Casio fx9750GII Getting Started page 71

Confidence Intervals [in STAT]
There are four types of confidence interval calculations, one statistic (1-S), two statistic (2-S), one proportion (1-P), and
2 proportions (2-P).
KEY
RESULT
KEY
RESULT
Confidence Intervals 1-S type
Example
Consider the following collected statistics. A
sample was taken of worm lengths at different
areas of a market garden. Test at the 95%
confidence level, to see if there is a statistical
difference between the worm lengths of this
sample and the 'true' population mean.
Set the calculator up so that inputted statistics is being used, not 'raw data'. As
you can see raw data can be using in the LIST columns.
F4 F1
Z-score
0 .
. 4 EXE
This gives the interval [9.7976, 11.002], hence the 'true' population mean for the
worm lengths is in this interval, at the 95% confidence level.
Confidence Intervals 2-S type
Example
Consider the following collected statistics. Two samples were taken of worm
lengths at different areas of a market garden. Test at the 90% confidence
level, to see if there is a statistical difference between the worm lengths of two
samples.
Standard deviation = 1.2
F1 F2
[1-S] [VAR]
9 5 EXE 2
5 6 EXE then EXE
Sample 1
n = 45
Mean = 5.4
Standard deviation = 1.15
Note:
You will have a choice of 4 different options of
confidence intervals. 1-S, 2-S, 1-P, and 2-P. Use the
function to select the one that fits with the statistics.
Sample
n = 56
Mean = 10.4
Standard deviation = 2.3
. 3 EXE 1 0
Sample 2
n = 80
Mean = 5.3
fx9750GII
Result
C-Level is at the
95% level
[9.7976, 11.002]
Result
cont. on next page
CHAPTER 8 | PG 71