08. Feature Selection Methods for Trading Models
PRDTM2-785 AI Trading C2 L3 Vid5 Feature Selection Methods For Trading Models
Note: At time 5:57, In the last plot, the label should read High variance (overfit), not High variance (underfit).
The curve is too flexible and matches noise in the training data, which is the hallmark of overfitting, not underfitting.
Understanding Feature Selection for Model Optimization
Feature selection is crucial in machine learning, focusing on identifying essential variables to enhance model performance. Here's a concise guide:
The Significance of Feature Selection:
- Reduces the risk of overfitting by minimizing irrelevant data.
- Enhances model accuracy and efficiency.
Techniques for Feature Selection:
- Correlation Matrix & Heat Map:
- Calculates correlations between features to find redundant ones.
- Visual representation in heat maps helps pinpoint relationships.
- Recursive Feature Elimination (RFE):
- Forward RFE: Starts with no features, adding them one by one, evaluating performance.
- Backward RFE: Begins with all features, removing them iteratively while assessing impact.
- Principal Component Analysis (PCA):
- Transforms data to a simpler form, retaining most variance with fewer features.
- Metric-based Assessment:
- Models like Random Forest assign importance scores to features.
- Regularization:
- Methods like L1/L2 shrink coefficients, reduce model complexity, and select key features effectively.
By implementing these methods, models become both robust and scalable, leading to better decision-making in various applications.
SOLUTION:
- A correlation matrix can help identify highly correlated features.
- Regularization techniques can help prevent overfitting and perform feature selection.
- Principal Component Analysis (PCA) reduces dimensionality by creating new uncorrelated features.