- Linear neuron
- Binary threshold neuron
- Stochastic binary neuron
- Sigmoid neuron
- Tanh function
- Rectified linear unit (ReLU)
In an artificial intelligence interview, when asked about different activation functions or neurons used in neural networks, you could provide a comprehensive list including:
- Sigmoid Function (Logistic): This function squashes the input values between 0 and 1, suitable for binary classification tasks.
- Hyperbolic Tangent (Tanh) Function: Similar to the sigmoid function but squashes the input values between -1 and 1, often used in hidden layers of neural networks.
- Rectified Linear Unit (ReLU): This activation function returns 0 for negative inputs and the input value for positive inputs, effectively introducing non-linearity in the network.
- Leaky ReLU: A variant of ReLU that allows a small, positive gradient for negative inputs, helping to mitigate the “dying ReLU” problem.
- Parametric ReLU (PReLU): An extension of Leaky ReLU where the slope of the negative part is learned during training.
- Exponential Linear Unit (ELU): Similar to ReLU but with a smooth curve for negative inputs, which can help speed up convergence and improve robustness.
- Scaled Exponential Linear Unit (SELU): A self-normalizing activation function that maintains a constant mean and variance of the inputs, often used in deep learning architectures.
- Softmax Function: Typically used in the output layer of a neural network for multi-class classification tasks, it converts raw scores into probabilities.
- Linear Activation: A simple identity function where the output is proportional to the input, often used in the output layer for regression tasks.
- Swish Function: Proposed as a self-gated activation function, it performs as a smoother alternative to ReLU.
- Gaussian Error Linear Units (GELUs): Introduces a non-monotonicity into the network, which can help in certain contexts.
- Maxout Units: Neurons that take the maximum activation from a set of linear functions of the input.
- Hard Tanh: A piecewise linear function that approximates the hyperbolic tangent function, with faster computations.
- Softplus: A smooth approximation of ReLU, with non-zero gradients for all inputs.
- Binary Step: Simple thresholding function where values above a certain threshold are set to 1 and values below to 0, mainly used in binary classification problems.
When discussing these activation functions, it’s important to consider their properties, advantages, and limitations in different contexts and tasks.