Chi square: evaluation
•
If H
0
of no association is
true
, then f
o
and f
e
will be close and the chi square
value small
•
If H
0
of no association is
false
, f
o
and f
e
should be relatively farther apart, and
hence the chi square value larger
•
Chi square value = 0 when f
o
= f
e