estimators=100)	0.429 (LR) 0.441 (RF)	0.073 (LR) 0.075 (RF)	549.90 (LR) 553.98 (RF)	☐ Overfitting ☑ Underfitting ☐ Good Fit
2	Improve through feature engineering	- 7 new features created - Feature scaling (Ridge) - Hyperparameter tuning - 5-fold CV	Ridge (alpha=10.0) Random Forest (n_estimators=200, max_depth=15) Gradient Boosting (n_estimators=150, max_depth=5)	0.461 (Ridge) 0.481 (RF) 0.521 (GB)	0.073 (Ridge) 0.070 (RF) 0.068 (GB)	541.11 (Ridge) 544.92 (RF) 537.78 (GB)	☐ Overfitting ☐ Underfitting ☑ Good Fit

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Notes

Metric: MAE (Mean Absolute Error), R² (5-Fold Cross-Validation)

Created Features:

• rooms_per_sqm: Raumdichte (Zimmer pro m²)
• wealth_index: Wohlstandsindikator (tax_income × emp normalisiert)
• is_zurich_city: Binär-Feature für Zürich Stadt (PLZ 8000-8099)
• pop_emp_ratio: Bevölkerungs-Arbeitsplatz-Verhältnis
• log_area: Log-Transformation der Wohnfläche
• log_pop: Log-Transformation der Bevölkerung
• log_tax_income: Log-Transformation des Steuereinkommens

Final Selected Features:

• area (28.7% importance)
• log_area (25.0% importance)
• is_zurich_city (13.0% importance)
• rooms_per_sqm (12.2% importance)
• rooms, log_pop, pop_dens, pop, pop_emp_ratio, log_tax_income, emp, wealth_index, tax_income, frg_pct

Final Model: Gradient Boosting Regressor

Reason for Selection: Best R² score (0.521) and lowest MAE (537.78 CHF). Consistent performance between CV and test set with lowest standard deviation (±67.62 CHF), indicating stable predictions.