A lot of this does, in fact, get solved through machine learning. If one search query is conducted a hundred times by different people with otherwise similar pr

A lot of this does, in fact, get solved through machine learning. If one search query is conducted a hundred times by different people with otherwise similar profiles, the machine learning can constantly modify the results until the hundredth person sees the best results first. For example, if the first 25 people all click on the 2nd, 4th, 5th, and 8th result and then stop, it can modify the order of the results for the next 25 people, and randomize the order, so that some see 8-4-2-5 first, and others see 2-5-8-4, etc. The it re-assesses the results and gets smarter. The gaming part is where there's a lot of importance, since it forces the machine to learn which users are acting nefariously.