11.2. Hypothesis Test: Multinomial
Population
General Case:
Suppose
there are K populations. We want to test
vs.
![]()
where
![]()
We
also have the following information:
total sample size: ![]()
observed numbers:
.
In
addition, as
is true, the
expected numbers are
expected numbers: ![]()
Chi-Square Test:
The
chi-square test with level of significance
for
vs
![]()
is to
,
where
,
can be obtained by
,
and where
is the random variable
distributed as chi-square distribution with degrees of
In
addition,
.
Example 2:
The
following data are the frequencies of products of throwing a dice 120 times:
|
Point |
1 |
2 |
3 |
4 |
5 |
6 |
|
Frequency |
13 |
24 |
18 |
22 |
19 |
24 |
Please
test if the dice is fair (i.e.,
) with
.
[solution:]
![]()
Then,

Since
,
we do not
reject
.
JavaStatSoft:
Chi-square
test:
Statistics
-> Tests -> Chi-Square Tests -> Hypothesis Test: Multinomial
Population