Data preprocessing is a critical step in the machine learning pipeline. Here's a structured guide to mastering advanced methods:

🔍 Key Concepts

  • Data Cleaning:
    Remove outliers 🚫 and handle missing values 📉.

    Missing Data
    Example: Use interpolation for time-series data or remove rows with nulls.
  • Feature Engineering:
    Create meaningful features 🛠️ like polynomial features or interaction terms.

    Feature Selection
    Tip: Apply domain knowledge to derive new variables (e.g., `Age_Group` from numerical age).
  • Data Normalization:
    Scale features to a standard range (e.g., 0-1) using Min-Max or Z-Score normalization.

    Data Normalization
    Note: Always normalize *after* feature selection to avoid bias.

📚 Further Reading

🧠 Practical Tools

  • Pandas: df.fillna(), df.interpolate()
  • Scikit-learn: StandardScaler, RobustScaler
  • NumPy: Array operations for data transformation

By mastering these techniques, you'll unlock better model accuracy! 🚀