Loss surface
A loss surface is a function that assigns a loss value to each possible setting of a model’s parameters.
Math and Architectures of Deep Learning
The geometric representation of a loss function over parameter space, where height indicates loss value for each parameter setting.
- How it is used
- Frames loss minimization as navigation across parameter space during supervised training.
- How deep it goes
- Defines the surface, maps it to geometry, and links it to gradients and minimization, but stops short of algorithmic variants beyond basic descent.
- Examples
- Uses concentric circles, concentric spheres, coaxial cylinders, heat maps, and a canyon or ravine analogy.
- What you can do after
- Apply gradient descent and momentum to move toward lower loss on a neural network surface.
Read how Math and Architectures of Deep Learning explains loss surface →
Sutskever's List
A loss landscape is the function relating a model's parameter values to its loss across parameter space.
- How it is used
- Frames the apparent difficulty of training deep networks and explains how AlexNet-era optimization challenged that view.
- How deep it goes
- Explains terrain metaphors, valley curvature, high-dimensional behavior, and mini-batch smoothing without formal analysis.
- Examples
- Uses a long, narrow valley to contrast oscillating large steps with slow progress along the valley’s base.
- What you can do after
- Understand why high-dimensional loss surfaces and mini-batch gradient averaging complicate the expectation that optimization gets trapped in poor minima.
Related concepts
- gradient descentused by · Gradient descent is an iterative optimization method that updates parameters opposite the gradient of an objective function to reduce its value.
- momentumused by · Momentum is an optimization technique that incorporates a running history of gradients or parameter updates to smooth and accelerate movement during training.
- parameteruses · A model parameter is a numerical value, such as a weight or bias, that is learned or set to determine how a model computes outputs.
- hypersurfaceequivalent to · A surface of arbitrary dimension used here as the geometric shape of a loss surface in high-dimensional space.
- mean squared errorequivalent to · Mean squared error is the arithmetic mean of the squared differences between corresponding predicted and target numerical values.
- objective functionequivalent to · An objective function assigns values to candidate solutions, predictions, or parameter settings according to a criterion to be minimized or maximized.
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