Stack Exchange network consists of 183 Q&A communities including Stack Overflow, the largest, most trusted online community for developers to learn, share their knowledge, and build their careers.
At the beginning I was like yeah this is right! I need the squared error. But then I figured out that I am actually using mean-squared-error. The error that is using in back-propagation is the derivative of the cost function, right? I am printing the error like (Σ(expected_error - actual_error)²)/n. So the error that I need to back propagate is the derivative of the cost function which is the function that I am using to find the average. This one (expected_error - actual_error)² which derivative is actually the one that I wrote to my question 2.0 * (expected_output - actual_output)right?