Casio FX-CG10 - Manual (Page 262)

6-69
k Confidence Interval
Confidence Interval
Lower : confidence interval lower limit
Upper : confidence interval upper limit
1-Sample Z Interval
Lower, Upper =
o
+ Z ( /2) · σ /
' n
α
2-Sample Z Interval
Lower, Upper = ( o
1
– o
2
) + Z ( /2) σ / n
1
+ σ / n
2
2
1 2
2
α
1-Prop Z Interval Lower, Upper = x / n + Z ( /2) 1/ n · ( x / n · (1 – x / n ))
α
2-Prop Z Interval
Lower, Upper = ( x
1
/ n
1
– x
2
/ n
2
)
+ Z ( /2) ( x
1
/ n
1
· (1 – x
1
/ n
1
))/ n
1
+ ( x
2
/ n
2
· (1 – x
2
/ n
2
))/ n
2
α
1-Sample t Interval
Lower, Upper = o + t
n −1
( /2) · s
x
/
' n
α
2-Sample t Interval
(pooled)
Lower, Upper = ( o
1
– o
2
) + t
n
1 + n
2 −2
( /2) s
p
2 (1/ n
1
+ 1/ n
2
)
s
p
= (( n
1
– 1)s
x 1
2 + ( n
2
– 1)s
x 2
2 )/( n
1
+ n
2
– 2)
α
2-Sample t Interval
(not pooled)
Lower, Upper = ( o
1
– o
2
) + t
df
(
/2) s
x 1
2 / n
1
+ s
x 2
2 / n
2
df = 1/(C 2 /( n
1
– 1) + (1 – C) 2 /( n
2
– 1))
α
C = (s
x 1
2 / n
1
)/(s
x 1
2 / n
1
+ s
x 2
2 / n
2
)
α : level of significance α = 1 − [C-Level ] C-Level : confidence level (0 C-Level < 1)
Z (
α /2): upper α /2 point of standard normal distribution
t
df
(
α /2): upper α /2 point of t distribution with df degrees of freedom