Hi,
If I understand you correct, you want container items to show up higher, meaning document libraries and lists, and then the names of the list. Same goes with hits in Content Type, metadata and file names.
The first place to start is to look at the default rank profile and the BM25Main part of it as seen at http://msdn.microsoft.com/en-us/library/office/dn169052(v=office.15).aspx#sp15_rank_features
If you look here you see there are seven managed properties listed, each with different weights:
- body
- title
- author
- filename
- qlogclickedtext
- anchortext
- socialtag
It's not particularly easy to see how much they all relate to each other in terms of weight, but Title is given most and body the least.
If you then head over to the schema page for your managed properties and click "advanced settings" on for example title, you will see which "Weight group" it is mapped to. Also listed here: http://technet.microsoft.com/en-us/library/dn169065(v=office.15).aspx#Ranking_Schema
So... you want your tags to improve on relevancy. If you have a site column named MyTaxColumn, then you will have a managed property automatically created for you named owsTaxIdMyTaxColumn. If you go to the advanced settings page for this one and set the
context level to 1, then hits in this field will get the same relevancy as title. For content types, you would change the context level of the managed property SPContentType from 0 to 1,2,5 or 7, in order to give it some more rank points.
Note that a higher context level does not mean higher ranking. This depends entirely of the value the managed property have in the rank profile.
So, by using the same context level as an existing managed property in a rank profile you are getting the same rank weight by association. Think about it a couple of times and let it sink in.
Then after changing context level, do a full crawl of the items affected, and you should see a change in the rank for these items. I recommend using the SharePoint 2013 Query Tool from codeplex or a debug template, in order to see the actual rank score.
You can also create a copy of the default rank profile, and change numbers yourself or add more managed properties to it. But it's not easy.
The other approach is to add boosts to the queries using XRANK. If there's a match in the field, then boost.
Example: {searchTerms} XRANK(cb=1) filename:"{searchTerms}"
In the above query template hits in filename would give 1 extra rank points to the results. The same approach can be applied to any managed property which is queryable, and you can nest the statements.
Hope this helps somewhat... tuning rank is not easy, and you have to check if you want absolute order of results or just nod it upwards or downwards.