Combinatorics

Meteorology

Descent (aeronautics)

Mathematics

Evolutionary biology

Biology

Algorithm

Data mining

Variety (cybernetics)

Gradient descent

Function (biology)

Artificial intelligence

Geography

Stochastic gradient descent

Measure (data warehouse)

Computer science

Conjecture

Artificial neural network

Journal of Statistical Mechanics Theory and Experiment

We show that a variety of modern deep learning tasks exhibit a ‘double-descent’ phenomenon where, as we increase model size, performance first gets worse and then gets better. Moreover, we show that double descent occurs not just as a function of model size, but also as a function of the number of training epochs. We unify the above phenomena by defining a new complexity measure we call the effective model complexity and conjecture a generalized double descent with respect to this measure. Furthermore, our notion of model complexity allows us to identify certain regimes where increasing (even quadrupling) the number of train samples actually hurts test performance.

Deep double descent: where bigger models and more data hurt*