Despite the fact that there is no official driving variable behind an invite or going out or not, every day we are correct to be more pessimistic about being invited. Every time that someone else is invited, it consumes an interview spot, thereby reducing the number of spots by one and the number of people seeking spots by one. If we were to be invited, we would be told so immediately. However, if we were to be rejected, we are not told so until the entire invitation period ends. As a result, odds decline over time. If invitations are issued linearly from the application deadline to one week before notification, our odds would look something like this:
10/3/12
~1000 invitations to be distributed
~7000 applicants
=14% chance of being invited to interview
11/19/12
~254 invitations to be distributed
~6254 applicants yet to be invited
=4% chance of being invited
12/5/12
0 invitations to be distributed
~6000 applicants yet to be invited
=0% chance of being invited