Given a random initialization of w at some value w 1 , and assuming the loss function L happened to have the shape in Fig. 5 .3, we need the algorithm to tell us whether at the next iteration we should move left (making w 2 smaller than w 1 ) or right (making w 2 bigger than w 1 ) to reach the minimum. .3 The first step in iteratively finding the minimum of this loss function, by moving w in the reverse direction from the slope of the function. Since the slope is negative, we need to move w in a positive direction, to the right. Here superscripts are used for learning steps, so w 1 means the initial value of w (which is 0), w 2 at the second step, and so on.