[support] How to extend the factors of content ranking?

[Alex]

Hi!

What would be the best way to extend the factors of content ranking in
drupals search by the (numeric) value of a specific field in a content type?

E.g. I have a content type with a field 'rating' which takes values from
1 to 4.
I want to see entities with a rating of 4 on top of the search results
and the
rest in descending order of the field 'rating'.

Thanks in advance,
Alex