Require Physical Validation

Review bombing, and review boosting are situations where a user leaves feedback on an online entity without consuming the service or product that the review is for. In many instances, this could be dramatically ameliorated if users were required to provide some level of physical validation of their consumption of the service. For example, for restaurant reviews, a user might have to have a location history indicating that they were proximate to the restaurant. For product reviews the user might have to attach a photo of the entity that they are reviewing. This additional data would make for easy fodder for good content-analysis tools: restaurants with lots of reviews non-proximate to it, or products with lots of reviews of things that have minimal or no similarity would be more easily flagged as likely inauthentic.

This approach has significant downsides, however, in that the privacy tradeoffs are stark, and would make implementing a system like this in certain contexts (like rating medical professionals) untenable. Though it cannot be used in every feedback aggregation context, this approach can and should be considered in some.