def learn_decision_tree(stratified_data_csv_file, save_filepath):
# read the stratified dataset
data = np.genfromtxt(stratified_data_csv_file, delimiter = ',', skip_header = 1)
X, y = data[:, :-1], data[:, -1]
# do a 70-30 train-test split.
X_train, X_test, y_train, y_test = train_test_split(X, y, test_size = 0.30, random_state = 10)
# testing parameters
params = {
'max_depth': [None, 5, 10, 20, 30],
'min_samples_split': [2, 5, 10]
}
stratified_k_fold = StratifiedKFold(n_splits = 10)
classifier = GridSearchCV(DecisionTreeClassifier(), params, cv = stratified_k_fold, verbose = 5)
classifier.fit(X_train, y_train)
best_classifier = classifier.best_estimator_
y_pred = best_classifier.predict(X_test)
# model statistics
print('Decision Trees Model Statistics')
print('Best params: {0}'.format(classifier.best_params_))
model_stats.compute_basic_stats(y_test, y_pred)
model_stats.compute_roc_score(y_test, y_pred)
model_stats.plot_normalized_confusion_matrix(
y_test, y_pred, 'Decision Trees Classifier Normalized Confusion Matrix'
)
# fit the classifier on the complete dataset once we get best parameters
best_classifier = DecisionTreeClassifier(**classifier.best_params_)
best_classifier.fit(X, y)
# save the model
save_model(best_classifier, save_filepath)
def learn_sgd(stratified_data_csv_file, save_filepath):
# read the stratified dataset
data = np.genfromtxt(stratified_data_csv_file,
delimiter=',',
skip_header=1)
X, y = data[:, :-1], data[:, -1]
# do a 70-30 train-test split.
X_train, X_test, y_train, y_test = train_test_split(X,
y,
test_size=0.30,
random_state=10)
# standardize train and test data (scale X_train to [0, 1] range)
scaler = StandardScaler().fit(X_train)
X_train = scaler.fit_transform(X_train)
X_test = scaler.fit_transform(X_test)
# testing parameters
params = {
'loss':
['hinge', 'log', 'modified_huber', 'squared_hinge', 'perceptron'],
'penalty': ['l1', 'l2', 'elasticnet'],
'alpha': [1e-5, 1e-4, 1e-3],
'max_iter': [200]
}
stratified_k_fold = StratifiedKFold(n_splits=10)
classifier = GridSearchCV(SGDClassifier(),
params,
cv=stratified_k_fold,
verbose=5)
classifier.fit(X_train, y_train)
best_classifier = classifier.best_estimator_
y_pred = best_classifier.predict(X_test)
# model statistics
print('SGD Model Statistics')
print('Best params: {}'.format(classifier.best_params_))
model_stats.compute_basic_stats(y_test, y_pred)
model_stats.compute_roc_score(y_test, y_pred)
model_stats.plot_normalized_confusion_matrix(
y_test, y_pred, 'SGD Classifier Normalized Confusion Matrix')
# fit the classifier on the complete dataset once we get best parameters
best_classifier = SGDClassifier(**classifier.best_params_)
best_classifier.fit(X, y)
# save the model
save_model(best_classifier, save_filepath)
def learn_bagging(stratified_data_csv_file, save_filepath):
# read the stratified dataset
data = np.genfromtxt(stratified_data_csv_file,
delimiter=',',
skip_header=1)
X, y = data[:, :-1], data[:, -1]
# do a 70-30 train-test split.
X_train, X_test, y_train, y_test = train_test_split(X,
y,
test_size=0.30,
random_state=10)
############
# testing parameters
params = {
'base_estimator': [None, KNeighborsClassifier()],
'n_estimators': [10, 20, 30],
'max_samples': [0.50, 0.75],
'max_features': [0.50, 0.75]
}
stratified_k_fold = StratifiedKFold(n_splits=10)
classifier = GridSearchCV(BaggingClassifier(),
params,
cv=stratified_k_fold,
verbose=5,
n_jobs=3)
classifier.fit(X_train, y_train)
best_classifier = classifier.best_estimator_
y_pred = best_classifier.predict(X_test)
print('Bagging Classifier Statistics')
print('Best params: {}'.format(classifier.best_params_))
model_stats.compute_basic_stats(y_test, y_pred)
model_stats.compute_roc_score(y_test, y_pred)
model_stats.plot_normalized_confusion_matrix(
y_test, y_pred, 'Bagging Classifier Normalized Confusion Matrix')
# fit the classifier on the complete dataset once we get best parameters
best_classifier = BaggingClassifier(**classifier.best_params_)
best_classifier.fit(X, y)
# save the model
save_model(best_classifier, save_filepath)
def learn_rbf_svm(stratified_data_csv_file, save_filepath):
# read the stratified dataset
data = np.genfromtxt(stratified_data_csv_file,
delimiter=',',
skip_header=1)
X, y = data[:, :-1], data[:, -1]
