Part 1 – Top Scikit Learn Tips for Building Efficient Machine Learning Workflows


This series of articles draws inspiration and key concepts from Data School’s valuable “TOP 50 Scikit-learn Tips and Tricks” resource. While not a direct adaptation, each article aims to build upon those core ideas, providing comprehensive explanations, code examples, and practical considerations for effective implementation. The goal is to empower you with a deeper understanding and the ability to confidently apply these scikit-learn techniques in your machine learning projects.


1. Fit-Transform on Train Data, Transform on Test Data: Prevent information leakage from test data into the model by fitting transformers on the training data and only applying the learned transformations to the test data.

from sklearn.preprocessing import StandardScaler

scaler = StandardScaler()
X_train_scaled = scaler.fit_transform(X_train)
X_test_scaled = scaler.transform(X_test)  # Don't fit again!

2. OneHotEncoder over pandas.get_dummies: Use OneHotEncoder for seamless integration with scikit-learn pipelines and better handling of new categories in unseen data.

from sklearn.preprocessing import OneHotEncoder

encoder = OneHotEncoder(handle_unknown='ignore')
X_train_encoded = encoder.fit_transform(X_train[['categorical_column']])
X_test_encoded = encoder.transform(X_test[['categorical_column']])

3. OrdinalEncoder for Ordinal Features: Use OrdinalEncoder for features with inherent order (e.g., “low,” “medium,” “high”). Avoid LabelEncoder for features, as it assigns arbitrary numeric values without preserving order.

from sklearn.preprocessing import OrdinalEncoder

encoder = OrdinalEncoder(categories=[['low', 'medium', 'high']])
X_train_encoded = encoder.fit_transform(X_train[['ordinal_feature']])
X_test_encoded = encoder.transform(X_test[['ordinal_feature']])

4. Pipelines for Streamlined Workflows: Chain preprocessing and modeling steps using Pipelines for reproducibility and efficiency.

from sklearn.pipeline import Pipeline
from sklearn.linear_model import LogisticRegression

pipeline = Pipeline([
    ('scaler', StandardScaler()),
    ('encoder', OneHotEncoder()),
    ('classifier', LogisticRegression())
])
pipeline.fit(X_train, y_train)
predictions = pipeline.predict(X_test)

That’s it! I hope these insights from Data School’s “TOP 50 Scikit-learn Tips and Tricks” have been useful for your machine learning journey. Stay tuned for Part 2, where we’ll delve deeper into even more practical techniques and considerations to boost your scikit-learn expertise! See you then!tunesharemore_vertadd_photo_alternate