Loss as a Landscape to Descend
Picture error as hills and valleys.
What Loss Measures
Your model's loss is a single number that says how wrong its predictions are. Smaller loss means better predictions. Training is just the quest to shrink it. 📉
Loss Depends on Weights
The same data gives different loss depending on your weights. Change a weight and the loss moves up or down. So loss is really a function of the weights.
loss = compute_loss(weights, data)