I’ve noticed a number of researchers on RG posting “certificates of attendance” as a research item. I must confess I have not come across such a practice before. I know that attendance at a certain number of talks or presentations is a requirement for students in some graduate programs, so I can see the point of a certificate of attendance as proof that the requirement is being satisfied. I can also see the point of such a proof of attendance for those who aren’t on the conference program but are nevertheless getting their expenses paid by others. What further purposes do such certificates serve?