The Hogan is an online personality test that is an initial part of the interview process. When UAL calls you based on your airlineapps profile, the first screening step is to assign you the Hogan test. From what I am told, the failure rate of the Hogan is around 1 in 10. If you successfully complete the Hogan test, the next step is an invitation to the actual interview.

In other words, you do not need to worry about the Hogan as part of your application- it is a screening process for selected applicants.