[Gtex555]

This is a fun post, I got a few ideas.

solutions 1:

Obviously most 1 star and 5 star reviews are not credible so you can just ignore them and get a rating based on the other ratings but the users cannot know that you are ignoring said reviews

solution 2:

Rating system from 0 and 10 as it gives the user more room to describe their experience, it also has the secondary benefit of being something you can normalize. If the average review is a 8/10 , that becomes your new 5/10 and you can devise some kind of mean and standard deviations from the mean system. again you can ignore like 0/10 or 10/10 ratings for the same reasons as previously mentioned.

solution 3:

Could use some combination of sentiment analysis and correlate it to the numerical rating.

Ultimately the user should not know how the sausage is made, much like the youtube algorithm, some things are obvious but its vague enough to make gaming the system harder than a basic 5 star rating of equal weight.