Good question, avoiding bias of any sort when looking at results is always a problem.
The cup story is actually a bit different than in the article. I don't bring in a cup, it is the interviewee's own cup or bottle of water. So what I observed over time that some people never felt like it was their responsibility to clean up after themselves, a question of simple manners more than a trick/test I am putting them through.
Wow, that little detail changes everything about the article. They should edit it to be correct.
I'm the kind of person that would pick up my own cup, but if it was the interviewer's cup, I definitely wouldn't pick it up. I'd also probably have a slightly negative impression of the interviewer for not doing so.
The cup story is actually a bit different than in the article. I don't bring in a cup, it is the interviewee's own cup or bottle of water. So what I observed over time that some people never felt like it was their responsibility to clean up after themselves, a question of simple manners more than a trick/test I am putting them through.