I have been contemplating the relationship between random projections and compressive sensing since reading it and curious to read this paper for any insights on compressive sensing.
This one happens to have "Workshop track - ICLR 2018" at the top so has some dating, but most don't even have that
Papers without a date are usually preprints, or published independently (e.g. on the author's website) while expecting actual publication at some point.
I think "published" should be "submitted" there. (I suppose that one could argue for regarding submission to the arXiv as publication, especially given the presence of overlay journals—but probably that's not what you meant.)