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Activation Functions

31 problems

  • Attention step 2 — scale by √dₖ, then softmaxMedium
  • ReLU forward + backwardEasy
  • Sigmoid forward + backwardEasy
  • The classifier head — FC + softmaxMedium
  • Feature map — bias and ReLUEasy
  • Binary output head — probability and decisionEasy
  • Dense layer — sigmoid forward passEasy
  • Why nonlinearity — collapsing two linear layersMedium
  • Neuron — one unit, three activationsEasy
  • Output layer — predict the classEasy
  • ReLU — find the dead neuronsEasy
  • Dense layer with ReLU (the production hidden default)Easy
  • Sigmoid derivative from the activationEasy
  • Softmax with temperatureEasy
  • Vanishing gradients through sigmoid layersEasy
  • Dynamic-Tanh (DyT)Medium
  • GELU backward (tanh approximation)Medium
  • GELU forward (tanh approximation)Easy
  • √dₖ and softmax saturation (row entropy)Medium
  • Why mask before softmax, not afterMedium
  • He weight initializationEasy
  • Leaky ReLU activationEasy
  • Log-softmaxEasy
  • Logistic regression — probability from a scoreEasy
  • Logistic regression — the sigmoid reflection identityEasy
  • Noisy top-k gatingMedium
  • SELU activationEasy
  • Softmax backwardMedium
  • Softmax (multinomial) regressionMedium
  • SwiGLU activationMedium
  • Swish / SiLU activationEasy