Three years after it last released Gmail’s spam stats, Google says that its spam rate is down to 0.1 percent, and its false positive rate has dipped to 0.05 percent. The company credits the significant drop in large part to the introduction of brain-like “neural networks” into its spam filters that can learn to recognize junk mail and phishing messages by analyzing scads off the stuff across an enormous collection of computers.
“One of the great things about machine learning is that it adapts to changing situations.” says John Rae-Grant, a senior product manager for Gmail, which Google says is now used by 900 million people across the globe. In other words, Gmail’s spam filters don’t just curb junk by applying pre-existing rules. They create new rules themselves as they go along.