The Machine Learning “Advent Calendar” Day 17: Neural Network Regressor in Excel

A neural network regressor is built from scratch using Microsoft Excel to demystify its "black box" nature. The tutorial explains the core concepts of forward propagation for making predictions and backpropagation for training the model. It details how to use gradient descent to minimize the mean squared error by iteratively updating the network's seven parameters. By making every calculation visible in a spreadsheet, the process shows how the model gradually learns to fit non-linear data.