pedantic: the urban dictionary example is voting not rating. that's what leads to the confusion of adding up all the positives and negatives.
amazone is rating. it's a scale and there is a clear mean, medium and standard deviation.
whether solution #2 is wrong kind of depends. some of this is a social problem on what items get the kind of followers who are likely to rate online. at the extreme case you could imagine a product where (not) liking it was caused by an inability to use html forms.
amazone is rating. it's a scale and there is a clear mean, medium and standard deviation.
whether solution #2 is wrong kind of depends. some of this is a social problem on what items get the kind of followers who are likely to rate online. at the extreme case you could imagine a product where (not) liking it was caused by an inability to use html forms.