I'm applying to PhD programs and some require writing samples with a reminder of prioritizing works that are related to the phd program or to my research proposal. The only related writing I have is the paper I'm working on now as a research assistant.
The research topic is my professor's of course, and I'm sure I will not be listed as a co-author. I did write the paper from scratch, but the professor has constantly reviewed its structure and content, and provided comments on things that need to be changed. I did the literature review (research, reading, synthesis, writing), the data collection, statistical analysis, and discussion of results.
I would say that for the current version of the paper, content is 80% mine. Of course, the seed idea was the professor's, but the concept of the paper has changed based on my input after I did the literature review. Would it be okay to submit a portion of this as a writing sample for my phd applications? Or is this not allowed since I'm just a research assistant and not a co-author? Also, the paper is meant to be submitted to a journal for publication so will it be illegal for me to submit a portion of it as a writing sample? I will definitely not send the results sections.