The tags are hardcoded, they are keywords I'm interested in. I'm looking for a remote job and there was no way to search for a combination of tags.
You can see the code I used to extract the data here: https://github.com/lsenta/pow/blob/master/who-is-hiring-2015...
If I understand correctly, a post with "remote work currently not possible" statement will be tagged as remote? (not that I have a better idea, just wondering how it works :)
EDIT: postings are a bit difficult to read because of (lack of) newlines. Also, I would prefer Verdana to Helvetica, but that's my personal preference...
As outlied by mattmanser, the standard for non-remote is ONSITE. Which is respected by most of the posters this month.