MLG 028 Hyperparameters 2

Notes and resources:  ocdevel.com/mlg/28  Try a walking desk to stay healthy while you study or work! More hyperparameters for optimizing neural networks. A focus on regularization, optimizers, feature scaling, and hyperparameter search methods. Hyperparameter Search Techniques Grid Search involves testing all possible permutations of hyperparameters, but is computationally exhaustive and suited for simpler, less time-consuming models. Random Search selects random combinations of hyperparameters, potentially saving time while potentially missing the optimal solution. Bayesian Optimization employs machine learning to continuously update and hone in on efficient hyperparameter combinations, avoiding the exhaustive or random nature of grid and random searches. Regularization in Neural Networks L1 and L2 Regularization penalize certain parameter configurations to prevent model overfitting; often smoothing overfitted parameters. Dropout randomly deactivates neurons during training to ensure the model doesn't over-rely on specific neurons, fostering better generalization. Optimizers Optimizers like Adam, which combines elements of momentum and adaptive learning rates, are explained as vital tools for refining the learning process of neural networks. Adam, being the most sophisticated and commonly used optimizer, improves upon simpler techniques like momentum by incorporating more advanced adaptative features. Initializers The importance of weight initialization is underscored with methods like uniform random initialization and the more advanced Xavier initialization to prevent neural networks from starting in 'stuck' states. Feature Scaling Different scaling methods such as standardization and normalization are used to scale feature inputs to small, standardized ranges. Batch Normalization is highlighted, integrating scaling directly into the network to prevent issues like exploding and vanishing gradients through the normalization of layer outputs. Links Bayesian Optimization Optimizers (SGD): Momentum -> Adagrad -> RMSProp -> Adam -> Nadam