RatingType will display a star rating system when applied to a numeric column. The star-rating is rounded up (0, 0.5, 1...) but you can see the actual average rating by hovering over the stars (e.g. 4.36).
Note: The star rating system uses 0 as a minimum and 5 as the maximum.
If your data does not use the 0 - 5 rating system, they will automatically be forced to use that setup (i.e. negative numbers are converted to 0, and numeric values greater than 5 are converted to 5)