- By analyzing vast amounts of digital data, neural nets can learn all sorts of useful tasks, like identifying photos, recognizing commands spoken into a smartphone, and, as it turns out, responding to Internet search queries. In some cases, they can learn a task so well that they outperform humans. They can do it better. They can do it faster. And they can do it at a much larger scale.This approach is called deep learning.
- In the past, Google relied mostly on algorithms that followed a strict set of rules set by humans. The concern—as described by some former Google employees—was that it was more difficult to understand why neural nets behaved the way it did, and more difficult to tweak their behavior.
- The truth is that even the experts don’t completely understand how neural nets work. But they do work. If you feed enough photos of a platypus into a neural net, it can learn to identify a platypus. If you show it enough computer malware code, it can learn to recognize a virus.
- “it’s hard to explain and ascertain why a particular search result ranks more highly than another result for a given query.” And, he added: “It’s difficult to directly tweak a machine learning-based system to boost the importance of certain signals over others.”
- “People understand the linear algebra behind deep learning. But the models it produces are less human-readable. They’re machine-readable,” Nicholson says. “They can retrieve very accurate results, but we can’t always explain, on an individual basis, what led them to those accurate results.”
- Today, Google is facing an European anti-trust investigation into whether it unfairly demoted the pages of certain competitors. What happens when it’s really the machines making these decisions, and their rationale is indecipherable? Humans will still guide these machines, but not in the same way they were guided in the past.
- RankBrain (the deep learning system) helps Google deal with about 15 percent of its daily queries—the queries the system hasn’t seen in the past. Basically, this machine learning engine is adept at analyzing the words and phrases that make up a search query and deciding what other words and phrases carry much the same meaning. As a result, it’s better than the old rules-based system when handling brand new queries—queries Google Search has never seen before.
- “By building learning systems, we don’t have to write these rules anymore, increasingly, we’re discovering that if we can learn things rather than writing code, we can scale these things much better.”