Training a simple Neural Network in a Spreadsheet

For SOME1, I made a video series that walks the viewer through making a few different neural networks in a spreadsheet.

Why a spreadsheet? I find it easier to reason about how all the steps and equations fit together when you can see them all at once and a spreadsheet is a good mechanism for that.

The functions learned aren't particularly complex: the series covers the AND function, the XOR function, and then a 1 bit half-adder. However, these functions are easy to visualize in 3D (and Bubble charts) and can help explain why hidden layers are necessary.

Part 1 is available now. Part 2, which covers deep neural networks, should be out soon.