Backpropagation, Neural Networks.
transpose, we transpose of this. It is just going to be, n¹ by n²-dimensional, dz² is going to be n² by one-dimensional. Then, this is same dimension as z^. This is also, n¹ by one-dimensional, so element-wise product. The dimensions do make sense. N¹ by one-dimensional vector can be obtained by n¹