Training a model on a dataset refers to the process of using a machine learning algorithm to learn the patterns, relationships, and representations within the data.
The model learns from the input data and its corresponding output labels to make predictions or decisions on new, unseen data.
Here’s a step-by-step explanation of the training process:
1. Input Data: The dataset consists of input samples and their corresponding output labels. In supervised learning, the model is provided with pairs of input data and the correct output labels.
2. Initialization: The model is initialized with random parameters or weights. These parameters define the initial state of the model and will be adjusted during training.
3. Forward Pass: The input data is fed into the model, and the model performs a forward pass. This involves processing the input through the neural network (or other algorithm) to generate predictions.
4. Loss Calculation: The model’s predictions are compared to the actual output labels using a loss function. The loss function quantifies how well or poorly the model is performing on the training data.
5. Backward Pass (Backpropagation): The model adjusts its parameters (weights) to minimize the loss. This is done through a process called backpropagation, where the gradients of the loss with respect to the model’s parameters are calculated.
6. Optimization: An optimization algorithm (e.g., gradient descent) is used to update the model’s parameters in the direction that minimizes the loss. This process is repeated iteratively for multiple epochs (passes through the entire dataset).
7. Model Evaluation: Periodically, the model’s performance is evaluated on a separate validation dataset to check for overfitting and to ensure generalization to unseen data.
8. Termination: The training process continues for a predefined number of epochs or until a certain criterion is met, such as convergence of the loss.
9. Inference: Once training is complete, the trained model can be used for making predictions on new, unseen data.