# Defined: Deep Studying in Tensorflow — Chapter zero

1. Enter Characteristic Vector (X): It’s the traits of the enter dataset which helps in drawing a conclusion a couple of sure habits. It might be one hot-encoded, embeddings, and many others.
2. Weights and Biases (W & B): Typically, weights, w1,w2,… are actual numbers expressing the significance of the respective inputs to the output. Biases are an additional threshold worth added to the output.
3. Loss (L): Loss is the target operate that tells how shut the prediction is with respect to the unique end result. It’s also referred to as price operate. The target as a coaching mechanism is all the time to attenuate the worth of this price operate. In different phrases, we need to discover a set of weights and biases which make the associated fee as small as doable. There are a number of loss features as Imply Squared Error (MSE) widespread amongst regression issues, categorical or binary cross-entropy widespread amongst classification issues.
4. Optimizers: These are used to attenuate the loss operate by updating the weights and biases. Stochastic Gradient Descent is a well-liked one. Right here is a pleasant rationalization for optimizers.
5. Activation Operate: Activation operate decides, whether or not a neuron needs to be activated or not by calculating a weighted sum and additional including bias with it. However, why do we want activation operate? The reply is: if we chain a number of linear transformations, all we get is a linear transformation. For instance, if f(x) = 2x+Three and g(x) = 5x-1 in two neuron from adjoining layer. Then, chaining these two will give linear operate i.e. f(g(x)) = 2(5x-1)+Three. So, if we don’t have non-linearity between layers, then even a deep stack of layers is equal to a single layer. The aim of the activation operate is to introduce non-linearity into the output of a neuron. ReLU (Rectified-Linear Unit) is probably the most broadly used activation operate.
6. Studying Price(η): It’s the charge at which the weights and biases needs to be modified in every replace.