Texas Instruments 83PL/CLM/1L1/V - 83 Plus Calc, Руководство пользователя

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TI-83 Plus Inferential Statistics and Distributions 384
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 centimeters
and 173.94 centimeters. This is about a 14.2 centimeters 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
centimeters, which is in the calculated interval.
The second line gives the mean height of the sample
þ
used to compute
this interval. The third line gives the sample standard deviation
Sx
. The
bottom line gives the sample size
n
.
To obtain a more precise bound on the population mean
m
of women’s
heights, increase the sample size to 90. Use a sample mean
þ
of 163.8
and sample standard deviation
Sx
of 7.1 calculated from the larger
random sample. This time, use the
Stats
(summary statistics) input
option.
7. Press
… |
8
to display the inferential stat
editor for
TInterval
.
Press
~ Í
to select
Inpt:Stats
. The editor
changes so that you can enter summary
statistics as input.