Regressione lineare vs albero di regressione

In questo esercizio confronterai l’RMSE sul set di test di dt con quello ottenuto da un modello di regressione lineare. Abbiamo già istanziato un modello di regressione lineare lr e lo abbiamo addestrato sullo stesso insieme di dati di dt.

La matrice delle caratteristiche X_test, l’array delle etichette y_test, il modello di regressione lineare addestrato lr, la funzione mean_squared_error importata con l’alias MSE e rmse_dt dall’esercizio precedente sono disponibili nel tuo workspace.

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Machine Learning con modelli ad alberi in Python

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Istruzioni dell'esercizio

Predici le etichette del set di test usando il modello di regressione lineare (lr) e assegna il risultato a y_pred_lr.
Calcola l’MSE sul set di test e assegna il risultato a mse_lr.
Calcola l’RMSE sul set di test e assegna il risultato a rmse_lr.

Esercizio pratico interattivo

Prova a risolvere questo esercizio completando il codice di esempio.

# Predict test set labels 
____ = ____.____(____)

# Compute mse_lr
____ = ____(____, ____)

# Compute rmse_lr
____ = ____

# Print rmse_lr
print('Linear Regression test set RMSE: {:.2f}'.format(rmse_lr))

# Print rmse_dt
print('Regression Tree test set RMSE: {:.2f}'.format(rmse_dt))

Modifica ed esegui il codice

Questo esercizio fa parte del corso

Machine Learning con modelli ad alberi in Python

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Classification and Regression Trees (CART) are a set of supervised learning models used for problems involving classification and regression. In this chapter, you'll be introduced to the CART algorithm.

Exercise 1: Albero decisionale per la classificazione Exercise 2: Allena il tuo primo albero di classificazione Exercise 3: Valuta l'albero di classificazione Exercise 4: Regressione logistica vs albero di classificazione Exercise 5: Apprendimento dell'albero di classificazione Exercise 6: Far crescere un albero di classificazione Exercise 7: Usare l'entropia come criterio Exercise 8: Entropia vs indice di Gini Exercise 9: Albero decisionale per la regressione Exercise 10: Allena il tuo primo albero di regressione Exercise 11: Valuta l’albero di regressione Exercise 12: Regressione lineare vs albero di regressione

Esercizio in corso

The bias-variance tradeoff is one of the fundamental concepts in supervised machine learning. In this chapter, you'll understand how to diagnose the problems of overfitting and underfitting. You'll also be introduced to the concept of ensembling where the predictions of several models are aggregated to produce predictions that are more robust.

Exercise 1: Generalization Error Exercise 2: Complexity, bias and variance Exercise 3: Overfitting and underfitting Exercise 4: Diagnose bias and variance problems Exercise 5: Instantiate the model Exercise 6: Evaluate the 10-fold CV error Exercise 7: Evaluate the training error Exercise 8: High bias or high variance?Exercise 9: Ensemble Learning Exercise 10: Define the ensemble Exercise 11: Evaluate individual classifiers Exercise 12: Better performance with a Voting Classifier

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Exercise 1: Bagging Exercise 2: Define the bagging classifier Exercise 3: Evaluate Bagging performance Exercise 4: Out of Bag Evaluation Exercise 5: Prepare the ground Exercise 6: OOB Score vs Test Set Score Exercise 7: Random Forests (RF)Exercise 8: Train an RF regressor Exercise 9: Evaluate the RF regressor Exercise 10: Visualizing features importances

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Exercise 1: Adaboost Exercise 2: Define the AdaBoost classifier Exercise 3: Train the AdaBoost classifier Exercise 4: Evaluate the AdaBoost classifier Exercise 5: Gradient Boosting (GB)Exercise 6: Define the GB regressor Exercise 7: Train the GB regressor Exercise 8: Evaluate the GB regressor Exercise 9: Stochastic Gradient Boosting (SGB)Exercise 10: Regression with SGB Exercise 11: Train the SGB regressor Exercise 12: Evaluate the SGB regressor

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Exercise 1: Tuning a CART's Hyperparameters Exercise 2: Tree hyperparameters Exercise 3: Set the tree's hyperparameter grid Exercise 4: Search for the optimal tree Exercise 5: Evaluate the optimal tree Exercise 6: Tuning a RF's Hyperparameters Exercise 7: Random forests hyperparameters Exercise 8: Set the hyperparameter grid of RF Exercise 9: Search for the optimal forest Exercise 10: Evaluate the optimal forest Exercise 11: Congratulations!