Kathy Sierra, author of the Creating Passionate Users blog at headrush.typepad.com displays this provocative Figure © 2007:
![]() |
Kathy explains that, while we need predictability, we also benefit from some degree of randomness in our lives. This Figure has obvious implications for classroom management and curriculum development. Encourage an element of surprise within a stable environment.
This concept exactly matches Rasch fit statistics. Let us revise Kathy’s Figure:
![]() |
The essential idea behind putting many items on a test is that we learn something new from each response. That new component must neither monotonously repeat nor seriously contradict what we already know about the person and the item who interacted to generate the response.
Rasch Fit and Serendipity, Linacre J.M. Rasch Measurement Transactions, 2007, 20:4 p. 1086
The URL of this page is www.rasch.org/rmt/rmt204e.htm
Website: www.rasch.org/rmt/contents.htm