Is it ethical to use a data-set made as a research assistant? Two years ago I was a research assistant during my undergraduate and my sole duty was the aggregation of many economic surveys, a very tedious task. This data-set, to my knowledge is one of a kind. 

Now in graduate school, I had come up with a research idea, and this data-set that I made would be perfect for my research. My research idea is not related to my previous professors, though as of yet, he has no present publication for the research he was doing when I was working for him. 

My question is, would it be ethical for me to use this data-set for my own research when I had made it while being employed for my previous professor. The obvious response would be to ask him but sadly we had a falling-out just before I graduated.
As with any situation, there are many levels to any answer… Mainly, the question is: was the data-set published? If so, who owns the copyright? Probably not your professor, but the university. If it wasn't published, then it isn't ethical to use the records you kept of it for another purpose, without authorization from your employer.

However, there might be a solution, regardless of your fall-out before graduation. [1] Just get your current advisor to ask him! One staff researcher to another, the situation is not the same as you dealing with your formed professor.



[1] I am amazed at how many times I have read this situation (I cannot speak to my adviser/professor/…) raised in questions on this site! Every time, I think: before or around the time of graduation, aren't you a bit young to make “enemies”? I can sure name many people I thought fools or who annoyed me during my studies and early career, but I always tried as hard as I could to get things done in a manner that no bridge was burnt…