Survey and all the information you need to know is on this page.
More information on the people hosting this survey can be found from this article which was posted here a few days ago. The important part is that they are scientists and are performing this without bias.
I am in no way connected to people running the survey. I am just someone interested in science and having psychologists better understand the mentality of fellow bronies.
I do not receive any karma from this post, so please upvote so we can get more people to participate!