Inferential Statistics and Distributions 13–3
8250FC~1.DOC TI-83 international English Bob Fedorisko Revised: 10/26/05 1:39 PM Printed: 10/27/05 2:57
PM Page 3 of 36
4. Press … | to display the STAT TESTS
menu, and then press † until 8:TInterval is
highlighted.
5. Press Í to select 8:TInterval. The
inferential stat editor for
TInterval is
displayed. If
Data is not selected for Inpt:,
press | Í to select
Data.
Press † and [H] [G] [H] [T] at the List: promp
(alpha-lock is on).
Press † † Ë 99 to enter a 99 percent
confidence level at the
C.Level: prompt.
6. Press † to move the cursor onto Calculate,
and then press Í. The confidence interval
is calculated, and the
TInterval results are
displayed on the home screen.
Interpret the results.
The first line, (159.74,173.94), shows that the 99 percent confidence interval for the
population mean is between about 159.74 cm. and 173.94 cm. This is about a 14.2
cm. spread.
The .99 confidence level indicates that in a very large number of samples, we expect
99 percent of the intervals calculated to contain the population mean. The actual mean
of the population sampled is 165.1 cm. (introduction; page 13.2), which is in the
calculated interval.
The second line gives the mean height of the sample
þ
þþ
þ used to compute this interval.
The third line gives the sample standard deviation
Sx. The bottom line gives the
sample size
n.
To Next Page
Loading...
Need help?
General
