[grzm]

See the FAQ (https://news.ycombinator.com/newsfaq.html), in particular:

> How are stories ranked?

> The basic algorithm divides points by a power of the time since a story was submitted. Comments in threads are ranked the same way.

> Other factors affecting rank include user flags, anti-abuse software, software which demotes overheated discussions, account or site weighting, and moderator action."

and

> What does [flagged] mean?

> Users flagged the post as breaking the guidelines or otherwise not belonging on HN.

> Moderators sometimes also add [flagged] (though not usually on submissions), and sometimes turn flags off when they are unfair.

You might also find the guidelines helpful in answering your questions.

https://news.ycombinator.com/newsguidelines.html

[tpoacher]

Thanks gzrm!

So effectively a single normal user can flag a submission. Interesting.

[grzm]

Depends on what you mean by "a single normal user can flag a submission". Any user with sufficient karma (30-odd?) can click "flag". The number of flags a submission has will affect its ranking, and with a sufficient number of flags, the [flagged] tag will appear.

Note that other actions (including voting on the submission, and commenting/participating in the discussion) also affect ranking (according to the FAQ).