Lakukan tuning hyperparameter secara manual

Jika Anda sudah mengetahui nilai hyperparameter yang ingin ditetapkan, Anda juga dapat mendefinisikan secara manual hyperparameter sebagai sebuah grid. Buka modelLookup("gbm") atau cari gbm di daftar model yang tersedia di caret dan periksa bagian Tuning Parameters.

Catatan: Sama seperti sebelumnya, bc_train_data serta pustaka caret dan tictoc telah dimuat sebelumnya.

Latihan ini adalah bagian dari kursus

Penyetelan Hyperparameter di R

Petunjuk latihan

Definisikan grid hyperparameter berikut untuk Gradient Boosting Model: jumlah pohon 200; kompleksitas pohon 1; laju pembelajaran 0,1; dan jumlah minimum contoh himpunan latih pada sebuah node untuk mulai melakukan pemisahan 10.
Terapkan grid tersebut pada fungsi train() dari caret.

Latihan interaktif praktis

Cobalah latihan ini dengan menyelesaikan kode contoh berikut.

# Define hyperparameter grid.
hyperparams <- expand.grid(___ = 200, 
                           ___ = 1, 
                           ___ = 0.1, 
                           ___ = 10)

# Apply hyperparameter grid to train().
set.seed(42)
gbm_model <- train(diagnosis ~ ., 
                   data = bc_train_data, 
                   method = "gbm", 
                   trControl = trainControl(method = "repeatedcv", number = 5, repeats = 3),
                   verbose = FALSE,
                   ___ = hyperparams)

Edit dan Jalankan Kode

Latihan ini adalah bagian dari kursus

Penyetelan Hyperparameter di R

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4.8+

Mulai Kursus Gratis

Why do we use the strange word "hyperparameter"? What makes it hyper? Here, you will understand what model parameters are, and why they are different from hyperparameters in machine learning. You will then see why we would want to tune them and how the default setting of caret automatically includes hyperparameter tuning.

Exercise 1: Parameter vs hyperparameter Exercise 2: Parameter model vs. hyperparameter Exercise 3: Hyperparameter dalam model linear Exercise 4: Apa saja koefisiennya?Exercise 5: Ulasan dasar-dasar Machine Learning Exercise 6: Machine learning dengan caret Exercise 7: Skema resampling Exercise 8: Penyetelan hyperparameter di caret Exercise 9: Hyperparameter dalam Stochastic Gradient Boosting Exercise 10: Mengubah jumlah hiperparameter yang akan dituning Exercise 11: Lakukan tuning hyperparameter secara manual

Latihan Saat Ini

In this chapter, you will learn how to tune hyperparameters with a Cartesian grid. Then, you will implement faster and more efficient approaches. You will use Random Search and adaptive resampling to tune the parameter grid, in a way that concentrates on values in the neighborhood of the optimal settings.

Exercise 1: Hyperparameter tuning in caret Exercise 2: Finding hyperparameters Exercise 3: Cartesian grid search in caret Exercise 4: Plot hyperparameter model output Exercise 5: Grid vs. Random Search Exercise 6: Grid search with range of hyperparameters Exercise 7: Find train() option for random search Exercise 8: Random search with caret Exercise 9: Adaptive resampling Exercise 10: Advantages of Adaptive Resampling Exercise 11: Adaptive Resampling with caret

Here, you will use another package for machine learning that has very convenient hyperparameter tuning functions. You will define a Cartesian grid or perform Random Search, as well as advanced techniques. You will also learn different ways to plot and evaluate models with different hyperparameters.

Exercise 1: Machine learning with mlr Exercise 2: Machine Learning with mlr Exercise 3: Modeling with mlr Exercise 4: Grid and random search with mlr Exercise 5: Random search with mlr Exercise 6: Perform hyperparameter tuning with mlr Exercise 7: Evaluating hyperparameters with mlr Exercise 8: Why to evaluate tuning?Exercise 9: Evaluating hyperparameter tuning results Exercise 10: Advanced tuning with mlr Exercise 11: Define advanced tuning controls Exercise 12: Define aggregated measures Exercise 13: Setting hyperparameters

In this final chapter, you will use h2o, another package for machine learning with very convenient hyperparameter tuning functions. You will use it to train different models and define a Cartesian grid. Then, You will implement a Random Search use stopping criteria. Finally, you will learn AutoML, an h2o interface which allows for very fast and convenient model and hyperparameter tuning with just one function.

Exercise 1: Machine learning with h2o Exercise 2: Prepare data for modelling with h2o Exercise 3: Modeling with h2o Exercise 4: Grid and random search with h2o Exercise 5: Grid search with h2o Exercise 6: Random search with h2o Exercise 7: Stopping criteria Exercise 8: Automatic machine learning with H2O Exercise 9: AutoML in h2o Exercise 10: Scoring the leaderboard Exercise 11: Extract h2o models and evaluate performance Exercise 12: Wrap-up