I see different estimation ranges for the following estimations.

Estimation Range              in PMBOK     Rita                 www.scribd.com 101 Qs

Rough Order Magnitude    +/- 50%        +/- 50%           -25% to +75%
Definitive estimate             +/-10%         +/-10%             -5% to 10%
 

Which one to follow? Do we follow PMBOK?

Also, how to copy contents from word doc to this fourm? Whenever I click the word icon here - the forums hanges; I need to kill that session and restart it.

Thanks

Jai