Raw data is often in formats that models or analysis tools cannot use directly.
Transformation = converting data into a usable form.
🔄 Common Transformations:
1. Type Conversion
"25"→25(string to integer)
2. Date Formatting
- Convert
"12/01/2024"→ standard format likeYYYY-MM-DD
3. Scaling Values
Important for machine learning models.
Why?
Different scales can bias models.
Example:
- Age: 20–60
- Salary: 20,000–1,00,000
Salary dominates unless scaled.
📏 Common Scaling Methods:
- Normalization (0 to 1 range)
- Standardization (mean = 0, std = 1)
💡 Key Idea:
Transformation ensures:
- Consistency
- Compatibility
- Better model performance