People do best at classifying things into sets if the number of sets is small. Therefore, a Five Point Scale is generally the easiest to use, both for classification and understanding.
See:
http://www.well.com/user/smalin/miller.html "The Magical Number Seven, Plus or Minus Two"
Sat, 29 Nov 2003 17:42:03 GMT | Front Page | Recent Changes | Message Of The Day |