Adjusting the regularization strength
Your current Lasso model has an \(R^2\) score of 84.7%. When a model applies overly powerful regularization it can suffer from high bias, hurting its predictive power.
Let's improve the balance between predictive power and model simplicity by tweaking the alpha parameter.
Bu egzersiz, kursun bir parçasıdır
Dimensionality Reduction in Python
Egzersiz talimatları
- Find the highest value for
alphathat gives an \(R^2\) value above 98% from the options:1,0.5,0.1, and0.01.
Uygulamalı etkileşimli egzersiz
Bu egzersizi bu örnek kodu tamamlayarak deneyin.
# Find the highest alpha value with R-squared above 98%
la = Lasso(____, random_state=0)
# Fits the model and calculates performance stats
la.fit(X_train_std, y_train)
r_squared = la.score(X_test_std, y_test)
n_ignored_features = sum(la.coef_ == 0)
# Print peformance stats
print(f"The model can predict {r_squared:.1%} of the variance in the test set.")
print(f"{n_ignored_features} out of {len(la.coef_)} features were ignored.")