# do a 70-30 train-test split.
X_train, X_test, y_train, y_test = train_test_split(X,
y,
test_size=0.30,
random_state=10)
# standardize train and test data (scale X_train to [0, 1] range)
scaler = StandardScaler().fit(X_train)
X_train = scaler.fit_transform(X_train)
X_test = scaler.fit_transform(X_test)
# testing parameters
params = {
'kernel': ['rbf'],
'C': np.logspace(-2, 2, 5),
'gamma': np.logspace(-2, 2, 5)
}
stratified_k_fold = StratifiedKFold(n_splits=10)
classifier = GridSearchCV(SVC(), params, cv=stratified_k_fold, verbose=5)
classifier.fit(X_train, y_train)
best_classifier = classifier.best_estimator_
y_pred = best_classifier.predict(X_test)
# model statistics
print('RBF Kernel SVM Model Statistics')
print('Best params: {}'.format(classifier.best_params_))
model_stats.compute_basic_stats(y_test, y_pred)
model_stats.compute_roc_score(y_test, y_pred)
model_stats.plot_normalized_confusion_matrix(
y_test, y_pred,
'RBF Kernel SVM Classifier Normalized Confusion Matrix')
# fit the classifier on the complete dataset once we get best parameters
best_classifier = SVC(**classifier.best_params_)
best_classifier.fit(X, y)
# save the model
save_model(best_classifier, save_filepath)
def learn_voting_classifier(stratified_data_csv_file, save_filepath):
# read the stratified dataset
data = np.genfromtxt(stratified_data_csv_file,
delimiter=',',
skip_header=1)
X, y = data[:, :-1], data[:, -1]
# do a 70-30 train-test split.
X_train, X_test, y_train, y_test = train_test_split(X,
y,
test_size=0.30,
random_state=10)
# classifier to test
classifiers = [
# ('dt', DecisionTreeClassifier(max_depth = None, min_samples_split = 2)),
('knn', KNeighborsClassifier(n_neighbors=5)),
# ('lin_svm', SVC(C = 100.0, kernel = 'linear')),
# ('logreg', LogisticRegression(C = '100.0', max_iter = '200', penalty = 'l1')),
('nb', GaussianNB()),
# ('rbf_svm', SVC(C = 100.0, gamma = 0.1, kernel = 'rbf')),
('rf',
RandomForestClassifier(max_depth=20,
min_samples_split=5,
n_estimators=30)),
('sgd',
SGDClassifier(alpha=0.0001, loss='log', max_iter=200, penalty='l2')),
('bagging',
BaggingClassifier(base_estimator=None,
max_features=0.75,
max_samples=0.5,
n_estimators=30)),
# ('boosting', GradientBoostingClassifier(
# learning_rate = 0.1, max_depth = 5, min_samples_split = 5, n_estimators = 300
# ))
]
# create all possible combinations
combinations_ = list()
for i in range(len(classifiers)):
combinations_.extend(list(itertools.combinations(classifiers, i + 1)))
# testing parameters
params = {
'estimators': combinations_,
'voting': [
'soft',
'hard',
],
}
stratified_k_fold = StratifiedKFold(n_splits=10)
classifier = RandomizedSearchCV(VotingClassifier(estimators=None),
params,
cv=stratified_k_fold,
verbose=5,
n_jobs=3)
classifier.fit(X_train, y_train)
best_classifier = classifier.best_estimator_
y_pred = best_classifier.predict(X_test)
# model statistics
print('Voting Classifier Statistics')
print('Best params: {}'.format(classifier.best_params_))
model_stats.compute_basic_stats(y_test, y_pred)
model_stats.compute_roc_score(y_test, y_pred)
model_stats.plot_normalized_confusion_matrix(
y_test, y_pred, 'Voting Classifier Normalized Confusion Matrix')
# fit the classifier on the complete dataset once we get best parameters
best_classifier = VotingClassifier(**classifier.best_params_)
best_classifier.fit(X, y)
# save the model
save_model(best_classifier, save_filepath)
def learn(training_data_infile,
trained_model_outfile=None,
display_metrics: bool = False,
gs_verbose: int = 0,
n_jobs=1):
"""
Trains a voting classifier
:param training_data_infile: Csv file containing training data (labeled)
• The last column should be training labels
• Csv file can contain header (line 1 is skipped)
• Use: machine_learning.aux.data_processing.create_training_dataset
:param trained_model_outfile: where to save the model
:param display_metrics: whether to print model metrics or not
:param gs_verbose: verbosity of GridSearch
:param n_jobs: GridSearch parallel jobs
:return:
"""
training_data_infile = os.path.abspath(training_data_infile)
# start
print('-' * 25)
print('Starting learning for `Voting Classifier`')
print('training_infile: {:s}'.format(
str(os.path.relpath(training_data_infile))))
print('trained_outfile: {:s}'.format(
str(os.path.relpath(trained_model_outfile)
) if trained_model_outfile is not None else 'None'))
print('display_metric: {:s}, gs_verbose: {:d}, n_jobs: {:d}'.format(
str(display_metrics), gs_verbose, n_jobs))
print()
# read the stratified dataset
data = np.genfromtxt(training_data_infile, delimiter=',', skip_header=1)
features_x, target_y = data[:, :-1], data[:, -1]
