qualifier number + unit a measured amount
review rating
The score a single review assigns the product, as a numeral on a rating unit (4 stars; 8 points). A qualifier of the review property — each review statement carries its own rating. The rating SCALE (out of how many) is the aggregate-rating host's concern, not repeated here; the per-review value is read against the same unit.
Review rating is a measured figure.
It is a qualifier of review — it has meaning only inside a review statement, one per statement, never on its own. It belongs with review to social proof — what buyers and critics say about it.
It is answered inside every review statement, not as a standalone question on a kind.
Answered inside every review statement — not a standalone slot on any kind.