What's the difference between a good and bad selfie? A neural network artificial intelligence, trained on a diet of over two million selfies, apparently knows. First, the important findings: good selfies involve being a woman -- and one that's tilting their head. A small forehead and longer hair are good points too. Filters help, as do borders. For men, while they didn't rank in the AI's top 100 (ugh, bias!), the bot advises that you show your full head and shoulders. Longer hairstyles (and ones combed upwards) don't hurt mens' chances either. Its creator, Andrej Karpathy, who has worked with Google Research and DeepMind, explains that it's a convoluted neural network which does the image recognizing and, er, judging. You can judge yourself (for yourself) using the network's Twitter bot (61.7 percent here), or read on for how it learned to do all that.