Multiclass PAC learning with bandit feedback is characterized by the new bandit DS dimension via pseudo-boxes, yielding sharp sample complexity scaling with total neighbors.
Online set learning with randomized precision or recall feedback is learnable exactly when the hypothesis class has finite VC dimension, though standard empirical risk minimization can fail and algorithms must handle feedback dependencies to achieve regret bounds.
Strategic classification can make VC dimension 1 problems unlearnable, but geometric definability via first-order formulas over real exponentiation preserves learnability with controlled sample complexity.