# do a 70-30 train-test split.
x_train, x_test, y_train, y_test = train_test_split(features_x,
target_y,
test_size=0.30)
scaler = StandardScaler()
features_x = scaler.fit_transform(features_x)
x_train = scaler.fit_transform(x_train)
x_test = scaler.fit_transform(x_test)
# classifier to test
classifiers = [
# ('dt', DecisionTreeClassifier(max_depth = None, min_samples_split = 2)),
('knn', KNeighborsClassifier(n_neighbors=5)),
# ('lin_svm', SVC(C = 100.0, kernel = 'linear')),
# ('logreg', LogisticRegression(C = '100.0', max_iter = '200', penalty = 'l1')),
('nb', GaussianNB()),
# ('rbf_svm', SVC(C = 100.0, gamma = 0.1, kernel = 'rbf')),
('rf',
RandomForestClassifier(max_depth=20,
min_samples_split=5,
n_estimators=30)),
('sgd',
SGDClassifier(alpha=0.0001, loss='log', max_iter=200, penalty='l2')),
('bagging',
BaggingClassifier(base_estimator=None,
max_features=0.75,
max_samples=0.5,
n_estimators=30)),
# ('boosting', GradientBoostingClassifier(
# learning_rate = 0.1, max_depth = 5, min_samples_split = 5, n_estimators = 300
# ))
]
# create all possible combinations
combinations_ = list()
for i in range(len(classifiers)):
combinations_.extend(list(itertools.combinations(classifiers, i + 1)))
# testing parameters
params = {
'estimators': combinations_,
'voting': [
'soft',
'hard',
],
}
stratified_k_fold = StratifiedKFold(n_splits=10)
classifier = RandomizedSearchCV(VotingClassifier(estimators=None),
params,
cv=stratified_k_fold,
scoring={
'accuracy':
make_scorer(accuracy_score),
'precision':
make_scorer(precision_score),
'recall': make_scorer(recall_score),
'roc_auc': make_scorer(roc_auc_score),
'f1': make_scorer(f1_score),
},
refit='f1',
verbose=gs_verbose,
n_jobs=n_jobs)
classifier.fit(x_train, y_train)
best_classifier = classifier.best_estimator_
y_pred = best_classifier.predict(x_test)
print('Voting Classifier Statistics')
print('Best params: {}'.format(classifier.best_params_))
model_stats.compute_basic_stats(y_test, y_pred)
model_stats.compute_roc_score(y_test, y_pred)
model_stats.plot_normalized_confusion_matrix(
y_test, y_pred, 'Voting Classifier Normalized Confusion Matrix')
# fit the classifier on the complete dataset once we get best parameters
complete_classifier = VotingClassifier(**classifier.best_params_)
complete_classifier.fit(features_x, target_y)
# save the model
if trained_model_outfile:
try:
trained_model_outfile = os.path.abspath(trained_model_outfile)
save_model(complete_classifier, trained_model_outfile)
print('Classifier successfully saved at: {:s}'.format(
str(os.path.relpath(trained_model_outfile))))
except Exception as exc:
print('Error while saving model! Could not save at: '
'{:s}'.format(str(os.path.relpath(trained_model_outfile))))
print(exc)
print('-' * 25)
return complete_classifier