Introduction to the Neural Network Model, Glossary, and Backpropagation

This article was published as a part of the Data Science Blogathon.

Introduction

If you’re a software developer who’s interested in learning how neural networks function, you’ve come to the perfect spot. We will assist novices to understand what neural networks are, what a neural network model is, and how to expand their knowledge to other areas of the subject in this tutorial.

What is a Neural Network?

Before we get into computational jargon, it’s important to grasp the role of neural networks in our daily lives.

The term “neural” derives from the term “neuron,” which refers to a single nerve cell. That’s correct — a neural network is simply a collection of neurons that carry out routine tasks in our daily lives.

Pattern recognition, object identification, and intelligence all play a significant role in solving the difficulties we confront on a daily basis. While these reflexes are executed with such easily that we are unaware of them, the reality is that they are tough to automate.

Example:

• Children memorize the appearance of an apple

• An animal that recognizes its mother or owner

• Perceiving the temperature of an object

These complex computations are carried out by our neural networks.

Humans have now developed a computing system capable of performing in a way akin to that of our nervous system. These are referred to as artificial neural networks (ANNs).

While we first employed ANNs to handle simple tasks, the rise in computing power has enabled us to develop a rather robust neural network architecture capable of solving more complex issues.

In the following part, we’ll go through ANN in further detail.

What is an Artificial Neural Network Model?

An artificial neural network, or ANN, is a multi-layer, fully connected neural network that consists of an input layer, hidden layers, and an output layer.

An ANN is seen in the picture below.

If you look closely, you’ll discover that each node in a layer is connected to every node in the layer above and below it.

The network grows deeper as the number of hidden levels increases.

Consider the appearance of an individual node in the output or concealed layer.

As you can see, the node receives a large number of inputs. It adds all the weights together and outputs the sum through a non-linear activation function.

This node’s output becomes the node’s input in the subsequent layer.

It’s critical to keep in mind that the signal will always shift from left to right. The final result will be provided once all nodes have followed the protocol.

This is how a node’s equation appears

In the above equation, b denotes bias. It serves as the input to all nodes and is always set to 1.

Bias enables the activation function outcome to be shifted to the left or right.

Read more about Artificial Neural Networks here.

Artificial Neural Network Model Glossary

Let’s take a look at some of the fundamental words you should be familiar with when it comes to an artificial neural network model.

Inputs

The data that is initially given into the neural network from a source is referred to as the input. Its purpose is to provide data to the network in order for it to make a judgment or prediction about the information it receives. In most cases, the neural network model receives real-valued inputs that should be supplied to a neuron in the input layer.

Training Set

Training sets are inputs for which you already know the proper outputs. These are utilized to assist the neural network with training and memory for the given input set.

Outputs

Depending on the input it receives, each neural network generates a prediction or a judgment. A set of integers or a Boolean judgment can be used to represent this output. A single neuron in the output layer is responsible for generating the output value.

Neuron

A neuron, alternatively called a perceptron, is the fundamental unit of a neural network. It receives an input value and outputs a value depending on that value.

As previously stated, each neuron gets a portion of the input and transmits it to the next layer’s node through the non-linear activation function. TanH, sigmoid, or ReLu activation functions are all possible. The non-linear nature of these functions aids in network training.

Weight space

Each neuron has a unique numerical weight. When it transmits data to another node, its weight is added to that of the other notes to form an output. The training of neural networks is accomplished by making tiny adjustments to these weights. Weight fine-tuning assists in determining the optimal set of weights and biases. This is where the concept of backpropagation comes into play.

What is Backpropagation in a Neural Network Model?

Backpropagation is one of the methods for effectively determining the modest modifications that need to be made to the weights in order to reduce the network’s loss.

Initially, activations should be transmitted upward or in a feedforward fashion.

Now, the derivatives of the cost function must be transmitted downward or in another way.

With this method, you can calculate the partial cost derivative for each weight. You may then calculate the cost savings associated with the modifications.

Why is Backpropagation needed in neural networks?

Errors are propagated backwards in artificial neural networks via backpropagation. In order to train artificial neural networks in an iterative fashion, this method is standardized. A neural network’s weights are fine-tuned through backpropagation, which reduces errors and improves the system’s accuracy and dependability. Using this method is a cinch to implement. You don’t need to know anything about neural networks in order to use this strategy. It does nothing more than fine-tune the figures already given by the system and requires no further configuration.

Conclusion