Machine Learning, Gradient Descent, Hessian Matrix, Optimization, Artificial Intelligence.
x²+y². The graph looks like a bowl (concave up in this case). Image created in Python Saddle Points: Consider f(x, y) = x² — y². The Hessian has a positive eigenvalue in the y-direction and a negative one in the x-direction. This creates the saddle shape. The Hessian and Concavity Yes, but what is