I agree that that's what happened here, but maybe Google didn't think so, or automatically assumes that the above is typically the scenario where one-star reviews are given.
Such reviews will naturally be at one end of the spectrum or the other - either one star or five stars, so as to maximize your voting power. So they might detect it in the case of reviews being bimodally distributed. I'd expect that two star reviews should always be treated as honest, so I'd recommend that as a review floor to prevent getting accused of manipulation and deleted.
I think reviews are naturally bimodally distributed because people are most likely to take the time to review a business when it is either amazing or horrible.
I would speculate that this is the reason that Yelp created its Elite program — to incentivize people to write tons of reviews, including for places that were neither amazing nor horrible. This gives Yelp the crucial middle ground reviews that as you say are more likely to be accurate than just the highs and lows.
This is why NetFlix switched to thumbs up/down, and the reviews are just as useless as before but more explicit in their useless-ness.
Funny that Steam does this too, but I find their reviews quite useful and accurate. Maybe because you rationalize your review and then give it an overall UP/DOWN, vs all these other approaches that ONLY give you the GO/NO-GO signaling...
Yes, I agree. They are naturally bimodally distributed, but I'd expect Google is arrogant enough to think that they can tell the difference between an honest and manipulative review using such statistics anyway.
They obviously can't, and that's why people are outraged.
Such reviews will naturally be at one end of the spectrum or the other - either one star or five stars, so as to maximize your voting power. So they might detect it in the case of reviews being bimodally distributed. I'd expect that two star reviews should always be treated as honest, so I'd recommend that as a review floor to prevent getting accused of manipulation and deleted.