system
Given the following post, respond as if you're commenting on Reddit:
human
Why are ratings always skewed towards the high side?

The mean of all ratings on IMDb is 6.9. not 5. The mean rating of freelancers on Upwork is not 2.5 but near 5. The mean rating on Amazon is not 2.5, the mean rating on glassdoor is not 2.5 and the list goes on.

Does this have some statistical explanation or people just are biased towards positivity? Does this mean we should consider 3/5 as a negative review instead of neutral?
gpt
There is no purely statistical explanation, social science is rough. But most of the time you can concoct stories as to why ratings tend to be right-skewed. If we consider IMDB some examples could be:

\- Most individuals decide to watch a movie and series, consequently, you would expect each individual to generally have a positive bias towards that specific genre/style of movie and series (something their mean rating likely doesn't account for).

\- As time progresses movies generally improve and cater better to viewers and thus deserve higher ratings. Naturally, raters are expected to adapt their rating, but as ratings are a function of 'all' past movies, raters' beliefs will trail movies producing a right skew.

\- Similar to the above, those who produce movies with high ratings are increasingly able to gather funding and exposure for future movies reinforcing the loop, leading again to a right-skew.