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Conception

The Perceptron was conceptualized in 1957 by Frank Rosenblatt. By then, scientists had figured that neurons in the brain uses electrical signals to input and output information as well as store information in the neuron. Based off that, on an IBM 704 computer at the Cornell Aeronautical Laboratory, wrote the first Perceptron program, a datastructure that simulates the neuron using inputs and weights.

Perceptron

original perceptron
The first part of the perceptron is the input. The input can be represented as a series of nodes, originally binary inputs ($x_i$) all with their own individual weight ($w_i$). We will then get the sum of all the inputs and weights multiplied, represented by the following equation: $$ \sum^n_{i=0}{x_i \cdot w_i} $$ Now we must determine our threshold value. The threshold will be compared to the results of the previous equation to determine whether the final output will be 1 or 0. This value will be adjusted throughout the training process to determine the best results, but if you are looking for something in the middle, you take the sum of the weights and divide by 2. $$ \frac{\sum^n_{i=0}{w_i}}{2} $$ Now using our threshold, we can determine the Activation Function. The activation function determines whether the the final output of the perceptron, originally a 1 or a 0. It is simply represented as $sum > threshold$.

Example

Let's say you're planning on buying a game, some factors that might help you decide on a certain game could be whether the game has positive reviews, has good graphics, looks fun, is affordable, and is a genre that you enjoy. Below we've simulated this scenario.

Positive Reviews
Good Graphics
Looks Fun
Is Affordable
Liked Genre
Threshold % of total weights