title: Is there any difference between an activation function and a transfer function?
body: <p>It seems there is a bit of confusion between activation and transfer function. From <a href="http://en.wikibooks.org/wiki/Artificial_Neural_Networks/Activation_Functions#Activation_Functions" rel="noreferrer">Wikipedia ANN</a>:</p>
  <p><img src="https://i.stack.imgur.com/ibYr3.png" alt="enter image description here" /></p>
  <p>It seems that the transfer function calculates the net while the activation function the output of the neuron. But on <a href="http://www.mathworks.it/it/help/nnet/ref/satlin.html" rel="noreferrer">Matlab documentation of an activation function</a> I quote:</p>
  <blockquote>
  <p>satlin(N, FP) is a neural <strong>transfer</strong> function. Transfer functions calculate a layer's output from its net input.</p>
  </blockquote>
  <p>So who is right? And can you use the term activation function or transfer function interchangeably?</p>