If a question has received answers but not been closed within three days, email is sent to the asker reminding him or her to grade. If the question remains open after four such reminders have been sent (over 2 weeks), an attempt is made to select the best answer automatically.
An 'autograding robot' makes its selection based on the net number of peer 'agrees' received by each answer, according to the following rules:
- To be considered, an answer must have at least two "net agrees" (agrees-disagrees).
- The answer with the highest number of net agrees is selected. If two answers have the same number of net agrees, the last one entered is selected. The idea is that if two answers gather the same number of net agrees, the one that did so in a shorter period of time may be better.)
If no answer has at least 2 net agrees, it remains open.
Here is the link: http://www.proz.com/faq/kudoz#kudoz_question_grading
Hope this helps.