Thread:Sunou-san/@comment-25787298-20170408140723/@comment-27247962-20170424224221

In regards to the starting topic,  very simple, a form of research.

It's exact explanation besides the starting topic. A form of study that tries to perceive trends in a certain aspect of people through repeated observations of that variable over a long period of time. Roughly, there's more to it, as with most things.