Casio ALGEBRA FX2.0 Advanced Statistics Examples 2 - Manual (Page 14)

39
examples
○ ○ ○ ○ ○
Example Factory A and Factory B both manufacture the same item. To compare
the productivity of the two factories, the production data shown below
was collected for 10 items at Factory A and nine items at Factory B.
Factory A: 78, 80, 79, 83, 82, 85, 78, 74, 76, 84 (kg/h)
Factory B: 81, 84, 82, 88, 86, 83, 78, 84, 89 (kg/h)
Construct a 95% confidence interval for the difference between
µ
1
and
µ
2
when the following is assumed:
σ
1
2 =
σ
2
2 is uncertain, Factory A
population distribution is N(
µ
1
,
σ
1
2 ), and Factory B population
distribution is N(
µ
2
,
σ
2
2 ).
Procedure
1 m STAT2
2 hi wiawhjwidwicw
if whiwhewhgwiew
e
ib
wiewicwiiwigw
id whiwiewijw
3 4 (INTR) c (T) c (2-Smpl)
4 1 (LIST) c
.jf w
1 (LIST) b wc
1 (LIST) c wc
1 (1) c
1 (1) c
2 (Off) c
1 (None) c
4 1 (CALC)
Result Screen
Thus, the 95% confidence interval for
µ
1
-
µ
2
becomes -7.4<
µ
1
-
µ
2
<-0.6 .